Final Report of the investigation into the probable causes of the

FINAL REPOR

Final report of the investigation into the probabl

causes of the accident with the KLM

Cityhopper

fligh

KL433, Saab 340B, PH-KSH at

Schiphol,

Amsterdam Airpor

on 4 April 1994, conducted by the Netherlands Aviatio

Safety Board, composed of

. Bodewes, Chairman

Snoek,

Membe

Hofstra, Membe

Barendregt,

Membe

. Corssmit, Membe

Smit,

Deputy Membe

Boyer, Secretar

Hoofddorp, October 1995

CONTENT

LIST OF ABBREVIATION

GENERAL

INFORMATION OF THE ACCIDENT AND THE INVESTIGATIO

THE INVESTIGATIO

SYNOPSI

1 FACTUAL INFORMATIO



History of the Fligh



Injuries to Person



Damage to Aircraf



Other Damag



Personnel Informatio



Captai

.5 .1 .1



Genera

.5 .1



Duty and Rest Period

.5 .1



Medical Histor



First Office



Genera



Duty and Rest Period

.2 .3



Medical Histor



Aircraft Informatio



Genera

.6.2



Engine

.6.3



Propeller

.6.4



Engine and Propeller Histor

.6.5



Weight and Balanc

.6.6



Flighthandling and Performance aspect



Meteorological Informatio



Aids to Navigatio



Communications and Recording

.9 .1



Air Traffic Contro



Ground Operation

.10



Airport

Informatio

.11



Flight Recorder

.12



Wreckage and Impact

Informatio

.12 .1



Accident Site Descriptio

.12 .2



Aircraft Wreckage Descriptio

.12



Technical Examination of the Wreckag

.12



Genera

.12

.2 Flight Control

.12

.3 Engines and Propeller

.12

.4 Engine Instrument

.12 .3

.5 Flight Instruments

.13



Medical and Pathological Informatio

.13



The Crew

.13



The Passenger

.14



Fir

.15



Survival Aspect

.15



Seating Pla

.15 .2



Interior Damage and Survivabilit

.15 .2

.1 Genera

.15 .2

.2 Cockpi

.15 .2

.3 Galle

.15 .2

.4 Cabi

.15

.5 Exit

.16



Tests and Researc

.16



Procedure

.16 .2



Pilot Selection and Trainin

.16 .2

.1 Main requirements pursuant to Netherlands Aviation La

.16

.2 KLC Initial Requirement

.16

.3 KLC Selectio

.16 .2

.4 KLC Type Qualificatio

.16 .2

.5 KLC Captain's Training/Qualificatio

.16

.6 RLD Inspection of KL

.16 .2

.7 KLC's Assessment Procedure of Proficiency Check

.16

.8 Training/Qualification Captain of Flight KL43

.17



Organizational and Management Informatio

.18



Additional Informatio

.19



Useful or Effective Investigation Technique

2 ANALYSI



Oil Pressure Warnin



Technical Aspect

2.1.2



Flightcrew Handling of Oil Pressure Warnin

2.2



Decision Making Proces

2.2.1



Genera

2.2.2



Decision to Return to Amsterdam Airpor

2.2



Decision to Maintain Flight Idle on the

Engin

2.2.4



Choice of Runway 0

2.3



Aircraft Handlin

2.3.1



Descen

2.3.2



Final Approac

2.3.3



Go Aroun

2.4



Crew Resource Managemen

2.5



KLC Pilot Selection and Trainin

2.6



Single Engine Performance SAAB 340

2.7



Procedure

2.7.1



Engine & Prop Oil Pressure Low Procedure

2.7.2



Ruddertrim Procedur

2.7.3



Approach Speeds



Flight Safet

.8 .1



Cabin/Passengers Preparatio

2.8.2



Survivabilit

2.9



Air Traffic Contro

2.10



Fire Fighting & Rescue Service

3 CONCLUSION

4 PROBABLE CAUSE

5 RECOMMENDATION

APPENDIXE

Photograph

UFDR Plots

LIST OF ABBREVIATIONS

AEO



All Engines Operativ

AMS



Amsterdam Schiphol

Airpor

AOM



Aircraft Operations Manua



Auto Pilo

APR



Automatic Power Reserv

ATC



Air Traffic Contro

ATIS



Automatic Terminal Information Servic

ATPL



Airline Transport Pilot's Licenc



ATPL (Netherlands Airline Transport Pilot's Licence

)



SCPL (Netherlands Senior Commercial Pilot's Licence

)



CPL (Netherlands Commercial Pilot's Licence

)

BHX



Birmingham Airpor

BRE



Bremen Airpor

BRU



Brussel Airpor

BVOI



Bureau

Vooronderzoek Ongevallen

Incidente

(Accident en Incident Investigation Bureau

)



Celciu



Cabin Attendan

CHU



Commuter Handling Uni

CMC



Cockpit Management Cours

CPL



Commercial Pilot's Licenc

CRM



Cockpit Resource Managemen

CTOT



Constant Torque On Take of



Cumulu

CVR



Cockpit Voice Recorde

CWL



Cardiff Airpor

CWP



Central Warning Pane

ECL



Emergency Checklis

EGFF



Cardiff Airpor

EGGD



Bristol Airpor

EGHI



Southampton Airpor

EGLL



London Heathrow Airpor

EHAM



Amsterdam

Schiphol

Airpor

FAR



Federal Aviation Regulations (of the FAA

)

FDAU



Flight Data Acquisition Uni



First Office



Flight Leve

FST BV



Flight Simulator Training



Fee

fpm



Feet per minut

GMT



Greenwich Mean Time

HPa



Hectopascal

IAS



Indicated Airspee

IATA



International Air Transport Associatio

ICAO



International Civil Aviation Organizatio



Instrument Flyin

IFR



Instrument Flight Rule

ILS



Instrument Landing Syste



Instrument Ratin

JAR



Joint Airworthiness Regulation



Kilogram(s

)

KLC



KLM Cityhoppe

KLM



Koninklijke Luchtvaart Maatschappij

(Royal Dutch Airlines

)



Kilometer(s

)



Knot(s

)

Lat



Latitud



Pound(s

)



Left Han

Long



Longitud

LUX



Luxembourg Airpor



Meter(s

)

MHz



Megahert

MLH



Basel Mulhouse Airpor

MMX



Malmö

Airpor

MTOW



Maximum Take Off Weigh



Nort

NLRGC



Stichting Nationaal Lucht-

Ruimtevaart Geneeskundig Centru

(Netherlands Aerospace Medical Centre

)

NLM



Nederlandse Luchtvaart Maatschappi



Nautical mile

NOTAM



Notice to Airme

NTSB



National Transportation Safety Board (USA

)

NVLS



Luchthaven Schiphol (Schiphol

Airport

)

OEI



One Engine Inoperativ



Outer Marke

PAN-call



Urgency cal

PAS



Public Address Syste



Pilot Flyin

PIC



Pilot in Comman

PNF



Pilot Not Flyin

psi



Pounds per square inch

PSU



Passenger Service Uni

QNH



Sea Level Atmosphere Pressur



Radio Altitud



Route Da

RLD



Rijksluchtvaartdiens

(Civil Aviation Authority of the Netherlands

)



Right Han

RIV



Rapid Intervention Vehicl

RPM



Revolutions per Minut



Radio Telephon

RTB



Reserve Thuis Beschikbaar

(Reserve/available

)

RTL



Reserve

Thuis [oproepbaar]

(Reserve/on call

)



Reis

Verlof

(Off Duty

)



Stratocumulu

SCPL



Senior Commercial Pilot's Licenc

SOU



Southampton Airpor

SXB



Strassbourg Airpor

UFDR



Universal Flight Data Recorde

UHF



Ultra High Frequenc

UTC



Coordinated Universal Tim



Airspee

VHF



Very High Frequenc

VMC



Visual Meteorological Condition

VSI



Vertical Speed Indicato

VT 1



Summer Type Recurren



Threshold Spee



West

GENERAL INFORMATION OF THE ACCIDENT AND '1'HL INVESTIGATIO

Place

Just outside

Schiphol Airport, on agricultural terrai

adjacent to runway 06, at position

Latitude

N 52°17'27

Longitude

W 004°45'16

Date and time



4 April 1994, 12

:46 UT

Aircraft

PH-KSH, SAAB 340B

The aircraft sustained severe damage during the accident

Crew

2 pilots, 1 cabin attendan

Passengers

Type of flight

Scheduled flight

; IFR/VMC dayligh

•

Type of accident Loss of control during go around

All times in this report are Coordinated Universal Time (UTC) unless otherwis

indicated

. Local time at the place of the accident was Central European Daylight Savin

time, which is UTC+2

THE INVESTIGATIO

The investigation of the accident was performed by the Accident and Inciden

Investigation Bureau of the Netherlands Aviation Safety Board, in accordance with th

Netherlands Air Accidents Law

SYNOPSI

After take off from runway 24, the aircraft followed a VALKO departure as cleared b

Air Traffic Control (ATC)

. During climb, passing flight level 165 (FL165), the Maste

Warning was triggered by the right engine oil pressure Central Warning Panel (CWP

)

light

. The Captain slowly retarded the right hand power lever to flight idle and called fo

the emergency checklist

After completion of the emergency checklist procedure, the right hand engine oil pressur

CWP light was still on and the Captain decided to return to Amsterdam

. The right han

engine remained in flight idle during the remainder of the flight

While returning to Amsterdam, the flight was radar vectored by ATC for an Instrumen

Landing System

(ILS)

approach on runway 06

. After passing approximately 200 fee

height, the aircraft became displaced to the right of the runway and a go around wa

initiated

. During the go around, control of the aircraft was lost and, at 12

:46 UTC, th

aircraft hit the ground, in a slight noselow attitude with approximately 80° bank to th

right, approximately 560 meters right from the runway 06 centerline, just outside th

airport

. Two passengers and the Captain died in the accident; eight passengers and th

First Officer (FO) were seriously injured

An investigation was initiated by the Netherlands Aviation Safety Board

. Following th

procedures contained in International Civil Aviation Organization (ICAO) Annex 13

Accredited Representatives and their Advisors from Sweden and the United States o

America joined the investigation

The investigation team was assisted by specialists from the Aeronautical Inspectio

