Under the Iron Curtain: The crashes of LOT Polish Airlines flights 007 and 5055
Note: this accident was previously featured in episode 9 of the plane crash series on November 4th, 2017, prior to the series’ arrival on Medium. This article is written without reference to and supersedes the original.
On the 9th of May 1987, the worst air disaster in Polish history unfolded over 31 minutes in the skies above Warsaw, as the pilots of a badly damaged Ilyushin Il-62M struggled to save the lives of 183 passengers and crew. Despite two failed engines, an explosive decompression, inoperative elevators, myriad electrical problems, and a raging fire in the hold, they managed to maneuver their stricken plane to within sight of the airport — only to plunge into a forest five kilometers short of the runway, killing everyone on board, their desperate last moments broadcast to the world: “Goodnight, goodbye! Bye, we’re dying!”
When investigators discovered the source of the catastrophic engine failure which triggered the disaster, it was noted that this was hardly the first time this had happened. Seven years earlier, on the 14th of March 1980, another LOT Polish Airlines Ilyushin Il-62 suffered an uncontained engine failure during an attempted go-around, crashing seconds later with the loss of all 87 passengers and crew. In both crashes, a key shaft had broken, leading to an explosive failure which sent debris ricocheting through the aft fuselage, damaging critical controls. Both disasters appeared to have been caused by poor workmanship in the Il-62’s Soviet-built engines, but beyond these basic details, information is sketchy. Why exactly these defects were introduced, and whether LOT could have detected them, remain subject to disagreement, as does much else about the twin disasters. In fact, the truth itself seems to have been a casualty of the disaster in the Kabaty woods — swept away into the maelstrom of hearsay and speculation which has long bedeviled any attempt to elucidate the causes of air disasters behind the Iron Curtain.
Before telling the story of the two ill-fated Il-62s, it is necessary to briefly break the fourth wall and discuss what it means to analyze a crash from the Eastern bloc. Today, we are used to an international aviation industry where experiences are shared and the principles of transparency are near-universal, with a few notable exceptions. If an air crash were to happen tomorrow in any of the vast majority of the world’s nations, we could reasonably expect, in two or three years’ time, the publication an official report written with reference to Annex 13 of the Chicago Convention on Civil Aviation, which states, among other provisions, that the goal of an accident investigation is to find facts and enhance safety, and not to apportion blame. However, in the former Warsaw Pact, this was not the case, as the USSR and its allies, including communist Poland, did not treat air crashes as a matter of public interest. In the Soviet Union, newspapers typically were not even allowed to report on a plane crash unless foreigners were among the dead, and official investigations were brief and secretive. The technical knowledge and capabilities of Eastern bloc investigators were no less than their Western counterparts, but their political realities were different, in that the official purpose of an accident investigation was not solely to enhance safety, but to determine whether a crime had been committed. If there was no crime, the investigation would cease. The state apparatus responsible for air travel and air safety would act unilaterally to make any safety improvements which it deemed necessary upon consultation with the investigators, but the assembly of a detailed and authoritative record of what happened and why was of diminished importance.
This fact has made researching air disasters in Soviet and Soviet-aligned countries exceedingly difficult. Although the once-secret investigation materials are no longer hidden, they leave much to be desired in terms of completeness, which has in turn made room for both complementary and competing accounts of what happened. In researching the crashes of LOT flights 5055 and 007, it quickly became apparent that there were only a few basic facts which were consistent throughout every retelling, not necessarily because their authors disagreed with one another, but because the absence of an authoritative record has led to increased reliance on witness recollections and open speculation. Therefore, as one reads this account, it should be kept in mind that much of what follows is based on my personal attempts to reconcile these disparate sources of information, and that in contrast to most of my analyses, only some basic points come from the official accident report, which at some 5,000 words was shorter than this article.
In 1972, LOT Polish Airlines, the flag carrier of the Polish People’s Republic, took delivery of its first ever long range jet airliner, the Soviet-built Ilyushin Il-62. With room for up to 200 passengers, the Il-62 was the largest passenger jet ever built when it entered service in 1963, significantly exceeding the size of the superficially similar Vickers VC-10. The Il-62 featured an unusual engine layout, with all four engines attached to the rear fuselage, a format shared among passenger airliners only by the VC-10. Although some Western commentators speculated that the Il-62 was copied from the British-made VC-10, the weight of the evidence suggests that this was at most a loose inspiration, and in fact the Il-62 went on to be the more successful of the two aircraft, with a total of 292 constructed between 1963 and 1995. And at least one other superlative is worth noting, namely that the Il-62 was the largest airliner to lack hydraulically assisted flight controls, relying purely on cables and push rods to move the control surfaces.
