LOT Flight 5055

LOT Polish Airlines Flight 5055

SP-LBG, the aircraft involved in the accident, at London Heathrow Airport in April 1987
Accident summary
Date May 9, 1987
Summary Uncontained engine failure, in-flight fire, progressive electrical failure, loss of flight controls, engine manufacturing and design flaws
Site Warsaw, Poland
Passengers 172
Crew 11
Fatalities 183 (all)
Aircraft type Ilyushin Il-62M
Aircraft name Tadeusz Kościuszko
Operator LOT Polish Airlines
Registration SP-LBG
Flight origin Warsaw Frederic Chopin Airport, Poland
Destination John F. Kennedy International Airport, New York City, U.S.

LOT Flight 5055 was an Ilyushin Il-62M of LOT Polish Airlines that crashed in the late morning hours of Saturday, May 9, 1987. The event happened in the Kabaty Woods nature reserve on the outskirts of Warsaw, Poland. The flight prepared to leave from Warsaw to New York City's John F. Kennedy International airport when it encountered multiple catastrophic events with the numbers 1 and 2 engines as well as the elevator shortly after departure. All 183 passengers and crew on board perished in the crash. The accident was the deadliest of any involving an Ilyushin Il-62, the deadliest to occur on Polish soil, and the deadliest aviation accident of 1987. It was determined to have been caused by the disintegration of an engine shaft due to faulty bearings.

Aircraft

The aircraft was a 186-seat Ilyushin Il-62M built in the third quarter of 1983, registered SP-LBG and named Tadeusz Kościuszko, after the Polish military leader and national hero.

Passengers and crew

NationalityPassengersCrewTotal
 Poland15511166
 United States17017
Total17211183

The captain was Zygmunt Pawlaczyk (59), with 19,745 flight hours' experience (5,542 on Ilyushin Il-62s), and a captain of the type from 11 May 1978. The first officer was Leopold Karcher (44); the remaining crew were flight engineer Wojciech Kłossek (43); the flight navigator Lesław Łykowski (47); the radio operator Lesław Bogdan (43); and Ryszard Chmielewski (53), a trainer of flight engineers on a routine observation of the progress of Kłossek. Chmielewski had been scheduled as a flight engineer on LOT Polish Airlines Flight 007, another Il-62 which had crashed seven years earlier, but had been ill and had switched shifts with a colleague.

The purser was Maria Berger-Sanderska (38); the other flight attendants were Hanna Chęcińska (35), Małgorzata Ostrowska (29), Beata Płonka (23), and Jolanta Potyra (40). Chęcińska was in the technical cabin-bay, between the engines, and probably either lost consciousness and burned in the fire or was sucked out of the aircraft after decompression; her body was never found despite an extensive search.

155 of the passengers were from Poland, while the other 17 were from the United States.

Accident summary

Memorial to the crash victims

The chartered aircraft to New York City took off from runway 33 at Okęcie Airport at 10:18 a.m. The flight was to continue to San Francisco after refuelling in New York. The pilots were cleared to climb to 31,000 feet (9,400 m), on a course set to Grudziądz VHF omnidirectional range (VOR), which was reached at 26,500 feet (8,100 m). Soon after Flight 5055 took off from Warsaw, the crew was instructed by air traffic control (ATC) to climb to an altitude of 18,000 feet (5,500 m) as quickly as possible:

10:26 Flight 5055 Well, we go to New York, possibly we'll be able to get to flight level 180... (tongue-in-cheek)
10:26 Okęcie ATC Gentlemen! You won't make it. You have about 5 kilometres (3.1 mi) to the TMN [Tango-Mike-November route]. I told you that clearance was set for 180 or higher. Military planes are training there. I have no communication with them to allow separation.
10:26 Flight 5055 Roger that. Roger that.
10:31:35 Area Control 5055, heading 310, immediately cut flight level 170 [17,000 feet (5,200 m)].
10:31:39 Flight 5055 5055, heading 310.
10:31:41 Area Control Climb immediately. I mean it, immediately.