Directorate of the Department of Civil Aviation of the Netherlands, the aircraft manufac-

turer Saab Aircraft Company, the engine manufacturer General Electric, the propelle

manufacturer Dowty Aerospace Propellers, the operator

KLM

Cityhopper

and

Royal Dutch Airlines

A copy of the Universal Flight Data Recorder (UFDR) tape was handed over to th

United States National Transportation Safety Board (NTSB, USA) to make a data extracti-

on independent from the results of the data extraction in The Netherlands

The Air Branch of the Netherlands State Police assisted with the questioning of witnesses

Following the procedure of ICAO Annex 13, the draft final

report was presented to th

Accredited Representative of Sweden and of the United States of America on 3 Augus

1995 for comments

The Accredited Representative of the United States of America replied on 8 August 199

stating that there were no comments ; the Accredited Representative of Sweden replied o

19 September 1995 stating that there were no comments

Hoofddorp,

3 October 1995

1 FACTUAL INFORMATIO

History of the Fligh

Genera

KLM

flight KL433 was a scheduled daily flight from Amsterdam

"Schiphol"

Airpor

(EHAM) to Cardiff Airport (EGFF), operated by

KLM

Cityhopper

with a SAAB

340B

The crew consisted of two pilots and one cabin attendant (CA)

. The crew reported fo

duty on the 4th of April 1994 at 06

:35 to operate flight KL439 to Southampton (EGHI

)

and subsequently, after their return flight to Amsterdam, flight KL433, from Amsterda

to Cardiff, with the same aircraft

. The flights to and from Southampton were uneventfu

and the aircraft returned to Amsterdam at 10

:55, after which the crew had 1

:15 hour t

prepare for flight KL433

In the previous three months the Captain had made 7 flights to Cardiff, the F0 4 flights

Flight Preparatio

The flight plan, weather and Notice to Airmen (NOTAM) information did not contain an

information that would have required special attention

. Planned flight time from Amster

dam to EGFF was 1 :18 hour and flight plan fuel was 1,830 kg with Bristol Airpor

(EGGD) as alternate airport

. The aircraft was to carry 22 passengers plus 3 crew

At boarding time three passengers did not show up, but later two of these three passen-

gers were transported to the aircraft by bus . The aircraft left Amsterdam with 2

passengers plus 3 crew and 20 pieces of baggage

There were no dangerous goods or International Air Transport Association

(IATA )

restricted articles on board the aircraft

. The take off weight was calculated by th

flightcrew to be 12,589 kg (27,754 lbs)

KLM

Cityhopper

applies a fixed seat policy whereby the Captain occupies the left han

(LH)

seat and the F0 occupies the right hand

(RH)

seat

. On this stretch the Captain wa

the Pilot Flying (PF)

and the F0 the Pilot Not Flying (PNF)

Tax

At time 12

:11

:12, KL433 contacted

Schiphol

Clearance Delivery and requested start up

stating that they had received Automatic Terminal Information Service (ATIS) informatio

"November"

. Delivery approved start up and indicated that runway 24 would be the tak

off runway, after which the airway clearance was given

At 12

:15

:18 taxi was approved by

Schiphol

Ground to exit 2 of runway 06, which is th

2,300 meters intersection of runway 24

. The UFDR automatically started to record fligh

data at 12

:13

:53

. Information recorded on the Cockpit Voice Recorder (CVR) starte

automatically at 12

:15 :21

KL433 was the second SAAB in a sequence of five aircraft to depart Amsterdam fro

runway 24

. Runway OIL was also used as (secondary) take off runway, while runwa

O1R was the main landing runway

The "Taxi-Out" checklist was completed, and approaching the 2,300 meters intersectio

of runway 24, KL433 was instructed by

Schiphol

Ground to contact

Schiphol

Tower

At 12 :17

:57

Schiphol

Tower instructed KL433 to line up in sequence behind the prece-

ding Saab

. The "Before Take Off" checklist was completed at 12

:18

:56 and at tim

:19

:38 KL433 was cleared for take off

Take Of

Passing 1,950 feet height KL433 contacted

Schiphol

Departure and was cleared to clim

to FL090. The Captain commanded for the "After Take Off" checklist at 12

:22 :17

. A

:24

:15 KL433 was instructed by

Schiphol

Departure to contact Amsterdam Radar

Clim

Amsterdam Radar cleared KL433 to climb to FL140

. An active trough, with cumulonim

bus clouds with tops up to FL150, was situated over the southern part of the North Sea

To remain clear of the clouds KL433 contacted Amsterdam Radar and requested FL20

for cruising level instead of FL180 as indicated on the filed flight plan, which wa

approved

Amsterdam Radar instructed KL433 at 12

:28

:41 to turn to the right to fly heading 270, i

order to maintain separation with a Boeing 737

Oil Pressure Warnin

During climb at 12

:30

:46, while passing FL165, the Master Warning was triggered b

the right engine oil pressure CWP light

. The Master Warning was reset

. The Captai

retarded the

power lever slowly to flight idle and commanded "Take action"

. The

engine torque decreased from 78% to 10%

. The F0 confirmed the command "Tak

action" and announced "Emergency checklist"

The right engine oil pressure CWP light indicates a possible low oil pressure in the right engine and/o

in the

right propeller gear

box

. The

procedure

in the

Emergency Checklist (ECL)

for an engine oi

pressure low warning is therefore a combined procedure

. The first item in the procedure is to read the oi

pressure indicators

. Any follow-up action depends on these readings

At 12

:31

:29 the Master Warning was triggered again and after the warning was reset, th

F0 indicated that the oil pressure of the

engine was lower than the oil pressure of th

engine and also that the oil pressure of the

engine was decreasing

[Note

: at

tha

time the Captain was still retarding the

power lever

]

At 12

:31

:35 the Master Warning was triggered for a third time and, after it was rese

again, the F0 stated to the Captain that the oil pressure of the right engine was indee

decreasing

. This was confirmed by the Captain and the F0 then concluded - following th

ECL procedure - that the Propeller Oil Pressure Low procedure was not applicable and h

continued with the Engine Oil Pressure Low procedure

At 12

:31

:43 the F0 proceeded with reading the ECL

: "

.engine oil pressure contro

warning panel light on

. .

. or, engine oil pressure below thirty psi"

. The Captain responde

with

: "That is not the case, but it is still normally in the green, that is what is s

strange", which was confirmed by the F0

. There were no indications on the CVR that th

Engine Oil Pressure Low procedure was completed

. The right engine oil pressure CW

light remained on and the captain left the

power lever at the flight idle position

where it would stay for the remainder of the flight

By then, the Boeing 737 had passed KL433 and Amsterdam Radar cleared KL433 t

proceed direct to position REFSO over the southern part of the North Sea

. The F

confirmed this clearance at 12

:32

:08, but at the same time the

Captain indicated to th

F0, that he would not continue to his destination with an "engine oil pressure low

warning

. The F0 indicated to the Captain that according to the ECL procedure, it shoul

be determined whether or not the engine oil pressure was below 30 psi with the oi

pressure warning light on

According to the ECL procedure the engine must be shut down if the oil pressure warning light is on an

the oil pressure is below

30 psi

. If

the warning

light is

on and the engine oil pressure is above 30 psi

normal operation should be continue

At 12

:32

:37 the Captain stated, that the

engine oil pressure was above 50 psi an

after confirmation of this fact by the F0, the Captain announced

: "Continue norma

operation"

. At 12

:32

:54 the Captain again told the F0, that he did not want to continu

the flight to its destination and thereafter back to Amsterdam

. The F0 agreed

. Neither th

captain nor the F0 expressed a reason for their decision

The Captain then remarked, that the climb performance of the aircraft was considerabl

reduced

. The Captain instructed the F0 to obtain clearance to descend to FL160 and t

inform ATC that KL433 possibly had to return to Amsterdam due to a technical problem

The F0 suggested to the Captain to send out a PAN-call and after some consideration th

Captain agreed that a PAN-call would be appropriate

At 12

:33

:26, KL433 contacted Amsterdam Radar starting the message with a PAN-call

informing them that they had an engine problem and that they liked to maintain FL16

for a return to Amsterdam

Amsterdam Radar confirmed the PAN-call of KL433 at 12

:33

:35 and cleared KL433

turn right, heading to

Schiphol

KL433 responded that they were turning right and tha

they were descending to FL160

At 12

:34

:39 the F0 contacted the Commuter Handling Unit (CHU) at Amsterdam on th

company frequ°ncy and informed CHU that KL433 was returning to Amsterdam with

technical

problem

with

the

engine

. The nature of the problem was

not

indicated

message was confirmed by CHU at 12

:34 :42

After having informed

Schiphol

Approach that KL433 was returning to Amsterdam wit

an engine problem, Amsterdam Radar cleared KL433 to descend to FL070 at 12

:34

and instructed KL433 to contact

Schiphol

Approach

Descen

While the Captain started the descent to FL070, the F0 suggested to the Captain t

inform the passengers

. The Captain decided, that the CA had to be informed first, afte

which the passengers could be informed

. At the suggestion of the F0, the Captai

decided that the F0 was to inform both the CA and the passengers, while he woul

handle the aircraft

At 12

:35

:12 the F0 informed the CA and the passengers that the aircraft was returning t

Amsterdam and that the aircraft would land in approximately 20 minutes

In the meantime

Schiphol

Approach had informed

Schiphol

Tower, that KL433 wa

returning to Amsterdam and consequently

Schiphol

Tower had informed the

Schipho

Airport (NVLS) duty manager . The NVLS duty manager indicated that he would liste

out on the

Schiphol

Approach frequency to follow flight KL433

At 12 :36

:32 the Captain, who was handling the radio while the F0 was informing th

passengers, contacted

Schiphol

Approach starting with

PAN-call

Schiphol Approac

responded by offering KL433 a straight-in approach for either runway 06 or runway O1

and the Captain indicated, that he would use runway 06

Schiphol

Approach confirme

the choice of runway 06, cleared KL433 to descend to 2,000 feet on QNH 993 HPa an

instructed KL433 to fly heading 090

. At 12

:36

:52

Schiphol

Approach informed

Schipho

Tower that KL433 was returning for runway 06 as an emergency and requested to stop al

traffic

After the F0 had finished his statement on the public address system (PAS),

reporte

back to the Captain and was informed that the aircraft was cleared to descend to 2,00

feet on QNH 993 HPa for a straight-in runway 06

. The Captain called for the "Descent

and "Approach" checklists

. While reading the checklist, the fasten seatbelt sign wa

switched on at 12

:37 :14

After reading the item "crew briefing" in the descent checklist, the F0 asked whether th

crew briefmg

would follow after the checklist was completed

. Seven seconds later

suggested

: "

. .