As soon as it took delivery of its first Il-62s, LOT began operating them on transatlantic routes, first to destinations in Canada, then to New York, and later Chicago. By that point, Western airlines were able to make similar trips non-stop using the new generation of wide body airliners, including the Boeing 747 and McDonnell Douglas DC-10, but the narrow body Il-62 was part of an earlier generation of jets which could not make the crossing in a single leg, so the flights had to stop in Gander, Newfoundland to refuel.
LOT’s very first Il-62, registered as SP-LAA and nicknamed “Mikołaj Kopernik,” remained in service for eight years, until one fateful late-winter morning in 1980.
On the night of the 13th of March that year, SP-LAA departed New York’s John F. Kennedy International Airport on flight 007 to Warsaw via Gander. On board were 77 passengers and 10 crew, including no less than five cockpit crewmembers, consisting of 46-year-old Captain Paweł Lipowczan, First Officer Tadeusz Łochocki, and Flight Engineer Jan Łubniewski, as well as a navigator and radio operator. The passengers also included Polish singer Anna Jantar, and 22 boxers and support staff from the United States amateur boxing team.
Apart from a two-hour delay due to a snowstorm, the flight proceeded without incident across the Atlantic throughout the night and into the following morning. Shortly after 11:00 local time on the 14th of March, flight 007 arrived over Warsaw and lined up to land on runway 15 at Warsaw Okęcie Airport. On final approach at an altitude of just a few hundred meters, the pilots extended the flaps and landing gear — and it was at that moment that things first started to go wrong, because the gear position lights for the main landing gear failed to illuminate.
Unsure whether the main gear was down and locked, the pilots informed air traffic control that they had problems with their landing gear and would cut the approach short to troubleshoot the issue. The controllers are said to have looked at the plane through their binoculars and determined the gear to be down, but it was impossible to tell from a distance whether it was properly locked. And so the controller told flight 007, “Roger, [climb] runway heading and altitude 650 meters.”
“Runway heading and 650,” the radio operator replied.
At that moment, Flight Engineer Łubniewski pushed the thrust levers forward to go-around power, abandoning the landing at a height of 250 meters. The engines spooled up over several seconds — and then, with a deafening explosion, the №2 engine, in the inboard position on the left side, violently disintegrated. Fragments of the low pressure turbine disk, traveling at a speed of 200 meters per second, were thrown in several directions; one struck the adjacent №1 engine, causing it to fail immediately. A second flew harmlessly out into space, but a third chunk passed clean through the fuselage, slicing electrical wires and control cables, before it struck the №3 engine in the inboard position on the right side, causing it to fail, too. Both black boxes went dead, and controllers watched in horror as the Il-62 pitched over, veered to the right, and plunged to the ground, throwing up a towering plume of fire and smoke just short of runway 15.
Emergency services rushed immediately to the scene, where they found that the Il-62 had impacted the embankment of a moat surrounding a 19th-century fortress, narrowly missing the barracks at an adjacent juvenile correction facility. The shattered remnants of the plane were strewn across the embankment, the moat, and adjacent streets, having been pulverized beyond recognition; the only intact portion of the airplane was its tail, lying askew beside the frozen ice floes on the moat. None of the 87 people on board had survived.
The investigation into the crash of LOT flight 007 was short, lasting less than two months before it was quietly ordered to cease, apparently because investigators had failed to establish the commission of a crime. The investigators’ final report, if one was ever written, has not been released. But various sources have since shed light on what they allegedly found.
According to these sources, investigators found fragments of the №2 engine on the ground 2 km before the crash site, having apparently been ejected in flight. These fragments came from the low pressure turbine disk, and the damage to the fragments showed that the disk had not failed due to metal fatigue, but had rather been ripped apart by centrifugal forces in a severe overspeed event.
