File N0.A-0001 - Online Collectionslibraryonline.erau.edu/online-full-text/ntsb/aircraft-accident-reports/... · File N0.A-0001 AIRCRAFT ACCIDENT REPORT Jugoslovenski Aerotransport

File N0.A-0001

AIRCRAFT ACCIDENT REPORT Jugoslovenski Aerotransport [JAT)

Boeing 707-321, YU-AGA John F. Kennedy International Airport

Jamaica, New York August 13, 1972

Adopted: April 4, 1973

NATIONAL TRANSPORTATION SAFETY BOAR0 Washington, D.C. 20591

REPORT NUMBER: NTSB-AAR-73-7

. Report No. I 2.Government Accession No. TECHNIC

NTSB-AAR-73-7 . Ti t le and Subtitle Jugoslovenski Aerotransport :JAT) Boeinx 707-321, YU-AGA. John F. ~~~~~d~ - [nternational Airport, Jamaica, New York,

. Author(s)

~ ~I

4ugust 13, 1972

8 . Performing Organization Name and Address National Transportation Safety Board Bureau of Aviation Safety Washington, D. C. 20591

2.Sponsoring Agency Name and Address

NATIONAL TRANSPORTATION SAFETY BOARD Washington, D. C . 20591

L REPORT STANDARD T I T L E PAGE 3.Recipient's Catalog No.

5.Report Date

6.Perforrnina Oraanization April 4 , 1973

Code - -

8.Performing Organization Report No.

10.Work U n i t No. 1058

11.Contract or Grant No.

13.Type of Report and Period Covered

Aircraft Accident Report August 13, 1972

14.Sponsoring Agency Code

5.Supplementary Notes

l6.Abstract On August 13, 1972, at 0050 eastern daylight t ime, while aborting a takeoff f r o m Runway 13R, John F. Kennedy International Airport, Jamaica, New York, Jugoslovenski Aerotransport (JAT) Flight 3410 ran off the end of the runway.

There were 175 passengers and a crew of 11 aboard the a i rc raf t a t the t ime of the accident; 15 passengers and a steward were injured during evacuation.

During the takeoff, the right cockpit sliding window came open, and made a loud noise. The captain initiated action to reject the takeoff. The a i rc raf t ran off the end of the runway, struck the blast fence, and came to a stop approximately 120 feet f rom the end of the paved surface and 8 0 feet to the right of the runway.

f i re . The crew and passengers successfully evacuated the a i rc raf t by means of the The left wing and engines Nos. 1 and 2 were damaged by impact and the ensuing

emergency slides.

of this accident was the unknown degraded capability of the heavily loaded air- The National Transportation Safety Board determines that the probable cause

craf t ' s braking system, which precluded stopping the aircraf t within the runway distance available. the reduced braking capability resulted f rom a malfunctioning V-3 relay in the left antiskid control shield of the a i r c ra f t ' s braking system, which rendered two of the eight-wheel brakes ineffective. A sound like that of an explosion in the cockpit during the takeoff rol l caused the captain to reject the takeoff,

17. Key Words 18.Distribution Statement Aircraf t accident, Aborted takeoff, Antiskid system Wheel brakes, F i r e damage, Faulty V-3 relay,

configuration distribution unlimited. 8-wheel brake configuration, 6-wheel brake Release to public;

19.Security classif icat ion 22.Price 21.No. of Pages 20.Security Classification (of this reoort) (of this oaae) .~ ~ ~

UNCLASSIFIED NTSB Form 1765.2 (11/70)

~r~ ~. .~ ~ ~ < ~ .

URCLASSIFIEO 1 29 I i i

1 . 1.1 1 . 2 1 . 3 1 .4 1 .5 1 .6 1 . 7 1 .8 1 .9 1 .10 1 .11 1.12 1 . 13 1 . 14 1 . 15 2 . 2.1 2.2

3 .

JUGOSLOVENSKI AEROTRANSPORT ( JAT) BOEING 707.321. YU-AGA

JOHN F . KENNEDY INTERNATIONAL AIRPORT JAMAICA. N E W YORK

AUGUST 13. 1972

TABLE OF CONTENTS

Page

Synopsis ....................................... History of the Flight Investigation

Injuries t o P e r s o n s .............................. Damage t o Aircraf t .............................. Other Damage .................................. Crew Information ............................... Aircraf t Information ............................. Meteorological Information ....................... Aids t o Navigation ............................... Communications ................................. Aerodrome and Ground Faci l i t ies ................. Flight Recorders ................................ Wreckage ...................................... Fire ........................................... Surviva lAspects ................................ T e s t a n d R e s e a r c h .............................. Analysis and Conclusions ........................ Analysis ......................................

................................... ............................

.elusions.................................... Findings ................................... Probable Cause ............................ 20

Recommendations ............................... 21

Appendix A Investigation and Hearing . . . . . . 2 2 Appendix B Crew Information . . . . . . . . . . . . . 23

Appendix D Airport Diagram . . . . . . . . . . . . . . 2 7

Appendices

Appendix C Aircraf t History . . . . . . . . . . . . . . . 26

iii

1 2 2 4 5 5 5

6 5

7 7 7 7 8 9 9

10 13 13 18 18

File No. A-0001

NATIONAL TRANSPORTATION SAFETY BOARD WASHINGTON, D. C. 20591

AIRCRAFT ACCIDENT REPORT

Adopted: April 4, 1973

JUGOSLOVENSKI AEROTRANSPORT (JAT) BOEING 707-321, YU-AGA

JOHN F. KENNEDY INTERNATIONAL AIRPORT JAMAICA, N E W YORK

AUGUST 13, 1972

SYNOPSIS

Jugoslovenski Aerotransport ( JAT) Flight 3410 was involved in an accident on August 13, 1972, at 0050 ea s t e rn daylight t i m e during a rejected takeoff f r o m Runway 13R a t the John F. Kennedy International Airport , Jamaica, New York. The re were 175 passengers and a c r e w of 11 aboard the aircraft at the t ime of the accident; 15 passengers and a steward were injured during the evacuation f r o m the a i rc ra f t .

During the takeoff, the right cockpit sliding windown came open, which made a loud noise. This action occur red 3 seconds a f t e r the cocaptain had called V I . The captain initiated action t o re jec t the takeoff. The a i rc ra f t r a n off the end of the runway, s t ruck the blast fence, and came to a stop approximately 120 feet f r o m the end of the paved sur face and 80 feet t o the right of the runway. The left wing and engines Nos. 1 and 2 were damaged by impact and the ensuing fire. The c rew and passengers successfully exited the a i rc ra f t .