At that moment, the crew applied maximum thrust on the engines to climb to 18,000 feet (5,500 m). Supposedly, had they not applied thrust, the turbine disc in the inner left (No. 2) engine would have survived the entire flight. However, nine minutes after the thrust was applied, the faulty bearings inside the engine overheated enough (to about 1,000 °C or 1,800 °F) to cause an explosion.

Engine no. 2 exploded and started burning at 10.41:28 a.m., as the aircraft had just passed Lipinki village, near Warlubie (near Grudziądz, at 8,200 metres (26,900 ft), at a speed of 810 kilometres per hour (500 mph)). The overheated bearings exploded, destroying the shaft; the turbine disc on the burning engine separated from the destroyed shaft; the freed disc spun to an enormous speed and, within seconds, explosively disintegrated, destroying it. Debris from the explosion violently spread around (with an estimated speed of 160 metres per second (520 ft/s)), puncturing the fuselage, severing flight controls and electrical cables, and causing severe damage to engine No. 1 — the outer left one, which soon also started to burn. A piece of hot debris burst into cargo hold number 4 and caused a rapidly spreading fire; the inner left engine burned rapidly until impact.

Immediately, the crew noticed that the elevator control systems had failed — only the pitch trim remained operative — and that two engines were disabled. The reasons for this were unknown to the crew; they initially suspected that the aircraft could have been hit by something, possibly another aircraft. The pilots started an emergency descent to 13,200 ft (4,000 m). The closest airport where the Il-62 might land was Gdańsk, but landing there was not possible because the crew could not dump enough fuel for the emergency landing attempt (the takeoff weight of the aircraft on that day was 167 tons, until 10:41 approximately 6 tons of fuel were consumed; the maximum landing weight of the Il-62M was 107 tons) so they turned their heading to Okęcie instead. Due to the damaged electrical system, the crew had problems with fuel dumping and they did not realize that the fire had spread to the cargo holds in the back of the aircraft (cargo holds 4 and 6), and in the final minutes probably spread into the passenger cabin.

Initially, the crew intended to land at the military airport in Modlin, but at the final moment they decided to return to Okęcie, where there was better emergency equipment. It was unclear at the time why the crew decided to continue the flight to Warsaw, given the rapidly spreading fire and lost flight controls, rather than land as quickly as possible at Modlin. Modlin's emergency equipment was not as good as Okęcie's, but still good enough to deal with an emergency landing of an airliner with an in-flight fire. Many at the time believed officials had decided the airliner must not land at a military airport and (contrary to official reports) denied the crew's request to land at Modlin. While this is somewhat plausible, no conclusive evidence supporting this theory was ever presented. The most probable hypothesis is that due to damage to the electrical systems, both the fire detectors in the cargo hold and inside the engine did not work properly (on the cockpit voice recorder (CVR), an engine fire warning was heard shortly after the explosion, but it later faded out; the signal reappeared less than four minutes before the crash and continued until impact) and so Cpt. Pawlaczyk did not know about the magnitude of the fire in the hold and how quickly it was spreading, nor about the burning engine when he decided to fly to Warsaw.

At 10:53, an explosion in the cargo hold occurred; the reasons are unknown. It is supposed that some of the fuel tanks were damaged and fuel vapors drifted into the burning cargo hold, causing an explosion.

The passengers were fully aware of the emergency; 58-year-old passenger Halina Domeracka managed to write on the opening page of her copy of the New Testament Bible: 9.05.1987 The aircraft's damaged... God, what will happen now... Halina Domeracka, R. Tagore St., Warsaw...