The base model Il-62 involved in the accident was powered by four Kuznetsov NK-8 low bypass turbofan engines. Like all turbofan engines, the NK-8 produced thrust both via its exhaust and by so-called bypass air forced backwards by the fan at the front of the engine. To produce this exhaust and rotate the fan, fuel is mixed with airflow through the engine core and ignited in the combustion chamber, causing it to expand and increase in pressure. This pressurized air then flows rearward, where it spins the turbine. The turbine then drives a compressor which further accelerates the airflow, creating thrust. Like most jet engines, however, the Kuznetsov NK-8 featured two separate turbines: a high-pressure turbine whose job was solely to drive a compressor, and a low-pressure turbine to power the fan, which in turn created additional thrust by accelerating bypass air around the exterior of the engine core. The low-pressure and high-pressure turbines were connected to the corresponding low-pressure and high-pressure compressor sections. Each compressor section consisted of several disks of progressively decreasing size that pressurized the airflow by absorbing the mechanical power produced by the turbines, which would otherwise accelerate indefinitely until they ripped themselves apart.
On the NK-8 engine, the two-stage low-pressure turbine at the rear of the engine was connected to the fan and the low-pressure compressor at the front of the engine via the low-pressure or LP turbine shaft. The LP turbine shaft rotated inside of the shorter but larger-diameter high-pressure, or HP turbine shaft, which connected the single-stage high-pressure turbine to the high-pressure compressor. When investigators pulled the LP turbine shaft from the wreckage of flight 007, they found the smoking gun: the heavy shaft had broken into two pieces, not due to the impact, but due to metal fatigue. At some point — perhaps when the shaft was originally manufactured — a machining tool had left an abnormally deep scratch on its inner bore, creating a weak point which eventually developed into a crack. This crack expanded with every application of takeoff power, until the shaft finally snapped in two when Flight Engineer Jan Łubniewski applied full power for the go-around on flight 007.
When the shaft broke, the LP turbine lost its connection to the LP compressor. Without the compressor dragging it down, so to speak, there was nothing to stop the turbine from accelerating indefinitely under the force of the hot gas flow out of the combustion chamber. Within 0.1 second, the turbine accelerated to 130% of its red line speed, at which point sheer centrifugal force tore the second stage LP turbine disk into three equally sized pieces. One of these immediately destroyed the adjacent №1 engine. As many commentators have noted, this represented a major deficiency in the very concept of a four-engine plane with rear-mounted engines; namely, that an uncontained failure of one engine almost always resulted in the destruction of the engine next to it as well. But in this case, that was not the most consequential effect of the failure.
The reason that the engine explosion led to the crash was revealed when investigators examined the push rods used to transfer pilot inputs to the fully mechanical flight control surfaces in the tail. As it turned out, these push rods had been cut by flying debris, leaving material deposits which investigators were able to match with the LP turbine disk. Based on this analysis, and examinations of other debris, investigators determined that one of the disk fragments entered the left side of the fuselage, cut the push rods which controlled both the elevators and the rudder, then passed out the right side of the fuselage, where it destroyed the №3 engine.
Here it is worth noting another design deficiency: unlike similar Western models, the Il-62 had no redundancy in its control system, as Soviet certification regulations did not require it at the time. Western passenger jets typically have split controls: that is, when the controls are mechanically operated, there are separate sets of cables and/or push rods for the captain and first officer, such that if one set fails, the other can still be used to maintain control. The Il-62, on the other hand, did not have this safety net. Consequently, the pilots lost control over the elevators and rudder. With the loss of three engines, the plane could not maintain altitude and began to descend; asymmetric thrust also caused it enter a slip. But when the pilots attempted to pull out of the descent and counter the slip, they found that their controls had no effect. Twenty-six seconds after the failure, flight 007 descended straight into the ground, pitched 13 degrees nose down and in a slight bank. Control perhaps could have been recovered, given time: it was in fact still possible to control the pitch of the airplane using the horizontal stabilizer, which will be described in more detail later. However, due to their low altitude, the pilots probably had insufficient time to explore alternate means of control before the plane struck the ground.
For the next 30 years, the case more or less ended there: the authorities made a brief announcement stating that the cause of the crash was poor workmanship during manufacture of the LP turbine shaft in the Soviet Union, and the country moved on. But as it turned out, that wasn’t the whole story — in fact, the investigation allegedly revealed several other important details which were kept secret, until they were apparently rediscovered by Newsweek in 2010.