The emergency equipment f r o m the P o r t of New York and New Jersey Authority a r r i ved on the scene in approximately 4 minutes and extinguished the f lames.

The National Transportation Safety Board determines that the probable cause of th is accident was the unknown degraded capability of the heavily loaded a i r c r a f t ' s braking sys tem, which precluded stopping the a i rc ra f t within the runway distance available. The reduced braking capability resulted f r o m a malfunctioning V-3 re lay in the left antiskid control shield of the a i r c r a f t ' s braking system, which rendered two of the eight-wheel b rakes ineffective. A sound like that of an explosion in the cockpit during the takeoff roll caused the captain t o re ject the takeoff.

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1. INVESTIGATION

1. 1 History of the Flight

Jugoslovenski Aerotransport (JAT), a Boeing 707-321, YU-AGA, operating a s Flight 3410 (JU3410) on August 13, 1972, was scheduled f r o m the John F. Kennedy ( J F K ) International Airport t o the Rijeka Airport , Rijeka, Yugoslavia.

JU3410 was an international operation transport ing a cha r t e r group of 175 passengers f r o m the United States t o the Island of Krk on the Northern Adriat ic Sea Coast of Yugoslavia and was scheduled for depar ture at 23301/3 August 12, 1972. The actual depar tu re f r o m the Bri t i sh Overseas Airways Corporation (BOAC) te rmina l gate was at 0023:45.

The aircraft r an off the end of the 14,572-foot Runway 13R and impacted the blas t fence at the end of the runway during an attempt t o reject the takeoff.

An International Instrument Flight Rules f l ight plan was filed for JU3410 by the P a n American World Airways (PAA) New York dispatch office f r o m J F K to Shannon, Ireland. This dispatching was done under contract ar rangements between PAA and JAT. The c r ew ' s stated in- tention was t o ref i le in-flight over Shannon fo r Rijeka o r an a l ternate , depending on weather conditions.

The flight dispatch re lease fo r JU3410 of August 13, 1972, was prepared and signed by the PAA dispatcher on duty. The dispatch re- l ease was valid until 0030. However, in o rder fo r such a r e l ea se t o be in effect, it was necessa ry for the captain of the flight tq sign, indicating that he concurred with the dispatcher that the contemplated operation could be safely conducted under the prevailing and forecas t conditions. The captain did not sign the dispatch r e l ea se f o r JU3410 of August 13, 1972.

The c rew prepared a Yugoslav Airl ines loadsheet at the BOAC Termina l and increased the fuel loading indicated on the PAA dispatch

1/ All t imes here in a r e eas te rn daylight, based on the 24-hour clock. ~~~~~ ~~ ~ ~ ~

-

- 3 -

re lease f r o m 108, 900 pounds to 137, 000 pounds. This fuel, l e s s 2 , 000 pounds necessary for taxi, placed the calculated g r o s s weight of the a i r - craft a t i ts maximum s t ructura l weight limit of 312, 000 pounds f o r this takeoff. The PAA Dispatcher was not informed of these changes.

Upon boarding the a i r c ra f t , and during the cockpit check of the a i rcraf t , the c rew listened to the ATIS ?I "Zulu, " effective at 2251, August 12, 1972, which announced, among other a i rpor t data, that the wind was 220' (magnetic) at 8 knots. Neither the J F K Tower Ground Controller nor the J F K Local Controller volunteered any information that the wind was other than a s had been given in the effective ATIS broadcast. The actual wind, a s recorded by the National Weather Service at 0051, August 13, 1972, was 220° T r u e (210° magnetic) at 8 knots.

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BOAC, a lso working under contract with JAT, performed the a i r - craft preparat ion ( i . e . , fueling, maintenance re lease , required r a m p maintenance, a i rcraf t loading, e t c . , a s well a s passenger handling) f o r the flight.

The c rew calculated the a i rcraf t total weight at the beginning of the takeoff t o be 311,725 pounds. The takeoff reference speeds ( V speeds)^ 21 for an a i rc ra f t of this weight with a t empera tu re of 71°F. (21OC. ) would be:

V1 - 150 knots

VR - 160 knots

Vz - 170 knots

These speeds were obtained f r o m the a i r c r a f t ' s operating manual and were placed on the takeoff data card by the flight engineer.

At 0015:20, the cocaptain f o r the flight, who was occupying the right seat and who was performing the duties of the copilot, called the J F K Clearance Delivery Controller f o r the flight clearance.

- 2 1 ATIS - Automatic Terminal Information Service.

21 V Speeds - V I - cr i t ica l engine fa i lure speed. VR - rotation speed.

V2 - takeoff safety speed.

- 4 -

At 0020:00, the cocaptain called J F K Ground Control for pushback f r o m the BOAC Termina l and asked for taxi c learance t o Runway 13R. Runway 22R was in use at this t ime; however, JU3410, at the existing g r o s s weight and the existing t empera tu re , would have been at the maximum limit f o r a takeoff f r o m the 11, 350-foot Runway 22R. The c r e w requested the use of the 14, 572-foot Runway 13R. Th i s request was granted and the flight was cleared t o taxi t o Runway 13R at 0026.

At 0047:50, JU3410 was cleared into position to hold on Runway 13R and at 0049:05, the flight was c leared f o r takeoff.

As the a i rc ra f t accelerated, the cocaptain called 80 knots a i rspeed, followed 2 5 seconds la ter by the V1 call . Three seconds af ter the V1 call , the right cockpit sliding window opened, and crea ted a loud noise.

The captain immediately initiated the re jec t takeoff procedures , deployed speed brakes , selected reverse th rus t , and placed 100 percent N 1 2 / on a l l four engines, and then applied the main wheel b rakes . The a i rc ra f t continued along the runway and left t i r e skid marks f o r about the las t 1 . 2 statute mi le ( s e e Appendix D) . Near the intersect ion of Runway 13R and 4L, the skid m a r k s a r c e d slowly f r o m as t r ide the centerl ine to the right s ide of the runway. The a i rc ra f t r a n off the right s ide of the paved surface at the end of the runway. The a i rc ra f t then continued through the blast fence to a point 120 feet f r o m the end and 80 feet t o the right of the runway. The a i rc ra f t c a m e t o a stop with the left outboard wing section engulfed in f lames. The engines were shut down, and the f i r e extinguishing sys tems were activated for the N o s . 1 and 2 engines. The captain exited f r o m the a i rc ra f t through the cockpit left sliding window to keep the passengers away f r o m the f i r e and to expedite the i r movement away f r o m the burning a i rc ra f t . The other flight c rewmembers went t o the passenger cabin t o a s s i s t in passenger evacuation.