CVR fragment — the moment of engine explosion

10.41.28 Intermittent acoustic signal of autopilot disengagement

10.41.30 Crew: Hey! Pressurization!

10.41.32 Acoustic ringing signal of cabin decompression

10.41.34 Crew: Is there a fire? What's going on?

10.41.35 Crew: Probably a fire.

10.41.37 Crew: Engine? Shut it down!

10.41.39 Crew: ...shut down. That first one is burning!

10.41.42 Crew: ...fire...

10.41.44 Crew: ...all small [referring to engines' throttles]

10.41.45 Crew: Warsaw?

10.41.46 Crew: ...all small. Decompression.

10.41.48 Crew: Two engines are gone!

10.41.49 Continuous acoustic signal of engine fire.

10.41.50 Crew: Two engines are gone! [...] Shut down... [...] We're turning around! Fire!

10.41.55 Crew: Danger!!! Warsaw radar LOT! Warsaw radar! [calling flight control]

The crew tried to land at Okęcie from the south (due to strong wind) and turned the aircraft 180 degrees to runway 33 but a rapidly spreading in-flight fire, which spread to the exterior of the aircraft (which was trailing a huge flame and dense black smoke), caused a total failure of surviving flight controls, including the pitch trim. The landing gear also was not functioning. The emergency fuel dumping pumps were also malfunctioning; sometimes they stopped functioning at all, only to resume dumping fuel minutes later. At the moment of the crash, approximately 32 tons of fuel were still in the tanks. A very straight turn to the left was started at 11.09 at 4,900 ft (1,500 m) with an airspeed of 480 kilometres per hour (300 mph). At the moment the aircraft passed the village of Józefosław, approximately 10 kilometres (6.2 mi) from the airport, several burnt-out elements of its fuselage fell out, starting local fires on the ground. Supposedly, at this moment the fire destroyed the pitch trim controls. When the aircraft passed the town of Piaseczno, it went into sinusoid-shaped flight for the final seconds and nose-dived with a slight 11 degrees left bank and 12 degree pitch downwards, crashing into the ground at 475 kilometres per hour (295 mph) and exploding into pieces in the forest 5,700 metres (18,700 ft) from the Warsaw airport runway. (As the nose dive started very shortly before the crash, one hypothesis states that in the final moments, fire from the cargo hold spread into the rear part of passenger cabin, causing mass panic; the passengers moved towards the nose of the aircraft, away from the fire, destabilizing the aircraft and causing the dive. Another is that rapidly spreading fire deformed the fuselage in its rear, which — combined with strong forces acting on the empennage – altered the aircraft's angle of attack and contributed to the rapid dive.) The wreckage was scattered over a rectangular area, approximately 370 by 50 metres (1,210 by 160 ft).

11.09.47 am

Okęcie Tower: From your current position you have about 15 kilometres (9.3 mi) to the runway.

Crew: Understood.

Crew: ...[turn] to the left! Engines to the left!

11.10.13 am

Tower: 5055, to the left, to the left zero-five-zero.

Crew: OK.

11.10.40 am

Tower: 5055, to the left, course 360.

Crew: We want to turn. That's just what we want. [implied meaning: "we're trying"]

Tower: Keep turning, turn to three-six-zero. Now you have about 12 kilometres (7.5 mi) to the runway.

Crew: OK.

11.11.02 am

Tower: 5055, to the left, course 330.

Crew: We are turning to the left.

Tower: Start final approach about 11 kilometres (6.8 mi) from the runway.

Crew: We will do all we can.

Tower: Understood.

Tower: [Turn] to the left, course 320.

Crew: Understood.

11.11.34 am

Tower: You've come to the right hand side of the runway centerline, continue left, course 300.

Tower: Wind is 290 degrees, 22 kilometres per hour (14 mph). You are cleared for runway three-three.

Crew: OK.

11.12.10 am

Transmitter turned on four times; fragments of unintelligible utterances

11.12.13 am

Crew: Good night! Goodbye! Bye, we're dying!

The last words inside the cockpit recorded by the CVR at 11:12:13 were: "Dobranoc! Do widzenia! Cześć, giniemy!" (eng. Good night! Goodbye! Bye, we're dying!). All 172 passengers and 11 crew died as the aircraft broke apart and crashed.

Cause

After the crash of the Il-62 operating as LOT Polish Airlines Flight 007, the airline had started replacing its Ilyushin Il-62s with the more modernized Ilyushin Il-62M version. These had newer engines (Soloviev D-30 instead of Kuznetsov NK-8), but both of these turbofan engines shared the same critical point — low pressure turbine and engine shaft design and construction.

A roller bearing. The circular ring is the 'race' that the rollers run in.

According to the Polish investigatory commission, the cause of the crash was the disintegration of an engine shaft due to faulty bearings inside the number 2 engine which seized, causing extensive heat. This in turn caused the consequent damage to engine number 1 (and its fire), rapid decompression of the hull, a fire in the cargo hold (which was not detected due to a damaged fire alarm system sensor), as well as the loss of elevator controls and progressive electrical failure.