According to the documents, which were declassified after the revolution of 1989, Polish aviation officials had long been aware of quality control problems involving Kuznetsov NK-8 engines manufactured in the Soviet Union. These engines came with a planned interval between overhauls of 5,000 hours, but in practice, 24 out of 50 NK-8 engines in LOT’s fleet failed before reaching 5,000 hours of operation. This terrible failure rate has been blamed on poor build quality, although at least one source speculates that LOT incurred accelerated wear and tear because of a practice of using greater than normal thrust on takeoff, apparently in order to lift off from the relatively short runway at Warsaw Okęcie Airport while tankering fuel, which was much cheaper in Poland than it was overseas.
However, despite the unreliability of these engines, when errors of leadership led to an economic crisis in Poland in the mid-1970s, orders came down from the highest level to reduce costs associated with the state-run LOT Polish Airlines, and among the areas placed on the chopping block were the scheduled engine overhauls. The overhauls could only be accomplished by the manufacturer in the USSR at a significant cost, which Polish authorities apparently thought was unreasonably high. In order to reduce these costs, they produced a report which allegedly presented research showing that NK-8 engines could be safely operated for up to 8,600 hours between overhauls. This report was referenced only indirectly in communications between LOT and the engine manufacturer, and some modern accounts cast doubt on whether it ever actually existed. In any case, the Russians were understandably skeptical, and they informed LOT that they would not take responsibility beyond the 5,000-hour limit — anything that happened after that was Poland’s problem.
In practice, LOT tried to limit the consequences of its own cost-saving decision by making sure that no Il-62 was fitted with more than one engine that was over the original 5,000-hour limit. Each plane therefore should have had three “good” engines and one that was grossly over the warranty, referred to as the “leader.” This spread out the risk somewhat, but it also resulted in an abnormally large number of LOT Il-62s being ferried back home from overseas on three engines without passengers. In practice, however, even this bootleg rule was not always followed — in fact, on SP-LAA “Mikołaj Kopernik,” three of the four engines were “leaders,” of which the failed engine was actually the newest. Still, that particular engine had a troubled history, beginning with a failure in 1975 when it had only 1,700 hours. The engine was repaired and returned to service, but in 1979 it was allegedly removed again due to excessive vibrations, only to be installed back on SP-LAA without having been fixed, supposedly because the vibrations were within the manufacturer’s limits. It has been speculated that these vibrations may have been a sign of the impending failure of the low-pressure turbine shaft. Nevertheless, the airline continued to operate it past the 5,000-hour limit.
In the end, however, any contribution to the accident that LOT’s maintenance decisions may have had was swept under the rug. The official investigation was informally halted in April 1980, and was officially closed the following year without releasing a comprehensive report. And the engines’ Soviet manufacturer never accepted even the preliminary findings, arguing instead that the damage to the turbine shaft was the result of the crash, not its cause. On the other hand, a Polish forensic analysis raised the possibility that the faulty machining groove was actually created during a botched repair attempt in Poland, a discovery which was apparently hidden from Soviet investigators.
In one final irony, the investigation was also said to have concluded that the landing gear problem which prompted flight 007’s ill-fated go-around, setting the whole sequence of events in motion, was nothing more than a burnt-out light bulb.
After the crash of flight 007, LOT pilots briefly mutinied, refusing to fly planes with “leader” engines. Under pressure, LOT apparently caved, as some sources say they ended the practice. This appeared to satisfy the crews, who in the meantime had taken to calling the Il-62s “flying coffins.”
Shortly thereafter, the airline began replacing its original Il-62s with Ilyushin’s new, upgraded Il-62M, which came with more efficient Soloviev D-30 KU engines and an extra fuel tank in the tail which allowed it to fly from Warsaw to New York without stopping in Gander. These engines would also be more strictly controlled for reliability, with an overhaul every 3,000 hours instead of every 5,000.
Among these new Il-62Ms was SP-LBG, nicknamed “Tadeusz Kościuszko,” which was delivered to LOT in 1983. The first four years of this airplane’s life were uneventful, until the morning of the 9th of May 1987, where we will pick up its story.
That day, “Tadeusz Kościuszko” was scheduled to operate LOT flight 5055 direct from Warsaw to New York, reversing the route flown by flight 007 in 1980. The plane that day was almost fully booked, a relative rarity on flights between the Western and Eastern blocs, with 172 passengers and 11 crew on board. A 173rd passenger was saved by a stroke of good fortune — she was arrested just before boarding for failure to declare a fur coat at customs.