1 . 2 Injuries t o P e r s o n s

Injuries Crew Passengers Other

Fa ta l 0 0 0

Nonfatal 1 1 5 0

None 10 160

- 41 N1 - engine low-pressure turbine speed.

e

:rs

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1 . 3 Damage t o Aircraft

The nose cowl sections of the Nos. 1 and 2 engines and the outboard section of the left wing received major damage in impacting the blast fence, and the left wing, outboard of the No. 2 engine was damaged by f i re . The front and r e a r t i r e s on the N o s . 2, 3, and 4 tandem wheels - 51 were flat and a l l but one t i r e contained evidence of even wear. A l l of the t i r e s had t r ead remaining on the c a r c a s s e s , and only the No. 3 rear t i r e had a "flat" spot worn into the cords of the t i r e body.

1 . 4 Other Damage

Thir ty feet of the s t ee l blast fence at the end of Runway 13R/31L was destroyed. Several frangible fittings, located about midway up the support brackets of the blast fence s t ruc tu re were separa ted by the impact.

1. 5 Crew Information

The c rewmembers were certificated in accordance with existing Yugoslavian regulations and International Civil Aviation Organization (ICAO) standards to p e r f o r m the duties of flight c rewmembers for this flight. (See Appendix B f o r details. )

1. 6 Aircraft Information

Aircraft YU-AGA, A boeing 707-321, s e r i a l No. 17601 was leased by the Jugoslovenski Aerotransport ( JAT) f r o m the GATX Bulk C a r r i e r Number Three of Monrovia, Liberia . The a i rc ra f t fo rmer ly had been owned and operated by P A A under United States Regis t ry N723PA. At the t ime of the accident, the a i r c ra f t was reg i s t e red in Yugoslavia. (See Appendix C for detai ls . )

The a i rc ra f t cabin configuration had 177 passenger sea ts and four cabin crewmember jump sea t s .

The maximum design takeoff g r o s s weight was 312, 000 pounds. The center of gravity l imits for the loading of this a i r c r a f t in a passenger configuration were 21 percent forward and 35 percent aft

- 5 / The main landing gear consists of eight wheels that a r e ar ranged in a tandem s e r i e s and a r e numbered from left to right.

- 6 -

Mean Aerodynamic Chord (MAC). The stabi l izer t r i m was se t at "21" during completion of the pretakeoff checklist. The t r i m setting was found at 22 percent MAC af ter the accident.

A l l baggage and s p a r e p a r t s were weighed af ter the accident. These weights, passenger normal weights, plus other operational weights (fuel, oil, c rewmembers , etc. ) combined to a calculated g r o s s weight of about 311, 000 pounds at the t i m e the b rakes w e r e r e - leased to commence the takeoff.

1. 7 Meteorological Information

JU3410 had been provided with meteorological data pertinent t o the PAA computer flight plan to Shannon, Ireland, with an a l te rnate of Heathrow Airport , London, England. No weather information was provided by PAA to the c rew for the continuation of the flight f r o m Shannon, Ireland, to Rijeka, Yugoslavia.

The crew, af ter boarding the a i rcraf t , received the Kennedy Airport Terminal Information Service, as follows:

"This is Kennedy Departure Information Service with Information Z U L U . Departure Runway 22R. Wind 220' 6_/ at 8. Altimeter 30. 08. Tempera tu re 71° a t 0251 Z . "

ATIS information was the only local weather provided t o the c rew af ter they had boarded the a i r c ra f t .

The National Weather Service 0051 local weather observation was in par t :

Ceiling measured 4,600 feet broken, 25, 000 broken, visibility 8 mi les , temperature 71° F . , dewpoint 62O F . , wind 220' 7/ 8 knots, a l t imeter setting 30. 08 inches.

- 61 Wind is reported by magnetic direction by tower personnel.

- 71 Wind was recorded by t r u e direction by weather obse rvers . The magnetic variation for the J F K a r e a was l o o W.

.

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1. 8

1 . 9

The local weather observation taken at 0101 was:

Ceiling measured 4 ,600 broken, 25, 000 broken, visibility 8 miles , t empera ture 70' F . , dewpoint 62O F. , wind 220°, 7 knots, altimeter 30. 08, r emarks - aircraft accident.

Aids t o Navigation

Not involved.

Communications

No difficulties with communications between the flight and the air traffic control faci l i t ies were reported.

1.10 Aerodrome and Ground Faci l i t ies

Runway 13R/31L a t the John F. Kennedy International Airpor t is 14,572 feet long and 150 feet wide. The runway is constructed of con- c re te and has a Fede ra l AviationAdministration (FAA) g ros s weight strength limitation of 340, 000 pounds f o r an a i r c r a f t with dual wheel tandem design. The sur face of the runway contains numerous repa i r patches of an asphalt ic mater ia l . The runway profi le of 13R is undulating .

Steel blast fences were l is ted on the FAA Airport Master Record dated September 21, 1970, at 13R/31L; however, the only blast fence on this runway i s at the end of Runway 31L.

Runway 13R was equipped with high-intensity runway lights that were controlled by a f ive-step intensity se lec tor switch in the tower. The lights were set on "Step 1" which was the lowest intensity setting. A l l runway lights were operating at the t ime of the accident.

1 .11 Flight Recorders

YU-AGA was equipped with a Lockheed Aircraf t Service Co., Model 109-C Flight Data Recorder (FDR) and it was operatinx.

The altitude t r a c e was constant and consistent with the runway elevation.

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The airspeed t r a c e showed an increasing a i rspeed f r o m the t i m e of brake re lease f o r a period of 54 seconds, attaining a maximum of 154 knots. The speed was then relatively constant fo r 3 seconds, followed by a constant r a t e of decline f o r 18 seconds, down to 70 knots. There were e r r a t i c excursions of the a i rspeed t r a c e during the ensuing 3 seconds down to a speed of 34 knots, a s traight- l ine excursion f o r 4 seconds, and a dec rease in speed to 32 knots in the next 2 seconds. The t r a c e then resumed approximately the s a m e r a t e of dec rease that was shown f r o m 154 knots down t o 70 knots and continued t o d e c r e a s e to about 10 knots; the r a t e of dec rease then flattened and the speed de- c reased from 10 knots t o 8 knots in 4 seconds.