.or standard zero six?" to which the Captain responded with

: "Standard 06

111

.1 standby, 061

[Which means

: standard approach for runway

06,

localizer SL

on frequency

111

MHz

on standby, inbound

approach track 061 °

]

At 12 :37

:35

Schiphol

Approach informed

Schiphol

Tower that KL433 would make

straight-in approach for runway 06

Schiphol

Approach requested

Schiphol

Tower t

order the fire brigade to take position along the landing runway

Schiphol

Tower passe

this on to the NVLS duty manager who reported "ready" at 12

:38 :00

In the meantime,

Schiphol

Approach asked KL433 if they could give any details regardin

their situation and the Captain responded that they had an engine oil pressure problem i

engine no

. 2, but that the situation was under control . When asked by

Schiphol Approac

if the engine was feathered, the Captain stated that the engine was running in flight idle

This information was passed to

Schiphol

Tower and from there to the NVLS

dut

manager

At that time, the aircraft was descending through FL105 at 18 nautical miles

(nm)

fro

the airport and

Schiphol

Approach asked KL433 whether the distance-to-go was sufficien

for the landing procedure

. The Captain responded that it was sufficient

The F0 started with the approach checklist and, in response to the relevant checklis

item, he indicated to the Captain that for a standard approach, the approach speeds woul

be 113, 119 and 128 knots

. The Captain confirmed these speeds after which the approac

checklist was completed

The speeds mentioned by the F0 were the reference speeds for

V77120

(119

knots

)

niRESNO

Dits,

V„as (113

knots), an

VnNAL



V (128

knots)

These are reference speeds for a standard

two engine approach, related to aircraft weight

In the meantime

Schiphol

Approach had a separate working station operational

Schipho

Arrival working on a separate frequency, which would exclusively handle KL433

. A

:38

:48 KL433 was consequently instructed to contact

Schiphol

Arrival

Intermediate Approac

Passing FL075

Schiphol

Arrival informed KL433, that the surface wind was 250° with 1

knots and that the aircraft was number one for landing on runway 06

At that time, KL433 was 11

due west of Amsterdam and

Schiphol

Arrival vectore

the aircraft to a position for landing at runway 06 by instructing KL433 to fly headin

220

Schiphol

Arrival requested also the preferred direction of turn . KL433 confirme

heading 220 and replied that the aircraft was making a turn to the right

. In response t

the wind readout from

Schiphol

Arrival, the F0 informed the Captain that there would b

a tailwind component of 10 knots for landing on runway 06, which was acknowledged b

the Captain

Schiphol Arrival remained in contact with

Schiphol

Approach to make arrangements fo

separation with other traffic and at 12

:39

:37

Schiphol

Arrival instructed KL433 to sto

the descent initially at FL050 . As KL433 was already cleared to an altitude below th

transition level, the pressure altimeters were set to QNH (993 HPa) and had to be re

adjusted for the standard 1013

.2 HPa setting just before the aircraft reached FL050

Schiphol

Arrival then instructed KL433 to fly heading 240

. During level flight at FL050

the Captain stated to the F0, that the right hand oil pressure indicated a steady pressur

of more than 50 psi, which was confirmed by the F0, who also informed the Captain tha

he agreed with his decision to return to Amsterdam

. At 12

:40 :22,

Schiphol

Arriva

instructed KL433 to descend to 2,000 feet, which was confirmed by KL433

Passing 4,200 feet, while descending to 2,000 feet,

Schiphol

Arrival sent the followin

message

: "KLM433, you can steer left heading 060 for finals runway 06

. . .

wha

direction you will turn?" The Captain called out

: "Left", after which the F0 responded t

Arrival

: "We are turning over left heading 060, KLM433"

At 12

:41

:22 KL433 was informed by

Schiphol

Arrival that the aircraft had 12

nm to g

before landing and at 12

:41

:52 KL433 was offered the choice either to intercept th

localizer or to continue on heading 060 while Arrival would continue to provide rada

vectors

. KL433 replied to these options by just stating

"KLM

four three three"

In order to avoid any further frequency change for KL433

Schiphol

Arrival had agree

with

Schiphol

Tower that

Schiphol

Arrival would control KL433 until landing

. A

:42

:00

Schiphol

Arrival stated to KL433

: "You are cleared to land for this approach

ten miles to touch down", after which KL433 confirmed the landing clearance

Upon reaching 2,000 feet, at 12

:42

:00, thrust was applied to the

engine for the firs

time since KL433 started its descent from FL160 and the airspeed was reduced from 18

knots to approximately 155 knots

. At this time the F0 mentioned to the Captain

"Because you are flying flight idle, you probably have less problems than you might hav

had otherwise", to which remark the Captain responded with

: "Yes"

At 12

:42

:26,

Schiphol

Arrival instructed KL433 to fly heading 050 and to report runwa

in sight, stating that the distance to go before landing was 8

At 12

:42

:39, the F

reported

: "Runway in sight", which was confirmed by the Captain 4 seconds later

. Th

F0 also informed the CA that landing was imminent

At 12

:43

:06, KL433 intercepted the runway 06

ILS

localizer after which the gear wa

selected down and approximately 78% torque was applied on the

engine

. Shortl

thereafter the runway 06

ILS

glide slope was also intercepted, the flaps were set to 15

and the torque was reduced

. At 12

:43

:25, the aircraft was established on the runway 0

ILS

with the gear down and flaps set at 15°, and the Captain commanded for the landin

checklist

Final Approac

Landing flaps were set at 20° at time 12

:44

:03, just prior to passing the Outer Marke

(OM), at which time the landing checklist was completed by the F0

. Passing the OM, th

aircraft was established on the runway 06

ILS

in landing configuration and flying with th

Auto Pilot (AP) engaged

. Torque on the

engine was set at 28%, while the

engin

remained at flight idle . The Indicated Airspeed (IAS) at that moment was 142 knots an

was reducing to the target approach speed of 125 knots

At 12

:44

:22, while passing 1,080 feet Radio Altitude (RA) and with 127 knots IAS

torque on the

engine was increased to 60% in order to stop airspeed reduction

and

maintain a target approach speed of 125 knots

. Initially the airspeed decreased further t

120 knots and then increased to 130 knots

At 12

:43

:42 and at 12

:45

:12

Schiphol

Arrival stated the wind to be respectively 280° a

8 knots and 280° at 9 knots

. Both reports were confirmed by the F0, by clicking hi

microphone button

. At 12

:44

:05, on request of the Captain, the F0 stated that th

tailwind component was 8 knots

At 12

:44

:38, while the aircraft was passing 880 feet RA with the AP still engaged, th

F0 remarked

: "The trim is all the way to the left

. .

. He suggested to the Captain to se

the ruddertrim to neutral just before landing, to which suggestion the Captain responde

with

: "Yes, that will make it easier, doesn't it"

At 12

:45

:00, while passing 612 feet RA, the Captain disconnected the AP

At 12

:45

:02, passing 500 feet RA, landing clearance was confirmed by both pilots an

shortly thereafter torque on the

engine was reduced to 45% and airspeed wa

maintained at approximately 128 knots until - passing 300 feet RA - torque on the

engine was further reduced to 30% in order to obtain his final approach speed of 11

knots

. At that time, the aircraft was approximately 0

.6 dots below the glide path and pitc

was increased to correct the vertical flight path of the aircraft

The airspeed started to reduce and at 12

:45

:33, while passing approximately 230 feet R

with an airspeed of 120 knots, the F0 indicated to the Captain that he would position th

rudder trim to neutral to which action the Captain agreed

. At that time the aircraft was o

the glide slope . Shortly thereafter the pitch of the aircraft was decreased and consequentl

the aircraft became 0 .4 dots below the glide slope

. The pitch of the aircraft was increase

again for another correction of the vertical flight path, while torque on the

engine wa

increased from 30 to 40% . In the meantime the airspeed had decayed to 115 knots and a

:45

:41 the F0 stated

: "Mind your speed"

Passing approximately 120 feet RA, an aggressive increase in torque (from 40% to 65%

)

was applied, but hardly any additional rudder input was given to correct for asymmetry

After correcting the initial small rolling movement to the right, the aircraft was kep

wings level by significant aileron input

. The aircraft veered approximately 6° to the righ

and while passing 90 feet RA, just before the landing threshold, the aircraft positione

itself to the right of the extended centerline

. At 12

:45

:46, torque was reduced from 65

to 40%, which further reduced the airspeed to 110 knots

At 12

:45

:53, while

passing

45 feet RA,

flying

to the

right

of the

runway

at an airspeed o

110 knots, the Captain commanded

: "Going around

. .

.set torque, flaps seven, gear up"

Go Aroun

These commands, given by the Captain, were acknowledged by the F0

. At 12

:46

:00

torque was set at 98% on the

engine (the

engine remained at flight idle) and th

flaps started to move from the 20° position towards the 7° position

. No acknowledgemen

was given for the command "gear up", but the landing gear was selected up immediatel

after "flaps 7°" was selected

At 12

:46

:06, the flaps were at 7° . No conclusive data could be found on the

UFDR

confirm that the landing gear reached its fully retracted position, but it could be verifie

from pictures taken by witnesses that the landing gear functioned normally and that i

reached its fully retracted position approximately 8 seconds after the landing gear wa

selected up

Between 12

:45

:53 and 12

:46

:00, while the torque was increased from 40% to 98% n

additional rudder deflection was applied, but again the initial roll to the right and th

additional asymmetry were counteracted by significant aileron input up to maximu

control wheel deflection

Initially, the pitch of the aircraft was increased from approximately 4° to 7°

. At 12

:45

pitch was further increased to a maximum of 12°

. At that time the airspeed had decrease

to 105 knots and the sudden increase in pitch and associated increase in angle of attac

triggered the stall warning . The stall warning stopped at 12

:46

:00 when the pitch of th

aircraft was lowered to 6°

At 12

:46

:00, the airspeed had decreased to 97 knots

. At that time the aircraft started

shallow turn to the right with a progressively increasing bankangle

. At 12

:45

:58 som

additional rudder deflection was applied, but full rudder deflection was only reached a