In command that day was 59-year-old Captain Zygmunt Pawlaczyk, a veteran pilot with over 19,000 flying hours. Assisting him were no less than five other flight crewmembers, consisting of 44-year-old First Officer Leopold Karcher, 43-year-old Flight Engineer Wojciech Kłossek, 47-year-old Navigator Lesław Łykowski, 43-year-old Radio Operator Leszek Bogdan, and 53-year-old Flight Engineer instructor Ryszard Chmielewski, who was on board to monitor Kłossek’s performance.
With its passengers loaded and its fuel tanks full to the brim, flight 5055 to New York taxied out and took off from Warsaw Okęcie Airport at 10:18 local time, climbing away without the slightest hint of trouble. As they climbed, the crew contacted the Warsaw approach controller, who gave the flight its next clearance: “Hello, LOT 5055, I can see you after takeoff. Turn left heading 290, climb to level 280, [cross] TMN 180 or higher.”
The controller wanted the flight to cross the TMN navigational beacon at a height of at least 18,000 feet (or flight level 180) because of military aircraft which were operating at 17,000 feet in the area beyond the beacon.
Radio Operator Bogdan read back the clearance correctly, and flight 5055 continued its climb. But at 10:26, the controller called again: “5055, ten kilometers to TMN,” he said. “Will you guys cross level 180 within ten kilometers?”
“No, not exactly 180, but climbing out of 170,” Bogdan replied.
“Climb to level 160,” the controller said. “Hold this level until Grudziądz.” If flight 5055 couldn’t reach 18,000 feet to pass over the military training area, then they would simply have to pass under it instead.
“Well, we’re flying to New York, we might have to cross level 180,” Bogdan jokingly replied.
“Gentlemen! You won’t make it in time, because there are only five kilometers left to TMN,” the controller warned. “I said at the very beginning that the clearance was to cross TMN at 180 or higher. Military planes are flying there and I unfortunately have no contact with them to separate you.”
“Roger, roger,” Bogdan replied.
“Hold level 160, you’re on your way to TMN now,” the controller repeated. “Further ascent will be from that area. For now, contact frequency 134.87. Goodbye, we’ll speak again soon.”
“Roger, see you later, we’ll speak again soon, LOT 5055,” said the Radio Operator.
Five minutes later, at 10:31, the Warsaw area controller called the flight and said, “5055, climb level 310 and cut across level 170 immediately.”
“LOT 5055, we will report. We’re going to 310,” Bogdan replied.
“Immediately, I mean immediately,” the controller emphasized. He clearly wanted them to climb quickly in order to spend as little time as possible in the restricted military area, but why he cleared them to climb through this area at all has never been properly elucidated.
Flight Engineer Kłossek accelerated the engines back to takeoff power for a rapid climb. They appeared to respond normally, and the atmosphere in the cockpit remained relaxed. At 10:40, still climbing to their cruising altitude, the crew reported, “Warsaw radar, LOT 5055, we passed Grudziądz at 10:39. Now passing through level 265, up to 310, estimating Darłowo at 10:53.”
“Okay, thank you, report reaching 310 and squawk 6161,” the controller said.
Radio Operator Bogdan read back the clearance. And then, just seconds after he finished, all hell broke loose.
At the back of the plane, the №2 engine exploded with tremendous force, throwing debris in every direction. Multiple fragments of the low pressure turbine disk ricocheted through the fuselage, breaching the pressure vessel and triggering an explosive decompression. The air rushed out of the cabin, tearing away loose objects with it, and the plane slewed violently downward and to the left.
In the cockpit, the pilots were brought to their senses by the intermittent autopilot disconnect alarm. “Hey! Pressurization!” someone shouted. (The official transcript of cockpit communications does not distinguish who said what.)
“Is there a fire? What is it?” someone asked.
“Probably a fire!”
“In the engine? Shut it down!”
“Shut it down! №1 is on fire!”
Indeed, as so often seemed to happen on the Il-62, the failure of engine №2 had irreparably damaged the adjacent engine №1 as well. Fire alarms in both engines were now blaring, although investigators would later determine that there was no fire — the sensors were instead triggered by hot gases pouring out of the engines’ ruptured combustion chambers.
Meanwhile, the flurry of shouting continued.
“All idle, depressurization…”
“Two engines gone!” The sound of an engine fire alarm blared in the background.
“We’re turning back! Fire!” someone shouted.