The bearings concerned were roller bearings; each was designed to have 26 rollers inside, but because the supply of the rollers to the factory was delayed — while the bearings had to be finished on time due to expiring contracts — each bearing had only 13 rollers[1]

Aftermath

The Okęcie Airport fire crew was aware of the emergency; when the aircraft crashed they immediately drove towards the crash site, but they did not manage to reach it because the truck could not pass through the gaps between the trees.

The day was warm and sunny, so many people rested in the vicinity of Kabaty Woods; after the crash many of them headed for the site. According to official reports, the site was quickly closed to the public, and no plundering of remains was officially registered. However, some unofficial reports about stealing money and valuable items surfaced later; Halina Domeracka's personal belongings, including her passport, New Testament Bible, photos, and glasses were recovered intact from the site, yet 400 U.S. dollars and 10,000 Polish zlotys were missing.

Because some burning pieces of hull fell out, several local fires were initiated on the ground, propagated by the dumped fuel; all of them were extinguished by 12:00. A total of 195 firemen from 44 different units participated.

All victims' bodies were dismembered in the crash; from a total of 183 bodies, 62 were never identified.

All crew members posthumously received high military and civil decorations: Cpt. Pawlaczyk was given the Officers' Cross of Polonia Restituta, other flight crew members received the Knights' Cross of the same order, and the flight attendants received the Golden Cross Of Merit. The state funeral of the crew was conducted on 23 May 1987 at the Northern Communal Cemetery in Warsaw. The graves of the crew of LOT Polish Airlines Flight 007 are located a few hundred meters away.

Two days of national mourning were announced after the crash. Many officials from the entire world, including Pope John Paul II, expressed their condolences to the families of the victims.

The accident's cause was similar to that of LOT Polish Airlines Flight 007's crash seven years earlier. After the disaster of Flight 007, the Polish investigatory commission established that its engine shaft disintegration was the result of metal fatigue; improper alloy preparation resulting in a defective mechanism which was less resistant to fatigue; and a faulty design of the engine shaft. Detection of these faults was possible only after complete disassembly of the engine and detailed analysis of all its elements, and as such was beyond the capabilities of aircraft maintenance personnel. These concerns were addressed by the Polish Government's Special Disasters Commission in the 1980 inquiry, but the Soviet designers, engineers and scientists disagreed with these findings, stating that the turbine disintegration was the result of engine failure, not its cause.

After Flight 5055's demise, a similar report was sent to Moscow but was initially dismissed by the Soviet engineers and politicians. The Soviet engineers even made their own report, concluding that all damage to the engines were the consequence of the crash, which was caused by pilot error. However, despite pressure and threats from the Soviets, the Polish commission stood by its findings; finally, Soviet engineers and politicians reluctantly accepted responsibility. Soon after the crash, LOT Polish Airlines, still being unable to purchase non-Soviet aircraft, implemented several improvements in the Il-62s' construction:

Today

The crash site in 2009

After the crash, the place where Flight 5055 came down and exploded was — during three months of cleanup — ploughed and sown with new trees. As of 2016, the long scar in the forest is still perfectly visible from the sky. On the north edge of the scar is a monument – a high, black Christian cross and a black stone engraved with the names of the crash victims. In Ursynów district there is a Zygmunt Pawlaczyk street, and through Kabaty Forest runs a grove of trees named for the Kościuszko.

Symbolic graves of the crew members lie in Powązki Military Cemetery, and a collective grave of unidentified victims lies in Wólka Węglowa Cemetery – the place where the victims were identified. Some identified victims were also buried there; others were buried in their hometowns.

See also

References

  1. Antoni Milkiewicz. Jeszcze o Lesie Kabackim (October 1991), AERO–Technika Lotnicza, Warsaw: Oficyna Wydawnicza Simp-Simpress: 12–14, ISSN 0867-6720 Missing or empty |title= (help)
External image
Pre-crash photos of the airliner at airliners.net

Coordinates: 52°06′48″N 21°02′40″E / 52.11333°N 21.04444°E / 52.11333; 21.04444

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