:46

:06

At 12 :46

:03, the pitch of the aircraft had been increased again to 9° and the stall warnin

was triggered for the second time . Airspeed at this moment was 100 knots

. The stal

warning remained activated until the moment of impact

. During the last few seconds o

the flight the aircraft banked further to the right and airspeed decreased to less than 9

knots

. At 12

:46

:09 the aircraft crashed into the ground just outside

Schiphol

Airport wit

approximately 80° right bank

At 12

:46

:04

Schiphol

Tower informed

Schiphol

Arrival that KL433 was making a g

around and at 12

:46

:10 information was received that KL433 had crashed

At the same time a major alert was given and all flights to and from Amsterdam wer

stopped at 12

:46

:22

.2 Injuries to Person

Injuries

Crew



Passengers



Others

Tota

Fatal

2 0

Serious

0 9

Minor/None

Total

0 24

.3 Damage to Aircraf

The aircraft was damaged beyond repair

.4 Other Damag

The soil of the crash site was polluted with kerosene and an area of approximatel

9,000 m

agricultural soil had to be removed and replaced

.5 Personnel Informatio

.1 Captai

.5.1



Genera

Male



Age 3

Licence



•



Netherlands B2, no

. 92-0036, with Instrument Rating, Radi

Telephony and aircraft rating for the Saab 340

Type qualification

•



23 April 199

Last medical check



December 199

Total hours



2,60

Hours on type



▪



1,21

Hours last 90 days



Hours last 30 days



Joined

KLM Cityhopper

on 02-03-1992

.5.1



Duty and Rest Period

Duty and rest times in the period of 7 days preceding the accident flight

Date Code Duty Rest

Start

28/03/94

RTL

Reserve

.00

29/03/94

KL079

AMS-LUX-SXB 20

:35

30/03/94

KLO70

SXB-LUX-AMS 07

:20

:55

31/03/94

Off

duty

:00

01/04/94

Off

duty

:00

02/04/94

Off

duty

:00

03/04/94

RTL

Reserve

:00

04/04/94

RTB

Reserve

:00

04/04/94

KL43

KL433

AMS-SOU-AM

AMS-CWL-AMS

118

:39

:15

—

Originally, the captain was scheduled for reserve duty on 4 April 1994, but this schedule wa

changed to flying duty on the evening of the day preceding the accident . During the previous 3

months, the captain had flown 7 flights from Amsterdam

(AMS)

Cardiff (CWL) vice versa

1 1

.5.1



Medical Histor

While exercising the privileges of his licence, the captain had to wear correcting glasses

No other restrictions applied to the licence of the captain

. At the time of the accident th

captain was wearing contact lenses

.2 First Office

.2 .1



Genera

Male



•



Age 3

Licence



Netherlands B3, no

. 90-0190, with Instrument Rating, Radi

Telephony and aircraft type ratings for Piper PA-31 an

Saab 340

Type qualification

•



10 March 199

Last medical check



May 199

Total hours



1,71

Hours on type



•



1,33

Hours last 90 days



Hours last 30 days



3 5

Joined

KLM Cityhopper

on 27-01-1992

.5.2.2



Duty and Rest Period

Duty and rest times in the period of 7 days preceding the accident flight

Date

Code Duty

Rest

Start

28/03/94

KL401

AMS-BRE-AMS 04

:15

29/03/94

KL407

AMS-BHX-AMS

:31

:10

30/03/94

VT 1

Simulator

Typ

Recurrent

:06

:00

31/03/94

Route

day

:00

01/04/94

Off

duty

:00

02/04/94

Off

duty

:00

03/04/94

KL42

KL023

AMS-BRU-AM

AMS-MMX-AMS

:15

:50

04/04/94

RTB

Reserve

:00

04/04/94

KL43

KL433

AMS-SOU-AM

AMS-CWL-AMS

:25

:15

—

Originally, the F0 was scheduled for reserve duty on 4 April 1994, but this schedule wa

already changed to flying duty 3 days preceding the accident flight

. During the previous

months, the F0 had flown 4 flights from Amsterdam (AMS) to Cardiff (CWL) vice versa



Medical Histor

There were no restrictions imposed on the licence of the F0

.6 Aircraft Informatio

1.6.1



Genera

Type

: SAAB 340

Registration

: PH-KS

Serial no

: 19

Acceptance date

: 26 June 199

Certificate of Airworthiness

: No

. 4115, valid until 2 June 199

Total airframe hours

: 6,55

.2 Engines

The SAAB 340B is equipped with two General Electric CT 7-9B turbo-prop engines

each developing a maximum of 1,870 shaft horsepower at 22,000 power turbine RPM

The CT7-9B has a gas generator powering a free power turbine directly coupled to th

propeller gearbox

The engine has two independent oil systems

: the propeller gearbox oil system and th

power unit oil system . Each oil system has two separate oil pressure measuremen

systems, which provides for both a cockpit oil pressure indication and low oil pressur

warning light

. The oil pressure indication comes from a pressure transducer to the cockpi

gauge, whereas the low oil pressure warning light is activated by a pressure switch

Engine operation is basically manual, using the power lever and condition lever (fo

propeller pitch and fuel), with associated automatic fuel metering and automatic protectio

systems

. The system also incorporates a Constant Torque On Take off (CTOT) and a

Automatic Power Reserve (APR) function . The CTOT regulates fuel flows beyond th

power lever position to a preselected value

. The APR provides 7% extra thrust on th

good engine, in case of a powerloss on the other engine

The SAAB 340B is not provided with an Automatic Throttle System

. Such a system is no

compulsary

.3 Propeller

The engines are equipped with Dowty Rotol constant speed propellers

. These are variabl

pitch, single acting, full feathering, reversing propellers each with four composite blades

The propeller is hydraulically controlled by the propeller pitch control (condition lever)

1.6

.4 Engine and Propeller Histor

LEF

Engine

Gearbox

Propelle

Serial number

GE-E-785137

UDAG-0739

DRG/10173/8

Total time

6,517

4,606

6,88

Total cycles

6,636

4,63

Hours since major repair

2,245

1,665

Cycles since major repair

2,149

1,61

RIGH

Serial number

GE-E-785421 UDAG-0691

DRG/1385/9

Total time

3,688

6,067

4,73

Total cycles

3,553

6,08

Hours since major repair

193

Cycles since major repair

173 173

.5 Weight and Balanc

Comparing the actual boarding list with the computer loadsheet, a discrepancy of minu

one passenger was found (21 instead of 22)

This information was corrected on th

loadsheet by the flightcrew and a take off weight of 12,589 kg (27,754 lbs) was calculate

[maximum take off weight is 13,155 kg (29,000 lbs)]

During the investigation, this take off weight was recalculated on a manual loadsheet t

check the figures known to the flightcrew

. The recalculation revealed a take off weight o

12,603 kg (27,785 lbs)

. The difference in outcome between both calculations was no

traceable, but had no influence on the speeds used by the crew for take off and landing

The total amount of fuel used during the flight was 199

.5 kg (440 lbs) (UFDR data) an

the weight of the aircraft at the moment of the accident was 12,404 kg (27,345 lbs)

. A

the moment of the accident the amount of fuel in the tanks was 1,600 kg (3,527 lbs)

At the time of the accident the centre of gravity of the aircraft was at 47

.2 loaded index

which was within the limits of the loadsheet envelope, between 36 and 52

.6 Flighthandling and Performance aspect

The SAAB 340B was certificated according to the airworthiness regulations o

FAR/JAR Part 25

Calculations, using data provided by the manufacturer, showed that in the configuration

Flaps 7°, landing gear up, one engine shut down and propeller feathered, the minimu

control speed under the prevailing weather conditions (temperature and altitude) was 9

knots

. With one engine at flight idle (propeller not feathered), the calculated minimu

control speed was equal to or less than 103 knots

. At the moment the go around wa

initiated the speed was 110 knots

Under the actual conditions (actual weight, temperature, altitude) the available clim

performance deteriorated considerably with the

engine in flight idle due to the hig

propeller drag

. The calculation showed that in this case the climb performance in th

landing configuration (20° flaps, landing gear down) was approximately 0

.4% (50 fpm

)

and in the go around configuration with flaps 7° and landing gear up, the achievabl

climb gradient was approximately 2

.3% (250 fpm)

.7 Meteorological Informatio

General weather conditions for

Schiphol

on 4 April 1994, at approximately 12

:50 UTC

Behind a cold front clear, cooler, and unstable air was to determine the weather in Th

Netherlands

. At 13

:00 UTC an active trough was positioned over the southern part of th

North Sea, and was moving eastward with a speed of approximately 30 knots

Weather conditions at

Schiphol

Surface wind



270°/likt Temperature 9° C Visibility > 10 k

Wind at 1,000 ft



250°/20kt Temperature 6° C Visibility > 10 k

Weather



Clouds



•



2/8 Cu, basis 1,500 ft, tops 3,000 f

4/8

Sc,

basis 3,500 ft, tops 9,000 f

5/8

Sc,

basis 5,000 ft, tops 9,000 f

0° C level



•



4,500 f

Ice formation



In showers moderate to severe, in

moderate .

Turbulence



▪



In and near showers moderate, in trough severe

Convective activity



During final approach of KL433 the surface wind was reported to be 280° with 8 knot

and 280° with 9 knots

.8 Aids to Navigatio

All navigational aids relevant to the accident flight were operational and functionin

within their prescribed limits at the time of the accident . There was no NOTAM informa-

tion regarding these navigational aids

The runway 06

ILS

glide path was flight tested on 13 December 1993 and on 4 Marc

1994

. The runway 06

ILS

localizer was flight tested on 6 April 1994

. During all fligh

tests the runway 06

ILS

was found to operate within the limits for Category III operation

.9 Communications and Recording

.1 Air Traffic Contro

The Radio Telephony

(RT)

callsign of the flight was

KLM

433

. Standard Very

Hig

Frequency (VHF) communication was used between the aircraft and ATC and th

technical quality of the communication recordings with all ATC units involved wa

normal

.2 Ground Operation

Ultra High Frequency (UHF) communications were used between the Tower, the

NVL

Duty Manager, the Police, the fire brigade and all other personnel involved in pos

accident operation and coordination

Shortly after the alarm was given that the aircraft had crashed, a malfunction of th

Airside emergency communication system occurred, which persisted for about 5

minutes

. Due to this malfunction no communication was possible between Airside Contro

Center and the fire brigade units at the scene of the accident, resulting in delays i

coordinating actions with external fire fighting and rescue units

. Communication betwee

fire brigade units was not affected and functioned normal

.10 Airport Informatio

During the flight of KL433 from and to

Schiphol,

runways 24 and OIL were used fo

departures, while runway O1R was the main landing runway, according to the preferentia

runway system

. Runway 06/24 is 3,250 by 45 meters, runway 01L/19R is 3,300 by 4

meters

The airport field elevation is 11 feet below mean sea level, the threshold elevation o

runway 06 is minus 3

.6 feet

. The threshold crossing height of runway 06 during I L

approach is 55 feet

.11 Flight Recorder

The aircraft was equipped with a Fairchild CVR and a Sundstrand UFDR . Shortly afte

the accident both recorders were removed from the aircraft at the accident site by th