The a i rcraf t was a lso equipped with a Fairchild Model A-100 Cock- pit Voice Recorder . The unit and the tapes were undamaged by the accident, and a t ranscript ion of the voices and sounds, commencing at the t i m e of the c rew ' s initial cal l to the J F K Tower, was made.

The tape disclosed that at 0049:05.5, JU3410 was c leared f o r takeoff and at 0049:26. 5, the captain stated, "Let ' s go. " The cocaptain, 23. 7 seconds la ter , called 8 0 knots, and 24. 03 seconds l a t e r , the V I . Three seconds af ter the V1 cal l , the noise of an explosion, followed by a continuing r o a r , was recorded. During the next 43 seconds, until the a i rcraf t came to a stop, the following comments were recorded sequentially: "Window open . . . engine down . . . speed b rakes . . . reverse . . . al l r eve rse . "

1. 12 Wreckage

The a i rc ra f t sustained extensive damage t o the left outboard wing panel, left a i leron, and the left outboard wing flap a s the resul t of impact with the s t ee l blast fence and the ensuing f i re .

The nose cowl sections of the N o s . 1 and 2 engines were crushed rearward t o the compressor fan inlet a r e a of the engines.

The lower wingskin between the No. 2 engine and the No. 1 engine was severe ly damaged by impact.

The Nos . 2 , 3, and 4 front and r e a r brakes had been subjected t o extremely high internal heat. The disc lugs f o r these b rakes had been sheared and pieces of the lugs were found in the wheel s lots . Numerous brake re tu rn springs were missing f r o m these b rakes ; severa l were found along the runway, about 1, 000 feet p r i o r to the end of 13R.

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1. 1 3 F i r e

A f i r e engulfed the left outer wing panel outboard of the No. 2 engine following impact of the a i r c ra f t with the blast fence. The left fuel tank was ruptured, and a ground f i r e developed f r o m the spilled fuel.

1.14 Survival Aspects

The a i rc ra f t came to a stop in the sand off the end and to the right of the runway. F i r e s s ta r ted in engines Nos. 1 and 2 , the left outboard wing section, and on the ground underneath the left wing.

F ive c rewmembers occupied the cockpit, and s i x cabin attendants were stationed in the cabin. The cabin attendants were stationed as follows: two on the aft-facing jumpseat by the forward ent ry door, two on the forward facing jumpseat at the aft entry door, and two in the f i r s t passenger sea t s on the left side of the a i rcraf t . P a s s e n g e r s occupied al l of the remaining sea t s in the cabin.

A predepar ture emergency briefing and information announcement was made by the No. 1 p u r s e r during the 26-minute taxi f r o m the boarding gate to the runway. The passengers described a bumpy takeoff roll , followed by a rough bumpy deceleration until the t ime the a i r c ra f t c a m e t o a stop. None of the passengers o r c rewmembers reported receiving any injury during this portion of the occurrence. All cabin s t ruc tu re and furnishings remained intact, but pi l lows and blankets fe l l f r o m the overhead s torage racks into the center ais le . Stacks of extra m e a l boxes, numerous canned drinks, a s well as ice f r o m ice buckets were propelled into the a i s l e s and galley a r e a s . These i tems had not been secured p r i o r to the takeoff. Severa l passengers reported that these loose objects impeded the i r exit f r o m the a i rc ra f t .

The passengers began to evacuate the cabin on the i r own initiative when they observed f lames outside the left side of the a i rc ra f t . No announcement was made over the public address sys t em o r the self- powered megaphones, even though this emergency equipment was available in the cabin.

The escape rope at the left sliding window of the cockpit, the inflatable slide at the forward entry door, and t h e slide a t the forward galley serv ice door were deployed and used during the evacuation of the a i rcraf t . The slide fo r the aft galley serv ice door was automatically deployed when the door was opened by the No. 4 s teward; however, the

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slide failed to inflate af te r he reportedly activated it. The steward and the aft pu r se r , followed by severa l passengers , jumped f r o m the aft galley exit to the ground. The distance f rom the floor to the ground was approximately 8 feet. A short t ime la te r , a f te r all passengers had exited, this slide was observed to be inflated and holding p res su re . Examination of this slide and its associated mechanisms af ter the accident did not disclose a discrepancy o r malfunction of any component, and the re was no explanation of the fai lure of the s l ide to inflate initially.

Several passengers evacuated through both overwing exists on the right s ide of the a i rcraf t . No cabin crewmembers were at these exists and the escape rope was not deployed. Passengers reported that they jumped f rom the t rai l ing edge of the wing, a distance of approximately 5 feet , and f rom the leading edge of the wing, which was approximately 7 feet above the ground. Eleven passengers and one s tewardess r e- ported that they received spra ins , s t ra ins , and bru ises of the extremit ies a s a resul t of jumping to the ground f r o m the right wing o r the aft galley exit. No ser ious injuries were sustained by c rewmembers o r passengers a s a resul t of the accident o r a s they disembarked f r o m the a i rc ra f t .

The s i t e where the a i rcraf t came to a stop i s located 1 . 8 s tatute miles f rom the J F K No. 1 Airport F i r e Station and 1. 9 statute mi les f rom the JFK Satellite Airport F i r e Station.

The a i rpor t c r a s h alarm was sounded by FAA Tower personnel at 0050 and the a i rpor t emergency equipment was reported to have ar r ived at the burning a i r c ra f t at 0054. Al l occupants were out of the a i rcraf t p r i o r to the a r r i v a l of this emergency equipment. The f i r e was extinguished within 5 minutes af ter the a r r i v a l of the emergency equipment, with a minimal amount of f i r e damage to the a i rc ra f t .

1. 15 Tes t and Research

The copilot 's No , 2 sliding window came open 3 seconds af ter the a i rcraf t had accelerated to V I . The ro l l pin which secu res the window handle to i ts shaft was found withdrawn approximately a quar te r of an inch. The t r igger lock bolt had evidence of wear on the bottom end; the window adjusting rod was out of adjustment, shortened by one ful l tu rn of the rod; and the window handle machanism had excessive play in it. The window was checked fo r operation. (The normal f o r c e r e - quired to place the handle in the locked position is 45 t 15 pounds. ) A force of 48 to 60 pounds was required to close and lock the window. The spring-loaded t r igger in the handle hung in a midtravel position,

-

.