“Mayday, Warsaw Radar, Warsaw Radar!” Captain Pawlaczyk announced to air traffic control. “Emergency descent!”
In the background, other pilots continued to shout: “What is — hey!”
“Two engines gone!”
“We have no elevators!” someone exclaimed. Indeed, just like flight 007 before it, flight 5055’s elevator control push rods had been severed by the flying debris, leaving the pilots without the ability to move their primary pitch control surfaces. They were already in an emergency descent, hurtling downward toward breathable air — a major concern on the Il-62, which apparently was not equipped with passenger oxygen masks — but would they be able to pull out at the bottom?
Meanwhile, the controller finally replied: “State your callsign?”
“Two engines hit, two engines shut down!” Pawlaczyk said.
“Is it a collision?” the controller asked.
“We don’t know what happened. Two engines failed. We’re descending,” said Pawlaczyk.
“LOT 5055, roger,” said the controller.
For two minutes the frantic back-and-forth between the pilots continued as they struggled with the multiple simultaneous malfunctions. They had no elevators, no pressurization, and only two of their four engines, but they did have the rudder, and more importantly, they had stabilizer trim. The trimmable horizontal stabilizer is normally used to alter the plane’s stable pitch angle and compensate for changes in the center of gravity; it is not designed for the frequent, small inputs that are needed to actively control the airplane. However, it did allow the pilots to control their pitch, albeit imprecisely, and that was all that was needed to stabilize the descent.
Their next problem, however, was that they were still fully loaded with fuel for the flight to New York, and at such a high gross weight they would be unable to maintain altitude on only two engines. Furthermore, they were well above the maximum landing weight, and if they attempted to touch down, the landing gear could collapse. There was only one solution: to dump as much fuel as possible.
“We will be dumping fuel,” Captain Pawlaczyk reported to air traffic control. “We’re returning to Warsaw. We’re descending out of 5,400 meters, down to 4,000.”
“Roger, will you be dumping here?” the controller asked.
“We’ll be dumping when we’re out of the turn,” said Pawlaczyk.
Descending through 4,000 meters, or 13,200 feet, the pilots began to run through the symptoms of their emergency.
“…[T]here is something with the controls, you know?”
“Yes, we collided with something!”
“Yeah. Something with the controls?
“Because the controls didn’t work for me, but the stabilizer trim works.”
But that wasn’t all: three of the plane’s four electrical generators had failed, two because they were powered by the failed engines, and another was inoperative perhaps due to damage to its relays. “Gentlemen! We’re flying on only one generator,” someone announced.
“What was that?”
“We are on one generator! We need to get rid of unnecessary [electrical load] now.”
“I’m turning off all the unnecessary stuff now!” someone replied.
The pilots and the Flight Engineer began switching off any electrically-powered equipment that they didn’t need. With only one working generator struggling to support all the active systems, there wasn’t enough power to open the Il-62’s electrically actuated fuel jettison valves. By shutting off multiple systems, they managed to get the valves open, but due to damage to electrical wiring in the tail, they only worked intermittently.
This was a big problem, because if they couldn’t bring down their gross weight, they wouldn’t be able to maintain altitude on only two engines. “We’re going lower,” someone pointed out. “Say we’re going down, because we can’t hold [altitude], we can’t keep the speed up and we’re going down.”
“Tell them to direct us to Modlin, and quickly,” someone advised.
Now used as an international hub by low cost carriers like Ryanair, Modlin Airport in 1987 was a military air base run by the Polish Air Force. Located some 33 kilometers northwest of Warsaw, its runway was shorter and its infrastructure was poorer than Warsaw Okęcie Airport, but it had one advantage: it was much closer. If they couldn’t dump enough fuel to maintain altitude, then they had to go to the closest available airport, regardless of its facilities. But the discussion seemed to become sidetracked. “Something must have hit the elevator,” someone said. “It was a hit like…”
“Yes! A hit like hell.”
“LOT 5055,” the controller asked, “Which engines were these? One and two?”
“One and two, but we’re having trouble controlling [the plane] without elevators.”
“I see. Are you maintaining altitude now?” the controller asked.
“NO!” somebody shouted.
Moments later, at 10:50, someone pointed out that they were still 108 nautical miles from Warsaw — a considerable distance given the state of their aircraft.
“Maybe Modlin on the way?” someone suggested again.
“There is no other.”
“Modlin is on the way.”
“Are we requesting Modlin?”