Schiphol

airport fire brigade on order of the Netherlands Aviation Safety Board

Data recorded by the CVR were of good quality . The only remark to be made concern

channel 4 (area microphone)

: the noise of the engines and propellers were recorded muc

louder than other cockpit sounds, which were hardly audible on track 4

. The KLC SAA

340B aircraft was fitted with "hot" microphones and all cockpit sounds were als

recorded and clearly audible on track 2 (FO) and track 3 (Captain)

The data recorded on the UFDR were of excellent quality

. Raw data were converted b

use of a mainframe program

. The only parameter on the UFDR which was not correctl

recorded was "GMT"

. Apparently the timebase, used

by the Flight Data Acquisition Uni

(FDAU), was 26 minutes and 55 seconds off

The CVR does not contain any time reference, but accurate timing has been establishe

using recordings of ATC communications

. The latter were recorded together with a time

base on the ATC recording system

. Data on the UFDR were time-synchronized wit

events on the CVR

. The main synchronization event was the moment during fina

approach when the auto pilot was disconnected

. This event was recorded by two discrete

on the UFDR and an identifiable sound was recorded at the same time on the CVR

The UFDR readout plots are contained in appendix 2

.12 Wreckage and Impact Informatio

.12

.1 Accident Site Descriptio

The accident site was located just outside

Schiphol

Airport, in agricultural terrain

. Th

terrain condition of the accident site was wet and muddy

. The wreckage came to res

approximately 560 meters right of the runway centreline and 1,125 meters beyond th

threshold of runway 06

.12

.2 Aircraft Wreckage Descriptio

The aircraft hit the ground in a steep right turn with a slightly nose-low attitude an

approximately 80 ° bank to the right

. The ground speed at the moment of impact was 9

knots

. During the last moments of flight, the landing gear was up and the flaps wer

extended at 7°, as selected by the F0 when the go around was initiated

. The estimate

damage sequence was reconstructed and is described below

The

wingtip hit the ground and was ripped from the wing

the outer panel of the outerwing broke off

the inner panel of the outer wing hit the ground and broke off outboard of th

engine

the

engine hit the ground, propeller blades separated, engine and inner win

section broke off from the center section

the

inner wing section was projected in such a way, that it hit the

side of th

fuselage

the

horizontal

stabilizer

tip

hit the

ground and

the stabilizer was bent

approxi-

mately 20° upwards

the

side of the cockpit and

side of the forward part of the cabin hit th

ground and were damaged

the

wing attachment fittings and aft cross link broke off

the aircraft without the

wing rolled over to the left due to forces of inertia

the aircraft yawed to the right and the fuselage rolled over onto the

wing

pivoting around the

wing attachments

. The

stabilizer and elevator hit th

ground and were ripped from the fuselage

the aircraft came to rest after having turned approximately 100° to the right from th

impact direction, with the fuselage lying on its left side on the left wing, blockin

the two

exits

the total length of the wreckage trail was 110 meters

During the disintegration of the

wing, the contents of the

fuel tank vaporised an

ignited

. The cloud of vaporised kerosene burned for only a few seconds

The

wing section with its fuel contents remained intact and no further fire developed

For wreckage and wreckage distribution, see appendix 1

1.12

.3 Technical Examination of the Wreckag

.12

.3.1

Genera

A full technical investigation was conducted with the assistance of specialists of th

aircraft engine and propeller manufacturers

All aircraft parts and control surfaces were accounted for at the accident site

. The aircraf

damage was consistent with the exposure to the excessive loads during the impac

sequence and the effects of the subsequent fire

. No pre-existing defects likely to hav

contributed to the accident were found

.12

.2 Flight Control

The flight control systems for rudder, ailerons, elevators, flaps and gust lock system hav

been inspected regarding their mechanical status

. Many broken off and damaged part

were found

. There was no indication of any malfunction in these systems

Full flight control movement is checked in the "Cockpit Preparation" checklist, prior t

engine start up, which is not registered on the UFDR . In the "Before Take Off" checklis

the flight controls are again checked, to verify gustlock release

. The UFDR registratio

showed that the rudder was used to about half the full travel

; ailerons and elevator wer

checked to about 80% of their respective full travel

The rudder limiter crank was found in the retracted position, offering unlimited rudde

travel

. During the flight neither aural nor visual rudder limiter warnings occurred, a

evident from the CVR

. Therefore it has been concluded that the rudder limiter did no

restrict rudder travel during the final approach and go around

1.12 .3.3

Engines and Propeller

The examination of the engines and propellers did not reveal any pre-impact damages o

malfunctions

.12 .3 .4

Engine Instrument

The oil pressure and temperature instruments and relevant transducers of both engine

were tested

. The

engine oil pressure switch was found to have failed internally

The switch was shorted, resulting in intermittent illumination of the oil low pressure light

All other tested instruments and transducers functioned correctly, with some mino

tolerance exceedances, most probably due to impact forces

.12

.5 Flight Instrument

Some of the flight instruments sustained severe impact damage to such a degree tha

testing was not possible

. These instruments were the Captain's altimeter, Vertical Spee

Indicator (VSI), airspeed indicator and the Air Data Computer

. The FO's altimeter an

VSI showed deviations as a result from impact damage

. The FO's airspeed indicator

standby altimeter and airspeed indicator were found in serviceable condition

Given the flight recorder and CVR registrations, together with the flightcrew's actions

the Board is of the opinion that the Captain's instruments were working correctly

.13 Medical and Pathological Informatio

.13

.1 The Cre

The

side (Captain's side) of the cockpit was almost undamaged . Investigation of th

cockpit interior revealed a badly damaged pedestal with broken handles of both throttle

and condition levers . The postmortem medical examination of the Captain and the damag

observations in the cockpit both revealed that the Captain was not wearing his shoulde

harness and that

most

probably

was

smashed

against the handles

the pedestal

The

side (FO's side) of the cockpit was extensively damaged and consequently th

F0 suffered severe injuries

. As a result of the impact forces the F0 suffered fro

amnesia

. Therefore he was not able to give any useful information regarding the acciden

flight

The CA was seated on the

forward side of the aircraft, facing aft

. His seat was foun

in good condition

. The CA suffered only minor injuries, most of them caused by debri

of the

galley area, which disintegrated upon impact

.13 .2

The Passenger

The passengers were seated throughout the aircraft

. Most of the minor or uninjure

passengers were seated on the

side of the cabin

. The serious injured passengers wer

seated on the

side of the cabin

. Injuries varied from broken legs and arms to cuts an

bruises, pelvis fractures and brain concussions

. Of the wounded passengers, 8 wer

seriously injured and 11 suffered only minor injuries

The two deceased passengers were seated at 3C and 4C which were located close to th

impact point of the crash

. See also section 1

.15

. Both passengers died instantly, or ver

shortly after the accident, due to severe traumatic injuries

.14 Fir

The blockfuel of 1,800 kg of Jet Al fuel was equally divided over both wing tanks

. A

the time of the accident, approximately 200 kg of fuel had been used

The right wing was torn off the aircraft upon impact and disintegrated

. The fuel from th

tank of this wing ignited immediately

. The fuselage and the left wing remained connecte

to each other when they were forced away from the ignited fuel

. Although severel

damaged, no fuel was leaking from the tank in the

wing

The main fire (from the disintegrated right wing) burned out after a few seconds, an

only some small flames remained visible at the debris of the right wing, spread aroun

the main parts of the aircraft

The fire brigade arrived at the scene of the accident about one minute after the crash

too

place

. They were on alert and were positioned alongside the landing runway, approxima-

tely 500 meters from the accident site

. At the scene of the accident, the fire brigade use

the following fire fighting equipment

4 Crash tenders

1 Rapid Intervention Vehicle (RIV)

1 water canon vehicle

1 emergency assistance vehicle

1 equipment container vehicle

The aircraft crashed in very wet and agricultural terrain consisting of greasy clay

. Due t

the nature of the terrain, and the fact that the main wreckage was not on fire, no risk wa

taken with the heavy vehicles to reach the wreckage of the aircraft

. Fire fightin

personnel, equipped with portable fire extinguishers, hurried to the wreckage, while hose

were rolled out . The small remaining fires were extinguished by the fire brigade and n

other new fires ignited . During the rescue operations, the hoses remained permanentl

manned and aimed at the wreckage, until all occupants of the aircraft were removed an

there was no more risk of new fires to ignite

. Total fire fighting and protection actio

lasted several hours

As a result of the nature of the agricultural terrain rescue vehicles were unable to ente

1—L



)-L



o c



Saab 340E Passenger Cabin Compartments

Seating of passengers at moment of accident

.15

.2 Interior Damage and Survivabilit

.15

.1 Genera

The following paragraphs, describing the survivability aspects are based on the status o

the aircraft as examined in the recovery hangar, after salvage

. It is known, that during th

rescue and salvage operations extensive further damage was inflicted to the wreckage