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and the associated t r igger lockbolt did not fully engage the lockplate hole. In this condition, the window would appear to be in the closed and locked position; however, any p r e s su re .on o r movement of the handle would disengage the t r igger lockbolt f r o m the lockplate and the window could open.

After the accident, a pencil, f rac tured in severa l places, was found in the window t rack. Comparison tes t s were performed by inserting a pencil in the handle t r igger lockplate and cover assembly hold adjacent t o the handle. The window ,was then unlocked and opened. The pencil sheared in the s a m e manner a s the one initially found in the window t rack . This t es t was performed twice with the s a m e resu l t s .

The brake-adjusting units were removed f r o m the b rake assemblies and checked fo r thei r flinctional capabilities. The units for the No. 2 forward and the No. 3 aft brake assembl ies were found to have a slight hydraulic leak at high p r e s su re s . A l l other units were found to be normal in all aspects .

A rotation check of the flywheel detectors in the b rake antiskid system bekween 500 and 1500 r . p. m. indicated a brake re lease condition on the No. 1 and the No. 4 forward and aft cockpit indicators. A l l of the detectors were removed and functionally tested with the following results:

Position

No. 1 Forward

No. 1 Aft

Test Speed

800 r. p. m.

1, 000 r. p. m.

Findings

Checked within specified l imits

High skid switch res i s tance between P ins C- D

Unit Clockwise Rotation

Limits Findings

. 9 4 - 1. 37 sec s . 1.48 sec s .

1. 18 - 1. 7 2 sec s . 1. 76 s ec s .

Unit Counterclockwise Rotation

500 r. p. m. . 59 - . 8 6 s ec s . . 9 l secs

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

No. 2 Forward Slightly high-skid switch res is tance between pins C-D and pins A-D

No. 2 Aft Clockwise, clutch tes t indicated skid switch signal t ime in excess of limits

No. 2 R e a r Unit .Clockwise Rotation

Tes t Speed Limits Findings

500 r. p. m. . 5 9 - . 86 secs . . 90 secs .

800 r. p. m. .94 -1.37 secs . 1.46 secs .

________________________________________-----------. -------------

No. 3 Forward P in s C-D and C-B closed c i rcui t ; unit inoperative when rotated clockwise.

No. 3 Aft Skid-deceleration r a t e slow

No. 3 Rear Deceleration Limits Findings

40 - 56 Radians 36 Radians

____________. _______--------------------------. ------------------

No. 4 Forward Checked within specified l imits

No. 4 Aft Clockwise, clutch t e s t indicated skid signal t ime in excess of l imits

No. 4 R e a r Clockwise Rotation

Tes t Speed Limits Findings

500 r . p . m. . 5 9 - .86 s ec s . . 9 0 secs .

800 r. p. m. . 9 4 - 1. 3 7 sec s . 1.45 secs .

1, 000 r.p. m. 1. 18 - 1. 72 secs . 1.76 secs .

The brake sy s t em antiskid control shields were removed and functionally tested. The left control shield fo r the No. 1 forward and aft brakes had a defective "V-3" relay that pre.vented i t f r o m being energized. Under the circumstance.s, no ma t t e r how much p r e s s u r e was applied to the brake pedals, the No. 1 front and r e a r b rakes r e - mained in a re leased condition.

The Boeing Company provided the following brake performance data:

1.

2 .

Est imated energy fo r the s i x brakes working during the stop:

39.28 x 10 foot pounds p e r brake. This value 6

is based on Boeing es t imates of the maximum effort stopping capability with r eve r se th rus t r a the r than analysis of the flight r e co rde r data.

Maximum energy level t o which the b rakes have been demonstrated as determined by analysis of the cer t i f i - cation flight t e s t data:

38.7 x 10 foot pounds p e r brake. This is the 6

brake energy value upon which flight manual limitation is based.

The Boeing Company a lso stated that the effect of a l o o change in wind direction, with the result ing 2-knot downwind component, would result in a negligible inc rease in the acce le ra te / s top distances f o r the aircraft.

The PAA Route Manual fo r a B-707 on Runway 13R +t J F K shows a required maximum g ros s weight reduction of 5, 000 pounds (i. e. 307,000 V. 312,000) with a 2-knot tailwind at 2 l o C . , (71'F. ). Boeing data show that the reduction of 5, 000 pounds would be necessa ry only if the takeoff is limited by runway length. W i t h 14, 572 feet of runway available, no limitation on the a i rc ra f t was necessa ry .

2. ANALYSIS AND CONCLUSIONS

2. 1 Analysis

The actual destination of the flight was Rijeka, Yugoslavia. Because the PAA dispatch computer does not have Rijeka, Yugoslavia

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in i ts system, the a i rcraf t was dispatched to Shannon, Ireland. In this case , if the computer-predicted fuel consumption was accura te , the a i rcraf t would have been 20,000 pounds overweight on landing at Shannon. However, JAT company procedures allow - - depending upon the fuel remaining and the existing weather conditions - - the captain to refi le in the a i r , to another destination.

The complex servicing, maintenance, and dispatching procedures being handled through contract and subcontract methods tend to remove o r dilute the responsibility of the c a r r i e r for operations such a s a r e involved in this accident. F o r example, an organization which operates an a i rcraf t does not have the responsibility of t ime control on the components installed on the a i rcraf t . Moreover, recordkeeping, replace- ment of pa r t s , and maintenance of a l l types a r e taken c a r e of by contract. Contractual agreement a lso places the responsibility for the s p a r e p a r t s c a r r i e d aboard the a i rcraf t on other than the operator . Finally, this method of dispatching separa tes the operator and his method of flight operation f rom the direct line control and supervision of the dispatch function. Although these a r e a s of operational control and the observed weaknesses therein were not in the causal a r e a of this accident, they a r e discussed in order that this operator, and other opera tors , may be aware of the possible problems of such complex ar rangements .

The opening of the copilot's sliding window was the initiating factor in the captain's decision to reject the takeoff.

i

The condition of the locking mechanism in this window was such that a l l outward appearances convinced the cocaptain that his window was closed and locked. The facts , however, demonstrate that the locking mechanism was out of adjustment, the locking bolt t r igger was hanging up in a midposition, and the locking bolt was not fully in place in the lockplate hole.

i t i

Based upon the data obtained f rom the t e s t s with a pencial inserted in the cover assembly hole adjacent to the handle of the sliding window, the Board concludes that the pencil was not instrumental in preventing the window f rom being closed o r locked.