“What’s the runway in Modlin?”
“Long, and perfectly flat!”
“You could, you could go to Modlin,” someone confirmed.
“It would be better if it were longer.”
“But [we] can’t maintain altitude?”
“Currently level 110, ’55,” Pawlaczyk reported to air traffic control.
“Got it, 110. And can you maintain altitude?” the controller asked.
“Well, not really,” said Pawlaczyk.
“We can’t dump the fuel, something’s jammed,” someone exclaimed, probably Flight Engineer Kłossek. “We can’t dump fuel. The valve is jammed. You’re not losing fuel.”
As the flight engineers tried to troubleshoot the issue, one of the pilots said to the Radio Operator, “Ask how far to Modlin and if he can direct us.”
“Warsaw radar, 5055,” Pawlaczyk said. “Can you direct us to Modlin? Because our altitude is constantly falling, it’s getting lower and lower.”
“One moment! I will arrange it,” the controller replied. He couldn’t clear flight 5055 to Modlin himself; because this was a military airfield, he needed to request permission from the Air Force.
While they waited, the pilots again discussed the functioning of the horizontal stabilizer and various electrical buses. But they were still losing altitude, and their attention soon turned back to landing.
“Can you direct us to Modlin?” Pawlaczyk asked again.
“We are waiting for the army’s decision, one second,” said the controller.
“Well, do something, because we are in a really difficult situation,” said Pawlaczyk. “We have to land as soon as possible.”
“5055, everything will be arranged, they are still sorting things out with the army there,” said the controller.
Suddenly, the plane was rocked by another explosion. What was it this time?
“Engine explosion!” someone exclaimed.
“5055, you will land in Modlin,” the controller interjected. “As soon as approach sees you, they’ll guide you.”
The sound of the blast had caused considerable agitation on the flight deck. “The explosion was on the engine!” someone said.
“There’s probably a hole in the fuselage…”
The cockpit voice recorder captured some fragmented lines which may have been a flight attendant reporting to the crew, or one of the crewmembers passing on such a report: “…explosion on it… but sparks in the back of the plane…”
But when the pilots looked at their instruments, they still had two functional engines — no further failures had occurred. This seemed to calm them down. They had no idea that they were actually dealing with something much worse than another engine failure.
In fact, unbeknownst to the crew, one of the engine fragments, heated to a temperature of 700˚C, had penetrated the fuselage and lodged inside the aft baggage compartment, starting a fire. This blaze had been burning since the moment of the engine failure more than 12 minutes earlier, but the fire alarm which should have warned the crew never went off, probably because the wires connecting it to the cockpit had been cut. It is thought that the explosion at 10:53 may have been the result of the fire breaching the wall of the baggage compartment, where it ignited vapors which had leaked from a damaged fuel line connecting the tail fuel tank to the wing tanks.
Still unaware of the fire, however, the pilots spent several minutes preparing to land with Modlin, which lay some distance ahead on the north bank of the Vistula River.
At 10:58, the crew were transferred back to Warsaw approach control. “Current altitude is 085, still descending,” Pawlaczyk reported. “We can’t maintain altitude and we’re heading towards Modlin.”
“Roger,” said the controller. “Please maintain current heading, descend to 650 meters. The pressure at Okęcie is 749 for now. The runway in Modlin is 3,050 meters long. You’ll be landing on a heading of 262.”
“We will try,” someone said.
“Okay, to 650 meters, direction at Modlin 262, please direct us there,” said Pawlaczyk.
“And he can’t, because it’s closed,” someone commented.
“I’m trying to get you guys in,” said the controller. “I don’t know where the runway threshold is. We just need to figure out what the wind direction is, what the pressure is. No data available yet. All I know is that the length of the runway is 3,050 meters.”
At this point they were still coming in from the west, but the controller was planning to have them land at Modlin from the east, so they could land into the wind. Apparently the stated runway length was insufficient to allow them to land from the west with a tailwind.
“Well, we can’t land with the wind!” someone said.
Then someone else brought up the fact that at their current weight, the gear might collapse on landing. And one of the flight engineers noted that they had managed to dump a considerable amount of fuel, allowing them to finally maintain altitude on two engines. It was at that point that someone uttered a potentially fateful suggestion: “Wouldn’t it be better to fly to Warsaw?”
“Do we land here?”
“Isn’t it better in Warsaw?”
“It would be better in Warsaw, because there’s…”
“Because there, you know, the equipment is better.”