This reportedly included the cutting of one or more holes in the fuselage, the cutting o

seat legs to separate them from the wreckage, the cutting of some of the wing-to-fuselag

joints and the removal of items such as baggage

The impact point on the aircraft was at the

side of the aircraft, with most of th

severe structural damage (besides the disintegrated

wing) at the

side of th

cockpit and first forward part of the

side of the fuselage

.15

.2 Cockpi

The cockpit was configured in a standard two-pilot configuration, with an observer seat i

the cockpit-to-cabin passage

. The Captain was seated in the

seat, while the F

occupied the

seat

The

side of the cockpit showed severe impact damage

. The

side was virtuall

undamaged and all four cockpit windows were intact

. An examination of the cockpi

interior showed the main instrument panel, the glareshield panel, overhead panels and th

left side panels all in position

. The center panel, although still in position, was moved a

its rear end and to some extent to the left

. The

side panels were displaced and here

small hole was found

. The two cockpit backwalls were displaced

. The

backwal

(consisting of the avionics rack with

galley and the cabincrew seat attached) wa

moved slightly forward

. The

backwall was moved

the left and rested against th

backwall, with the folded observer seat in between

. Both pilot seats were stil

attached to the floor rails and were virtually undamaged

In order to ascertain the correct seating position of both pilots, an attempt was made

determine the position of both pilot seats using impact marks on the seat rails

This was not possible due to the large number of impact marks present

Using photographs of the cockpit interior, taken immediately after the accident it could b

concluded that the pilot seats were in a correct position, enabling both pilots

use th

flight controls to full extent

The seatbelts of both pilot's seats as well as the inertial reels functioned correctly whe

tested after the accident

. The screwdrive adjustment

the FO's

backrest had been drive

past its limit, with the consequence that the retaining function of the shoulderstraps wa

lost

. The cause was traced to be an inadvertent actuation of the backrest release handle

on the right hand side of the seat as a result of the deformation of the

cockpi

sidewall

.15

.3 Galle

The

galley was displaced inboard with most doors open

. The red turn buckles wer

generally found in the closed position

. The

galley was basically still in position

. Al

drawers were found in the closed position

. The red turn buckles were found in the ope

position

1.15 .2

.4 Cabi

The cabin was configured with 11 rows of 3-abreast passenger seats, with double seats o

the

side and single seats on the

side of the aisle

. The cabincrewmember seat wa

virtually undamaged

. The seatbelt and shoulderharness were serviceable

. The foldabl

chairs were in their stowed position

The underfloor structure of the cabin, forward of the wings, was attached, but the floor

and seat rails were missing

. Seats were missing up to and including seat row 6 except fo

seats 4B and 5A, which were still in place, with one leg attached

the rails

. All seat

from row 7 and aft were still in place, with all legs attached and without any significan

damage, except for seat 7A

. The side walls were still attached from seat row 9 an

further backwards

The luggage bins and Passenger Service Unit (PSU) panel row on the

side wer

attached, except that close to the fuselage break the bins drooped down approximately on

feet

. There were four bins in the fuselage section

.15

.5 Exit

The cockpit has two means of escape

: An overhead hatch and via the cabin

The cabin has four means of escape : The forward passenger door, which qualifies as

type I passenger emergency exit, a type II emergency exit on the opposite side and tw

type III emergency exits overwing adjacent seat row 6

As a result of the deformation of the

side of the cockpit, the passage between th

cockpit and the cabin was obstructed . Evacuation/rescue of the pilots had to be conducte

through the overhead escape hatch

The position of the aircraft after impact, lying on its

side, precluded the use of th

main passenger door as well as the

emergency overwing exit for evacuation

. The

overwing exit was difficult to

use, being "overhead" at that time

. Rescuers cut

throug

the already deformed

side of the fuselage, between the forward exit and the overwin

exit, in order to be able to extricate the occupants

.16 Tests and Researc

1.16

.1 Procedure

The investigation revealed that differences exist between the

KLM

Cityhopper

SAA

340B Aircraft Operations Manual (AOM) and the Manual issued by the manufacturer

These will be discussed in paragraph 2

.16

.2 Pilot Selection and Trainin

.16 .2

.1 Main requirements pursuant to Netherlands Aviation La

Requirement for the issue of a personnel licence for airline operation

. For aircraft with MTOW up to 5,700 k

Commercial Pilot Licence (CPL-B3) with Instrument Rating

(IR

)

At least a total of 200 hours, of which

at least 150 hours Pilot in Command (PIC), of which 50 hours cross-country flights

;

at least 40 hours Instrument Flying (IF)

;

- at least 5 hours instruction during night

. For aircraft with MTOW up to 20,000 k

Senior Commercial Pilot Licence (SCPL-B2) with

At least a total of 900 hours, of which

at least 200 hours PIC

;

at least 25 hours PIC (or 50 hours as FO) at night

;

- at least 10 hours PIC (or 20 hours as FO) during cross country flight at night

;

at least 20 hours IF

For airline operations with SAAB 340B (MTOW 13

.155 kg) the law requires

For the Captain a Senior CPL (SCPL-B2) with

and type rating

;

For the First Officer a Commercial Pilot Licence (CPL-B3) with

and type rating

.16

.2 KLC Initial Requirement

All pilots will enter KLC as F0 and depending on their progress will eventually b

promoted to Captain

Apart from age limits and education requirements KLC requires

Practical CPL-B3 with

Licence

;

Theoretical Netherlands SCPL-B2/B1 Licence

;

Multi-engine rating, with

If in possession of a Netherlands CPL, 50 hours on medium, Netherlands registered

twin engine aircraft

If not in possession of a Netherlands CPL, 250 hours on medium twin engine

aircraft

. In addition a Netherlands twin rating must be obtained

.16 .2

.3 KLC Selectio

Selection of Pilots for KLC consists of

Psychological test at the Netherlands Aerospace Medical Centre (NLRGC)

Psychological test

"Psychotechniek"

Psychodiagnostic test at Mr

. H

. Havinga (psychiatrist)

- Medical test at

KLM

Medical Services

Security Check

Interview

.16

.4 KLC Type Qualificatio

After passing the KLC selection criteria the pilots will start with the type qualificatio

training which for the SAAB 340B consists of

Flight Simulator Training at FST BV

Computer Based Technical training

Simulator Training SAAB 340B, consisting of 2x6 sessions of approximately 4 hours

24 hours as

and 24 hours as PNF

Examination Group I/II/III' on Simulator

Aircraft training on SAAB 340B aircraft

Examination Group IV

on aircraft

Route Training

Route Check

When the route check is completed and assessed as Standard or better (See also paragrap

.16 .2

.7) the pilot is ready for line flight duties with a normal crew

.16 .2

.5 KLC Captain's Training/Qualificatio

All pilots will initially be employed for a minimum of approximately one year as F0

When a F0 is selected for Captain's training a few flights with a flight instructor are t

be made

Command Promotion Assessment Forms are used and when the F0 is assessed a

Group I

: Preflight preparatio

Group II

: General flyin

Group III : Procedure

Group IV

: Circuits and landings

"suitable" the Captain's training starts

This training consists of

6 hours Simulator Training (3 sessions of 2 hours), during one of these sessions

Crew Proficiency Check is performed

2½ hours aircraft training

Route Training

Examination of handbooks

When the training is completed and assessed as Standard or better (See also paragrap

.16

.7) the F0 will be promoted to Captain

.16

.6 RLD Inspection of KL

RLD supervises all operators and conducts spot checks on all aspects of operation on

regular basis

. The last inspection of KLC was conducted on 15 July 1993

. This inspectio

was specifically directed to simulator training with regard to SAAB 340B Category I

operations

1.16 .2

.7 KLC's Assessment Procedure of Proficiency Check

Assessmen

Assessment on the various subjects of proficiency checks is graded with the followin

abbreviations

: Above Standar

S +

: Standard Plus (i .e

. the upper portion of the standard band

)



: Standar

S-

: Standard Minus (i

. the lower portion of the standard band

)

: Below Standar

Standard Performanc

Standard performance is difficult to define

. It reflects the required quality level a

deducted from explicit requirements arrived at by the company, after careful considerati-

The minimum performance accepted by the company corresponds with "Standard Minus"

The "Standard Minus" performance level

Does not equal the minimum level required by law

; in practice the "Standard Minus

performance level is much higher

Is a safe and

acceptabel

performance level

; "Standard Plus" and "Standard Minus

should be seen as variations in the "Standard Band", nothing more

. It is meant t

indicate the pilot his/her (relative) strong and less strong points

The average level of performance is in no way related to the standard required

A proficiency check performance reflects a momentary observation

; previous experienc

may not be of influence on the assessment

.16 .2

.8 Training/Qualification Captain of Flight KL43

Date

Examination

Resul

31-03-199

09-04-1992

Type rating SAAB 340B Group I, II, II

(Simulator

)

Type

rating

SAAB 340B Group I

(Aircraft)

Faile

16-04-1992

Type rating SAAB 340B

Passe

25-11-1992

Proficiency check simulator (FO)

Passe

24-03-1993

Proficiency check en route (FO)

Passe

01-09-1993

Selected for Captain's trainin

September 1993

Crew Management Course 1

30-09-1993

Proficiency check simulator

Passe

27-09/17-1

1993

Captains training

en route

17-11-1993

Promoted to Captain

Proficiency

checks as

Captain

not yet due

.17 Organizational and Management Informatio

KLM Cityhopper

is 100% affiliated with

KLM

KLC has its own operational responsibili-

. The operation department is headed by a KLC manager of flight operations, wh

reports directly to the KLC Managing Director

. KLC's operational structure is based o

the specific demands of the regional airline environment

. KLC mirrors, where applicable

the professional standards of

KLM

On April 1, 1991,

NLM Cityhopper

Ltd and Netherlines Ltd merged into one compan

under the name of

KLM Cityhopper

Ltd

. After this merger, operational differences whic

existed in the two regional airline companies, had to be taken care of

. In addition

standardization of the different aircraft types within KLC had been part of the manage

ment task already

Recruiting and selection of pilots is conducted independently, with

KLM

standards use

as a guideline

. KLC has its own training program and simulator contracts

.18 Additional Informatio

The Air Branch of the Netherlands State Police assisted with questioning witnesses an

obtaining information for the investigation

.19 Useful or Effective Investigation Technique

Not applicable

ANALYSI

.1 Oil Pressure Warnin

Post crash examination of both engines did not reveal any pre-existing defects whic

could have affected normal engine operation . No evidence was found of any degradatio

of power, other than initiated by the pilot

. Examination of the pressure indication relate

components of the

engine oil system revealed that the pressure switch closed as

result of an internal intermittent short circuit . No evidence was found of any malfunctio

of the oil pressure transducer

2.1

.1 Technical Aspect

From the information available, it can be concluded, that the

engine oil pressur

CWP light illuminated as a result of a short circuit in the oil pressure switch

. This shor

circuit closed the switch and as a consequence the oil pressure warning light on the CW

was activated

. The

engine oil pressure transducer was found operating normal and i

must be concluded that the actual engine oil pressure was correctly presented on the

engine oil pressure indicator in the cockpit

2.1

.2 Flightcrew Handling of Oil Pressure Warnin

At 12

:30

:46 the Master Warning sounded for the first time

. The F0 immediatel

announced

: "Right engine oil pressure", confirmed by the Captain with

: "Check" . Th

Captain then slowly retarded the

power lever to the flight idle position

. Retarding th

power lever does not form part of the ECL procedure

. Possibly this was done with th

intention to prevent damage to the

engine

. As a result of this action the oil pressur

of the

engine decreased, which is normal when a large power reduction is applied

The flightcrew commenced with the ECL procedure as follows

[Translated version of relevant part of the CVR transcript

]

Time (UT

Source

Transcrip

:30:58

Captain Take actio

:31:00

Take action

. Emergency checklist

. Engine and propeller engine oil pressu

re low

. .