The roughness and undulation of the surface of Runway 13R, discussed by the c r e w ' while taxiing t o the runway, is considered to have been a factor in the opening of the cocaptain's window during the

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takeoff, since the roughness of the runway would have been t r ansmi t t ed to the a i r f r a m e while the a i rc ra f t was accelerat ing on the runway surface. This could have caused a flexing of the a i r f rame. If the locking pin, because of the hanging t r igger o r the maladjustment of the locking rod, was only partially engaged, the flexing of the a i r f r a m e could have been sufficient to disengage the lock completely and allow the outside air p ressure t o force the window open. If the a i rc ra f t had been p ressur ized , the positive p r e s s u r e inside the a i rc ra f t would have res is ted , if not totally overcome, the outside air p r e s s u r e that was crea ted by the velocity of the a i r c ra f t . This pressur iza t ion could have held the window in the closed position. Since the pressur iza t ion of the a i rc ra f t inc reases as soon as the a i rc ra f t leaves the ground, and the window is a plug type installation, it is probable, according t o the a i r c r a f t manufacturer , that the cocaptain could have closed the window in flight. This could have been accomplished only i f he were able to move the window into the window opening f r o m a fully r e t rac ted position. If this condition could have been met , the positive air p r e s s u r e inside the a i rc ra f t would then have ass is ted h im in closing the window. This condition i s purely analytical because the captain, before the cocaptain called, "Window- open, " had initiated rejected takeoff procedures , and the problem was then confined t o stopping the a i rcraf t .

A l l pilots a r e keenly aware of the possibility of an explosive device being placed on board the i r a i rcraf t . Any loud sound can logically cause a reflex react ion by a pilot t o keep his a i r c ra f t on the ground if he has not yet lifted off. The pilot usually has no way of a ssess ing immediately whether his a i r c ra f t has been rendered uncontrollable by an explosion or whether the loud sound was caused by something that would not affect control. Therefore , under the c i rcumstances , the pilot 's judgment to stop his a i r c ra f t on the ground ra the r than t o continue the takeoff is understandable.

The c rew kn'ew that the flight manual performance char t s f o r this aircraft indicated that they should be able to s top the a i rc ra f t f r o m a V1 speed of 150 knots within the confines of 11,400 feet of runway. This required distance allows f o r b rake re lease at maximum gross weight of 312, 000 pounds, reducing' this weight by about 2, 500 pounds due t o fuel burn during the accelerat ion t o 150 knots, then applying maximum hydraulic brakes and speed b rakes in o r d e r to stop the a i r c ra f t . The crew was aware that Runway 13R was 14,572 feet in length and that under the conditions described above, the a i rc ra f t should come to a stop with

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approximately 3, 000 feet of runway remaining. The crew was a l s o aware that the effect of engine r e v e r s e thrust was not considered i n calculating the stopping distance f r o m V1. These factors all combined to allay any thought by the captain that he would have any difficulty in stopping his a i r c ra f t on this runway by the use of prescr ibed p rocedures .

In this instance, the sound of an explosion occurred 3 seconds af ter the cocaptain had called V I . The a i rc ra f t had accelerated t o 154 knots at that t ime. Considering a l l of these conditions, the a i rc ra f t with all brakes operating would have stopped 2, 500 feet short of the end of the runway. Therefore, the captain 's decision to reject the takeoff was reasonable.

The c rew would have had an indication of the malfunctioning antiskid sys tem by the "RELEASE" indicator in the antiskid annunciator located on the panel above the captain's head. Th i s r e l e a s e indication would have appeared only during the takeoff run, and af ter the a i r c r a f t had accelera ted to a speed in excess of 20 knots, but would not have been apparent during the routine cockpit checks by the crew. The annunciator is not in the direct o r peripheral view of any c rewmember , and it i s not expected that any crewmember would he looking a t the annunciator during a takeoff run.

A walk-around inspection would not have revealed the presence of this type of malfunction in the antiskid system. T h e only indication available through such inspection, in regard to the condition of the b rakes , would be the wear indicator rods for each brake assembly. It was evident f r o m the number of landings (559 on the No. 1 front and 913 on the No. 1 r e a r - Appendix C) that these brakes had not been functioning during the high-speed portions of the landings f o r a considerable period of t ime. The maintenance representat ive, a s well as the crew, could only have assumed, by a l l outward indications, that the brakes were not worn below safe l imits and were operating in a normal manner. T h e r e was no maintenance requirement nor was the re a procedure by which the ent i re b rake sys tem was routinely checked. Only in the case of a n ent ire landing gea r change would t h e r e have been a functional check of the type necessa ry t o determine the existence of a malfunction of the kind that was experienced in this accident. P rogress ive checks would be performed on the a i rc ra f t if a pilot reported a braking o r antiskid problem that could not be isolated by a t e s t of individual components in the system. This testing could eventually lead t o the finding of a malfunctioning of the V - 3 relay, a s was experienced on this a i rcraf t . T h e r e had been no pilot r epor t s on this a i r c ra f t of any improper brake operation.

spe( use( f ror is d S i x -

S i x -

mur mac sho:

con; that the the

mar spet of t: I wit1

S U C

4 kl 700 init

tak, st01 tral the eve the

des the P r e

r - 17 -

Normal procedures for landing preclude the use of b rakes at speeds above 8 0 knots, and then, when the b rakes a r e applied they a r e used only with sufficient p r e s s u r e t o slow the .a i rcraf t f o r a turnoff f r o m the runway. The Board believes that under these conditions, it is doubtful that a pilot would be able t o detect the differences between six- o r eight-wheel braking. In actuality, the differences between a six- o r an eight-wheel braking would become evident only when a maximum braking effort was made. A maximum braking effort would be made only during a rejected takeoff o r a landing without r e v e r s e r s on a short runway.

At the t i m e the rejected takeoff was initiated, the c r e w did not consider that an emergency situation existed; they were not aware that the i r braking capability was reduced, but they were aware that the selected runway was 3 , 2 0 0 k e t longer than that required t o meet the accelerate /s top c r i t e r i a .