. 15

:31

:16

15B

. .

. engine oil pressure low, engine oil and prop oil pressure

. .

. checke

Well, engine oil pressure

that is this one, this one is slightly lower tha

the other one, but

. .

:31:32

It is decreasin

:31:33

Captain

:31:34

Yes, it is decreasin

:31

:37

only prop oil pressure, apply

. . .

only prop oil pressure low

apply propeller oil pressure low procedure, well

. .

. that

not the case

. .

2 9

:31:43

Then next

. .

. engine oil pressure control warning panel light on

. .

. or, engin

oil pressure below thirty ps

:31

:54

Captain That is not the case

:31

:57

Captain

But it is still normally in the green, that is what's so strang

:31

:59

That's funny, isn't it

:32

:00

Captain

:32:01

It is decreasing

. . .

[captain's first

name] engine oil pressure light on

. .

:32

:12

Captain

Yes, but we are not going to continue with this

. . .

Both pilots concluded that the

engine oil pressure was lower than the

engine oi

pressure and furthermore that the

engine oil pressure was decreasing

. Neither pilo

realised that the lower and still decreasing

engine oil pressure was most probably

result of the retardation of the

power lever, still continuing at this stage

. The F

continued with the engine oil pressure low procedure in the ECL

[Translated version of relevant part of

the

CVR transcript

]

Time (U7'C)

Source

Transcrip

:32:13

No, no, no, no, no, engine oil pressure

. .

., well light

below thirty psi

that

not the case

. So one

of two things

. If

so, than you may continue

but

they are both on,

so if

the light

on and the pressure

below thirt

psi, then

must be shut down

:32:33

Captain

:32

:37

Captain

Well, what do we have? Is it an,

. .

.above

fifty

:32

:41

:32

:42

Captain

And we

. .

. [set] the warning pressure is

. .

:32

:43

Yes, the light

. So the

light is

on, or below thirty, well

. . .

:32:50

Captain

Continue normal operatio

:32

:51

The redundancy in the engine oil low pressure indication system is to prevent a situatio

where an incorrect indication by the warning light or an incorrect indication of th

pressure indicator could lead to the wrong conclusion . Flightcrew action indicates tha

both pilots did not understand the system logic

After completion of the ECL procedure both pilots acknowledged that the

engine oi

pressure was above 30 psi and that normal operations could be continued

2.2

Decision Making Proces

2.2

.1 Genera

The ECL procedure was concluded with both pilots agreeing with the instructio

"continue normal operation"

. The ECL phraseology "continue normal operation" althoug

not specified in the ECL or the KLC AOM should be interpreted as an indication that th

flight can be continued using normal engine operation and normal flight techniques

. I

does not necessarily mean that the flight should proceed to its destination

.2 Decision to Return to Amsterdam Airpor

Considerations not to continue to the destination may be various and could have been fo

instance a possible maintenance delay or dispatch restrictions once landed

. However, fro

the CVR, there are no indications that these considerations played a role in th

flightcrew's decision to return to Amsterdam airport

The KLC AOM was not consulted for possible dispatch restrictions

From the CVR conversation it can be concluded that the Captain remained in doub

whether his decision to return was correct

.3 Decision to Maintain Flight Idle on the

Engin

Although the flightcrew diagnosed the problem and concluded "continue normal operati

on" the Captain kept the

engine running in flight idle

. If the flightcrew would hav

had any serious doubts about the condition of the

engine they should have carried ou

the engine shut down procedure followed by the

OEI

checklist procedure

. The decision b

the Captain not to use the

engine at this stage of the flight may have been influence

by his prior experience as F0 with an emergency resulting in a return to and landing a

Amsterdam under similar conditions

. As it is, the reasons for this decision were no

discussed between the pilots and the

engine was left operating in flight idle

The crew briefing during the descent would have been the last opportunity for the pilot

to realise the consequences of an approach with an engine in flight idle

. However as th

engine was not actually shut down, they did not consider the situation as an

approach

. Rather than discussing the situation the Captain simply stated, on the suggesti-

on from the F0, "standard 06, 111

.1 standby, 061" and consequently the standard Al

Engine Operative (AEO) procedure with associated threshold speeds was followed

From the CVR at 12

:42

:21 and 12

:42

:26 one can derive that both pilots were of th

opinion that they would have less problems handling the aircraft keeping one engine i

flight idle

[Translated version of relevant part of the CVR transcript

]

Trine

(UITC)

Source

Transcrip

:42

:21

I also

think, that because you are flying

flight idle, that because

tha

you have less problems than you might have had otherwis

:42

:26

Captain

Yes

The above conversation was to all probability related to a comparison with a situatio

whereby one engine is shut down and the propeller feathered

. It illustrates the lack o

knowledge of operations with one engine in flight idle and it can be concluded that bot

pilots were not aware of the consequences related to making an approach with one engin

in flight idle

2.2

.4 Choice of Runway 0

After contacting

Schiphol

Approach, flight KL433 was asked to advise on their preferenc

for runway 06 or runway O1R

. The Captain decided on runway 06

. Even if at that tim

the Captain did not fully realise that by his choice of runway 06 he accepted a tailwin

approach/landing situation, 3 minutes later this fact was pointed out

him by the F0

. H

acknowledged this information

By his choice of runway 06 the Captain accepted a tailwind component which, thoug

within limits and acceptable under normal conditions, is not recommendable in a singl

engine situation as it aggravates the speed stabilization problem

.3 Aircraft Handlin

2.3

.1 Descen

Due

the tailwind component on return the aircraft was

too

high for a straight-in landin

and

Schiphol

Arrival had to vector KL433 into an S-turn in order to correctly position th

aircraft for the

ILS

approach on runway 06

. The too high position of KL433 in relation t

the distance resulted in a descent with both engines running in flight idle

. As a conse

quence the pilots were not confronted with an asymmetrical power setting until just prio

to the final approach

From the moment power was applied on the

engine the pilots had little time t

become accustomed to the unusual flight condition with high asymmetric drag

. Thi

resulted in a non-stabilized power/airspeed situation when entering the approach phase o

the flight

2.3

.2 Final Approac

The final approach was started when the flaps were extended to 20°, just prior

passin g

the Outer Marker at 1,300 feet RA

The aircraft was established on the

ILS

for runway 06 and was flying with the autopilo

3 2

engaged

. Airspeed/power/pitch stabilization had still not been achieved

The IAS was reducing from 142 knots to the target approach speed of 125 knots and

engine torque was kept at 28%

While descending through 1,080 feet RA at 12

:44

:22

engine torque was slowl

increased to stop the speed reduction, reaching 60% at 12

:44

:42

. The

engine wa

kept at flight idle

. The IAS however further reduced to 120 knots and then started t

increase

. At about 600 feet the autopilot was disconnected

. The IAS increased to 13

knots and the aircraft became high on glidepath

. The Captain gradually reduced torque t

approximately 30%, allowing the IAS to reduce and the aircraft to get back on glidepath

At approximately 230 feet the ruddertrim was neutralized

When the aircraft became low on glidepath the Captain increased pitch and advanced th

engine torque to 40%

. This power increase was insufficient and combined with th

increased pitch resulted in a speed decay below the planned threshold speed of 119 knots

At 12

:45

:41 the F0 warned

: "Watch your speed", on which the Captain reacted with

brisk increase of the

engine torque to 65%

The aircraft yawed to the right and was displaced to the right of the runway

. Th

Captain, probably in a reaction, pulled the power lever back to 40% and realising, that

landing from this position could not be accomplished, aggressively increased

engin

torque to 98% and initiated a go around

From the UFDR it was evident that as long as the autopilot was engaged automati

ruddertrim was used to compensate for asymmetric power

. However the ruddertrim i

inherently slow and does not compensate immediately for fast power changes

. The UFD

shows that the Captain applied little or no rudder to compensate for the lagging trim

Instead he corrected the resulting roll exclusively with ailerons

. From the moment th

autopilot was disengaged rudder deflection was kept roughly in the same position, eve

during substantial powerchanges and neutralizing the trim

It must be concluded that throughout the entire approach the aircraft never stabilized i

power, airspeed and pitch which in all probability was caused by a lack of awareness o

the Captain with the existing situation, i

. one engine in flight idle instead of feathere

with consequently a higher drag and higher asymmetrical forces

. Insufficient use o

rudder resulted in the displacement of the aircraft to the right of the runway

2.3

.3 Go Aroun

During the go around manoeuvre again no additional rudder was used to compensate fo

the high asymmetrical power

. The resulting roll was counteracted only with ailerons an

the aircraft continued to roll to the right

. As the pitch was substantially increased durin

the go around IAS further dropped and the bank angle to the right increased

At 12

:45

:58 the bank angle reached 12° with a pitch of +12° and an IAS of 103 knot

and the stall warning was activated . Some additional rudder was applied

. Pitch was

reduced to +6° but immediately increased again to +9° at 12

:46 :03

. Combined with

reduced IAS of 96 knots and a bank angle of 30° the stall warning was activated for th

second time

. Only at this moment full left rudder was applied

. As a result of the low IA

and the large bank angle control of the aircraft could not be regained

The only viable option for the flightcrew at this stage would have been a power increas

on the

engine

. Apparently the use of the

engine was mentally blocked

.4 Crew Resource Managemen

Crew Resource Management (CRM) is the effective use of all resources available to th

flightcrew, including equipment, technical/procedural skills, and the contributions o

crewmembers and others

Situational awareness is the continuous extraction of information from a system o

environment, the integration of this information with previous knowledge to form

coherent mental picture and the use of that picture in directing further perception

anticipating and responding to future events

Effective communication between crewmembers is essential to share this information, t

direct actions and to share what one is thinking

The transcript of the CVR is the main source for the assessment of CRM, communicatio

and situational awareness in this analysis

The following examples of flightcrew behaviour are indicative for the lack of explicit an

efficient communication, situational awareness and CRM skills

After the engine oil pressure low warning the flightcrew used the ECL to diagnose th

situation

. The Captain, at the end of the checklistprocedure, came to the right conclusion

"Continue normal operation"

. The engine power, however was not restored

. Althoug

there was time available, the flightcrew did not thoroughly discuss the consequences o

the aircraft configuration for the remainder of the flight, nor did they consult th

AOM/Dispatch Deficiency Guide

. The Captain merely declared not to proceed to Cardif

and to return to Amsterdam . According to a statement of the chief-instructor of the SAA

340 division, he and the Captain (at that time FO) had experienced a similar situatio

(engine oil pressure low warning) during which the situation was thoroughly discussed

and then the decision was made to use both engines in case of a go around

The Captain chose, without any discussion with the F0, runway 06 for landing

. He di

not ask for the wind . At first contact with ATC/Arrival a wind of 250° with 10 knots wa

reported

. The F0 informed the Captain of a 10 knots tailwind (the maximum allowabl

tailwindcomponent is 10 knots), again without any discussion

Although the aircraft was in an abnormal configuration (one engine at flight idle power)

during the execution of the descent checklist the Captain accepted without any discussio

the suggestion of the F0 to use the abbreviated procedure

: "Standard zero six"

By not taking into account the configuration of the aircraft and the environmental factor

the Captain did not show good situational awareness

. The lack of explicit and effectiv

communication between the Captain and the F0 contributed to this lack of situationa

awareness

The F0 communicated most of the time in a non-assertive way

. His statements an

remarks showed at times good insight but were mainly presented as suggestions, no

challenging the Captain to behave in a more proactive way

The lack of Crew Resource Management skills, poor communication and lack o

situational awareness played an essential role in the chain

of events leading to th

accident

CRM is legally not yet required

KLC was in the process of developing Crew Management Courses (CMC-1 and CMC-2)

CMC-1 had been introduced

; the Captain had followed this course and the F0 wa

scheduled for it

. CMC-2 was not yet available

According to statements of KLC flight instructors and the head of KLC flight operation

however, the Captain had sufficient knowledge and experience to be able to handle a

emergency as occurred

.5 KLC Pilot Selection and Trainin

KLC's selection criteria and training program are well above minimum legal require-

ments

The analysis of the Captain's training history revealed that he experienced n-1 problem

during type rating

. These problems were at that time corrected by additional training an

re-examination

. He passed his type rating examination at 16 April 1992 and started flyin

as F0 with KLC

From that moment until the time that he was found eligible to start the Captain's trainin

the only occasion to assess his n-1 performance was the Simulator Proficiency Check o

25 November 1992

. Although this check was assessed as proficient, remarks indicate

that he again experienced n-1 problems and had been assessed "Standard Minus" on thi

subject

At 27 September 1993 he started the Captain's training

. No further n-1 problems occurre

and on 17 November 1993 he was promoted to Captain

The Board realises that in general, proficiency check performance reflects a momentar

observation and that a candidate should be given the opportunity to rectify a "Belo

Standard" and multiple "Standard Minus" performance during a re-examination or b

additional training

. The Board is however of the opinion that recurrent problems in

specific area of operation should not be addressed merely by additional training and re

examination

A selection and training program should be organized in such a way that problems of thi

nature are recognized as potentially structural and in that case should be solved in othe

and more reliable ways

.6 Single Engine Performance SAAB 340

When the go around was initiated the actual speed (110 knots) was higher than th

minimum control speed (103 knots) and with the proper flight technique the aircraft coul

have been kept under control

Performance calculations showed that in the configuration with flaps 7° and landing gea

up, the available climb gradient of 2 .3% should have made a go around possible

Procedure

The flightcrew had to operate the aircraft with procedures and instructions as laid down i

the

KLM

Cityhopper

SAAB 340B AOM

. Relevant paragraphs were checked an

compared to the AOM issued by the manufacturer

. The Board considers the foun

differences not directly contributing to the accident

. However several procedures stated i

the

KLM

Cityhopper

AOM were either unclear or not complete

Engine

Prop Oil Pressure Low Procedure

One oil low pressure warning light is used both for engine and propeller low oil pressure

The ECL procedure asks for a crosscheck of the engine oil and propeller oil indicators t

validate the warning

. The subsequent engine oil pressure low ECL procedure is clear an

complete

If however the propeller oil pressure low ECL procedure is applicable and the propelle

oil pressure is between 5 and 25 psi then the power lever has to be placed in flight idl

and the condition lever in minimum, resulting in a flight condition similar to fligh

KL433

. Neither SAAB nor KLC ECL does give further guidance whether a flight in thi

case should use

OEI

or AEO procedures

.7.2

Ruddertrim Procedur

On short final at approximately 230 feet the ruddertrim was neutralized, which actio

contributed to the developing lateral instability

In the SAAB 340B manufacturer's AOM it is advised to center the yaw trim ("trim zero"

)

prior to the landing flare . No information regarding trimming during (manual) 0E

operations is provided in the KLC

SAAB 340B AOM

It is understood from interviews with KLC SAAB 340B instructors that pilots are traine

to use autoflight as long as possible, taking the benefit of rudder trimming by th

autopilot

. There is no common procedure for neutralizing the trim after autopilo

disengagement

Approach Speed

In the AOM a procedure should be given how to determine approach speeds in norma

and abnormal conditions

. This determination should be clear and unambiguous

In general the final approach speed should be maintained until approaching the threshol

before reducing to

This Vru should be increased with a wind correction, if applica-

ble a malfunction correction should be applied, and a maximum stated

. The minimu

final approach speed is Vru + a defined increment (e

. 10 knots)

In the

KLM

Cityhopper

AOM

The approach speed determination for all conditions is not always clear

;

the correction for moderate windspeeds is insufficient

;

the prescribed approach speed below 300 feet is

potentially

unsafe as the increment t

is deleted in Visual Meteorological Conditions (VMC) leaving no margin for lo

level wind change, turbulence or performance decreasing windshear

.8 Flight Safet

2.8

.1 Cabin/Passengers Preparatio n

The

"No

Smoking and Fasten Seatbelt"

signs were switched on well before the acciden

and all the passengers were properly strapped in

. However, due to the early arrival, cabi

service was not finished

. Since a normal landing was expected to take place, no specia

warnings or briefings were necessary

2.8

.2 Survivabilit

Survivability was conditioned by the absence of fire in the main wreckage

. Generally th

impact forces were not extreme

. The fatal injuries to the two passengers resulted fro

direct contact with damaged parts of the fuselage during the main impact

. However, du

to the lateral direction of the impact forces, a number of passengers were seriousl

injured

As a result of the deformation of the center fuselage and the consequent release of a smal

number of seats in that area, evacuation and rescue were hampered

. Also the position o

the fuselage, lying on its

side, hampered evacuation and rescue, as the

exits wer

not accessible and the

exits were difficult to reach

. In case of cabin fire this woul

have been fatal

.9 Air Traffic Contro

ATC handled the emergency efficiently, offering a choice of two runways for landing

Consideration was given to possible controllability problems and the aircraft was vectore

without delay for an

ILS

approach runway 06

. Frequency changes were minimal

.10 Fire Fighting

Rescue Service

Fire fighting and rescue operations were conducted efficiently

. The decision not to ente

the soft terrain with the heavy fire fighting vehicles was a prudent one, and, in view o

the absence of fire in the main wreckage, it is considered correct

The malfunction of the Airside emergency communication system did not affect th

communication between the units at the scene of the accident

. The evaluation of the fir

fighting and rescue actions by Airside Operations revealed a number of shortcomings

The Board is of the opinion that these shortcomings did not influence the outcome of th

fire fighting and rescue actions

CONCLUSION



The flightcrew was licensed, qualified and certified to operate the aircraft



3.2



Meteorological conditions were on itself not a factor in this accident



Prior to the flight the aircraft was fully serviceable

Weight and balance were within limits



During climb the

engine oil pressure switch failed, resulting in aural an

visual warnings in the cockpit



In a reaction to the oil pressure warning the Captain slowly retarded the right han

power lever to flight idle

The flightcrew did not realise that the decrease of the

engine oil pressure wa

the result of the power reduction

Although the oil pressure remained within normal operating limits they - contrar

to ECL procedures - kept the

engine running in flight idle

The Captain did not realise the consequences of flying with one engine in fligh

idle and was not able to anticipate correctly on the airspeed variations whic

resulted in an approach not stabilized in power, airspeed and pitch during the fina

approach

. A situation which was possibly aggravated by the tailwind component

Neither the manufacturer

AOM

nor the KLC's

AOM of

the

SAAB 340B

contain

guidance material concerning the consequences

an engine in flight idle

While actually using only one engine the return flight and approach were execute

using

All

Engine Operative procedures

3 .10

Incorrect use

rudder resulted in a displacement

the aircraft to a position righ

the runway, from which a landing was not feasible and a go around wa

initiated

.11

During the go around inadequate use of the flight controls by the Captain resulte

in loss of control

.12

Crew Resource Management during the flight was virtually non-existent

.13

Performance calculations showed that under the prevailing circumstances, with on

engine in flight idle, using proper flight techniques, a go around could have bee

made

.14

Except for the failed engine oil pressure switch there was no evidence

any othe

failure or defect on the aircraft, including engines and systems

.15 The accident can be classified as generally survivable

. Failure to utilize availabl

restraint provisions (shoulder straps) in the cockpit resulted in a fatal injury

.16 The concept of KLC's Pilot Selection and Training is above legal requirements

The current assessment techniques did not allow the recognition of the nature o

the n-1 problems of the Captain as possibly structural

.17 Several procedures in the KLC AOMIECL for the Saab 340B were either unclea

or not complete

- Engine and Prop oil pressure low procedure

;

determination of approach speeds

;

neutralizing of rudder trim during One Engine Inoperativ

approach/landing phase

.18 ATC, fire fighting and rescue services handled the emergency and the accident i

a proficient way

. The fact that NVLS fire fighting and rescue vehicles did no

traverse non-stabilized agricultural terrain did not influence the survivabilit

aspects

4 PROBABLE CAUSE

Inadequate use of the flight controls during an asymmetric go around resulting in loss o

control

Contributing Factor

Insufficient understanding of the flightcrew of the SAAB 340B engine oil system

Lack of awareness of the consequences of an aircraft configuration with one engine i

flight idle

Poor Crew Resource Management

5 RECOMMENDATION



Evaluate and improve where necessary the current assessment techniques

.2 Establish a Crew Resource Management training and integrate CRM into Com-

mand Promotion Assessment

.3 Evaluate/improve KLC SAAB 340B AOM/ECL information to contain guidanc

Use/prohibition of engine flight idle operation

;

neutralizing ruddertrim during One Engine Inoperative approach/landing phase

.4 Review the procedure in the KLC AOM how to determine correct approac

speeds



5.5



Evaluate/improve capability of fire fighting and rescue vehicles to traverse non

stabilized terrain

APPENDIX

PHOTOGRAPH

The aircraft during the go aroun

Wreckage distribution

APPENDIX

UNIVERSAL FLIGHT DATA RECORDE

READOUTS

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