An analysis of the est imated stopping performance made by the manufacturer showed that the airplane might have accelerated t o V1 speed, under conditions approximating those which existed at the time of the accident, and st i l l have stopped within the confines of the runway with all brakes operating.

However, severa l fac tors combined to prevent the c rew f r o m successfully stopping the a i rc ra f t short of the end of t h e runway.

One fac tor is that the rejected takeoff was initiated at a speed 4 knots above V I . Th i s excess speed alone required a theoret ical 700-foot increase in stopping distance over that required f o r a n abort initiated at V1 speed.

Another factor was that the t ransi t ion segment of the rejected takeoff was over 1, 000 feet longer than that allowed by the acce le ra te / stop c r i t e r i a . This inc rease might have been the resul t of increased transition t imes o r the use of less- than-maximum braking effort by the c rew during the t ransi t ion period. Both of the aforementioned events might be attributed to the c r e w ' s lack of concern regarding their ability t o stop the airplane on the remaining runway.

Another significant factor was the deteriorat ion and subsequent destruction of the brakes a s a resul t of high-energy inputs. However, the fact that the b rakes were destructed was substantiated by the presence of numerous b rake pa r t s found on the l a s t 1, 000 feet of

r -

- 18 -

Runway 13R. The deter iorat ion occurred because the energy-absorption capacity of the six brakes was exceeded in the attempt to stop the airplane. The total energy required to stop the airplane ( 3 9 . 3 million foot- pounds fo r each of the s ix remaining brakes) was g r e a t e r than the demonstrated capability of 38. 7 million foot-pounds p e r brake.

The t i r e marks on the las t portcon of the runway were the resul t of side loading on the t i r e s a s the a i r c ra f t gradually turned to the right, plus the dragging produced by the s i x destroyed brakes . As the aircraft decelerated below 20 knots, the two good brakes on the No. 1 front and r e a r wheels would then become available but would have produced relatively little retarding force for the a i rc ra f t .

The t i r e s became deflated af ter the a i rcraf t came to a stop in the sand. The intense heat that had been generated in the brakes melted the fusible plugs in the wheels, and the t i r e s deflated. The width of the t i r e drag marks on the runway were s imi lar to those made by normally inflated t i r e s . The t i r e marks also lacked the charac ter i s t ic widening and narrowing made by a flat t i r e a s it flops on a rotating wheel. This evidence, plus the lack of any pieces of t i r e carcass left on the runway, substantiated the conclusion that the t i r e s were inflated until the a i r c ra f t came to a stop. Additionally, af ter the accident, the t i r e s ide- walls were in good condition, with no marks o r cuts that would have been produced by the weight of the a i rcraf t wheel rolling on a flat tire.

Catering supplies stacked in the galley a r e a were propelled into the a is les and galley exit a r e a during a i rcraf t deceleration, and, as a resul t , the movement of some passengers was impeded during the evacuation.

The right aft galley emergency slide was deployed, and, although reportedly activated by a crewmember , the slide did not inflate immediately. Fur the r , ear ly exit of the two midcabin c rewmembers left no one in authority to direct the evacuation f r o m this a rea . In other c i rcumstances , these conditions could adversely affect passenger survival.

2 . 2 Conclusions

( a ) Findings

1. The crew was trained, cert i f icated, and qualified in accordance with existing regulations.

tion c- >ot-

t of

:aft .d

- 19 -

2. The a i rc ra f t was certificated and maintained in accordance with the existing regulations.

3 . The a i rc ra f t weight and balance were within p resc r ibed l imits .

4. The flight was dispatched for a flight f r o m J F K to Shannon, Ireland.

5. The c r e w planned a flight f rom J F K t o Rijeka, Yugoslavia, overflying Shannon, Ireland.

6. The c r e w increased the fuel load without informing the dispatcher .

7. The copilot's sliding window was out of adjustment.

8 . The t r igger in the copilot 's sliding window handle hung in a midposition.

9 . The locking pin of the copilot 's sliding window only partially engaged the lockplate receptacle.

10. The window appeared to be closed and locked p r i o r t o the takeoff roll .

11. The window c a m e open during the takeoff run.

12 . The opening of the window resulted in the sound of an explosion.

1 3 . The a i rc ra f t had a malfunctioning V - 3 relay in the left antiskid control shield.

14. The malfunctioning V- 3 re lay rendered the b rakes inoperative above 2 0 knots on the No. 1 front and r e a r wheels.

15. The malfunctioning V - 3 relay had existed f o r a con- s iderable period of t ime.

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16. T h e r e was no maintenance requirement for a routine check of the ent i re brakeJantiskid s y s t e m that would have detected the malfunctioning V-3 relay.

17. At the t i m e of the attempted reject of the takeoff, the a i rc ra f t had s i x operating brakes.

18. The total b rake energy required t o stop the a i rp lane on the remaining runway was g r e a t e r than the demonstrated capability of the six operating b rakes .

19. The overloading of the available b rakes resul ted in excessive heat and the destruction of the b rakes p r i o r to the a i r c ra f t ' s coming to a stop.

20. The crew was unaware of the six-wheel braking configuration when the captain initiated the rejected takeoff procedures.

21. The a i r c r a f t had accelerated beyond the VI speed of 150 knots when the window came open.

22. There was sufficient runway on which t o stop the a i r - c ra f t with normal eight-wheel braking capability f r o m the 154 knot speed attained by the a i r c ra f t .

23. The c rew followed the p roper takeoff re jec t procedures .

24. The a i rc ra f t evacuation was accomplished in a timely fashion and was completed p r io r to the arrival of the a i rpor t emergency equipment.

25. The f i r e was effectively contained and extinguished by the a i rpor t f i r e department .

(b) Probable Cause

The National Transportat ion Safety Board determines that the probable cause of this accident was the unknown degraded capability of the heavily loaded a i rc ra f t ' s braking sys tem, which precluded stopping the a i rcraf t within the runway distance available. The reduced braking capability resulted f r o m a malfunctioning V-3 re lay in the left antiskid

- 21 -

control shield of the a i r c r a f t ' s braking system, which rendered two of the eight-wheel b rakes ineffective. A sound like that of an explosion in the cockpit during the takeoff ro l l caused the captain to re jec t the takeoff.

3 . RECOMMENDATIONS

The FAA is now reviewing maintenance requirements to de te r- mine if the need for a periodic routine inspection of the ent i re b rake and Mark I antiskid sys tem is in o rder . The FAA will advise the Safety Board of the action they will take, when they have completed the i r review.

BY THE NATIONAL TRANSPORTATION SAFETY BOARD:

JOHN H. REED Chairman

FRANCIS H. McADAMS Member

LOUIS M. THAYER Member

ISABEL A. BURGESS Member

WILLIAM R. HALEY Member

April 4, 1973.

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APPENDIX A: INVESTIGATION AND HEAR.ING

1. Investigation

The Board was notified of the accident at approximately 0115 on August 13, 1972, by the Fede ra l Aviation Administration and the Board 's New York Field Office. Personne l f r o m the New York office dispatched t o the scene established secur i ty and initiated the investigation. On Monday, August 14, 1972, th ree Washington based investigators were dispatched to a s sume control of the investigation. The team, ass i s ted by the two New York based investigators established working groups fo r Operations, Systems, Human Fac to r s , Cockpit Voice Recorder , and Flight Data Recorder . Pa r t i e s to the investigation included an Accredited Representative f r o m the Government of Yugoslavia, and representat ives f r o m Jugoslovenski Aerotransport , Fede ra l Aviation Administration, P o r t of New York and New J e r s e y Authority, The Boeing Company, and the Bri t ish Overseas Airways Corporation.

2 . Hearing

No public hearing was held in connection with this investigation.

1

i I

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APPENDIX B: CREW INFORMATION

The following is the crewmember information:

1. Pilot-in-Command:

Nationality:

Date of b i r th :

Type of license:

Date of original i ssue:

License valid to:

Date l icense renewed:

Last medics1 examination:

Last B-707 in-flight check:

Aircraf t flown (types):

Tota l flying hours:

Flight t ime B-707:

Pilot & Copilot (day & night)

B-707 flight time, l a s t :

90-days:

Previous accidents:

Flight t ime past 48 hours:

Res t af ter las t flight:

Captain Konstantin Spasojevic

Yugoslav

June 28, 1919

Airl ine Transpor t No. 14

September 1, 1951

October 21, 1972

Apri l 18, 1972

Apri l 4, 1972

Apri l 17, 1972

DC-3, CV-440, SE-210, B-707

14,943:37 hours

Not available

952:03 hours

Not available

230.48 hours

None

11 : 00 hours

30: 00 hours

2. Copilot (Cocaptain):

Nationality:

Date of bir th:

Type of l icense:

Date of original issue:

License valid to :

Date license renewed:

Las t medical examination:

Las t B-707 in-flight check:

Aircraft flown ( types):

Total flying hours :

Flight t i m e B-707:

Pilot & Copilot (day & night):

Flight Time, B-707, l a s t :

90-days:

Previous accidents:

Flight t ime past 48 hours :

Rest a f ter las t flight:

3. Flight Engineer:

Nationality:

Date of bir th:

APPENDIX B !4 -

Captain Radomir Pet rovic

Yugoslav

January 20, 1926

Airline Transpor t No. 42

July 30 , 1957

December 3 0 , 1972

June 27, 1972

June 22, 1972

June 18, 1972

1

DC-3, CV-440, IL-14, SE-210, B-707

1 1 , 302:58 hours

Not available

1,044:23 hours

Not available

210:36 hours

None

1 1 : 00 hours

30:OO hours

Nikola Jovanovic

Yugoslav

February 24, 1927

I 1

Type of l icense:

Date of original i ssue:

License valid to:

Date l icense renewed:

Las t medical examination:

Last B-707 in-flight check:

Aircraft flown ( types) :

Total flying hours :

Flight t ime, B-707:

707 Flight t ime , B-707, las t :

90 days:

Previous accidents:

Flight t i m e past 48 hours:

Rest a f ter l a s t flight:

~~

APPENDIX B 25 -

Flight Engineer 696

May 22, 1970

December 30, 1972

June 22, 1972

June 14, 1972

June 14, 1972

DC-3, IL-14, CV-440, SE-210, B-707

14,359:29 hours

1,202: 03 hours

Not available

259:47 hours

None

11 : 00 hours

30: 00 hours

In addition t o cabin attendants. were performing, t ime.

the flightcrew, the re were two pursuers and s i x All were currently qualified f o r the duties that they and they had received training within the specified

- 2 6 -

APPENDIX C: AIRCRAFT HISTORY

Aircraf t YU-AGA, a Boeing 707-321, s e r i a l no. 17601, was manu- factured on October 27, 1959. The las t ma jo r inspection was made on the a i rc ra f t 3, 398 hours p r io r to the accident. The las t equalized service was accomplished 1, 067 hours before the accident. The a i rc ra f t had accumulated 44, 272 flying hours up to the t ime of the accident.

The a i rc ra f t was originally owned and operated by P a n Amer ican World Airways a s N723PA. On May 14, 1970, the a i rc ra f t was leased t o Jugoslovenski Aerotransport by the GATX Bulk C a r r i e r Number T h r e e of Monrovia, Liberia. The a i rc ra f t was then regis tered in Yugoslavia as YU-AGA.

JAT and PAA entered into a maintenance contract on May 18, 1970, whereby PAA would provide worldwide maintenance of the a i rc ra f t . All modifications s p a r e pa r t s , changes in configuration, and recordkeeping would be done by PAA, and all se rv ice would be done to maintain the a i r - craft in a s ta te of airworthiness according to U. s. -FAA standards by means of scheduled and nonscheduled maintenance.

A review of the a i rc ra f t and component records showed that all required inspections and overhauls had been performed within the p r e - scr ibed t ime l imits and that the a i rc ra f t was maintained in accordance with the PAA procedures and the applicable FAA directives.

The PAA records of this a i rc ra f t disclosed the following:

Date of installation of b rakes by wheel position and number of landings accumulated.

Posit ion __ Date Landings Position Date Landings

1 F ron t 1 /3 /72 559 3 F ron t 6/29/72 182

1 Rea r 6120171 913 3 Rea r 4/2/72 369

2 Front 7130172 48 4 Front 6/29/72 182

2 Rea r 7130172 48 4 R e a r 6/29/72 182

The a i rc ra f t manufacturer and the brake manufacturer s ta ted that about 500 landings; under normal usage, comprised the average life of a brake unit.

1

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Documents

File N0.A-0001 - Online Collectionslibraryonline.erau.edu/online-full-text/ntsb/aircraft-accident-reports/... · File N0.A-0001 AIRCRAFT ACCIDENT REPORT Jugoslovenski Aerotransport