“I know, but…”
“Probably better in Warsaw.”
“I would fly to Warsaw,” someone agreed.
“I would also fly to Warsaw.”
“Come down slowly,” someone said. “I will tell him that we’re flying to Warsaw.”
And so it was decided. They wouldn’t fly to Modlin after all — they would extend the flight by a few minutes and land back at Okęcie instead.
“LOT 5055, we’ve made a decision, we will fly to Warsaw,” Captain Pawlaczyk reported. “In Warsaw, the equipment will be better for us.”
“Roger,” said the controller.
The pilots now faced a question: should they make a simple right turn and land straight in on runway 15 with a tailwind, or circle around from the south to land on runway 33, which would be safer, due to the headwind?
“Straight in?” someone asked.
“No! There will be too much wind,” someone replied. They were worried about the tailwind, which was blowing out of the northwest at 22 km/h.
The controller again cleared them down to 650 meters, reporting that “there is nothing underneath you.”
“Thank you,” said flight 5055. “Except, there is a possibility that we will crash land, because we have problems with everything here, electricity and everything. If the landing gear doesn’t come out, the fuselage is damaged, if the landing gear and flaps, as they’re called, don’t come out, then we’ll have to crash land.”
“Roger,” said the controller.
“And for the record, we don’t have elevator controls,” Pawlaczyk repeated.
Over the next several minutes, the pilots worked hard to navigate to the south of the airport in preparation for the approach, all the while struggling to balance their unstable altitude and speed using their imprecise pitch controls. For a while, it seemed like the situation was relatively under control. But then, at 11:08, they received the first of several pieces of bad news. As the flight attendants worked to prepare the cabin for the emergency landing, they apparently discovered that stewardess Hanna Chęcińska was nowhere to be found.
“There’s no Hanna, huh!?” someone reported.
“Where is, actually…”
“One stewardess is missing, because the door has been ripped off,” someone said, implying that Ms. Chęcińska may well have been ejected from the airplane. After all, she was stationed in the very rear of the plane, near the area that was damaged during the engine failure.
Then, just 15 seconds later, an alarm burst to life, warning of a fire in the cargo hold. The blaze had in fact been burning for 27 minutes, but it had only now begun spread into an area with a working smoke detector.
“We have a fire!” someone exclaimed.
“We are burning!”
Now the pilots were growing desperate. “Where is the airport? Where?”
“We’re landing with a fire!”
“Where is the airport? Which side is the airport on? Hey!”
The pilots breathlessly reported the fire to the air traffic controller, who offered them a shortcut to the runway. Moments later, flight 5055 began an awkward base turn at close range, just a few kilometers south of runway 33. From that point on, however, the situation became hopeless, and the timeline becomes murkier. At 11:09, both black boxes ceased recording, apparently having been severed from their sensors by the rapidly spreading fire. Among the last sounds captured on the cockpit voice recorder were the words, “Wait! Don’t panic!”
From then on, only the pilots’ radio calls were recorded, growing in desperation with every passing moment.
“From this position you have 15 kilometers to the runway,” the controller reported.
“I see it,” said flight 5055. In the background, someone shouted “Left! Engines to the left!”
“5055, left 050,” the controller said, guiding the flight through its final turn.
“5055, left heading 360.”
“Begin your final descent eleven kilometers from the runway,” the controller said.
“We will do everything we can,” the flight ominously replied.
“Roger. Left heading 320.”
But flight 5055 was overshooting its final turn. “You crossed the right side of the runway centerline, then left on heading 300,” the controller said, trying to get them back on track. “The wind is 290 degrees, 22 km/h, you can land runway 33.”
“Okay,” said Pawlaczyk.
Seconds later, at 11:12 and 10 seconds, something snapped at the back of the plane, and flight 5055 pitched abruptly downward. Someone pressed the microphone key four times, broadcasting several unintelligible shouts and screams. And then, three seconds later, someone yelled, “Goodnight! Goodbye!” There was another scream, and then a voice added, “Bye! We’re dying!”
And with a terrible roar, LOT Polish Airlines flight 5055 plowed headlong into the pines of the Kabaty forest, pitched 12 degrees nose down, banked 11 degrees to the left, and traveling at a speed of 465 kilometers per hour. The Il-62 mowed down a vast swath of trees and then struck the ground with tremendous force, disintegrating utterly in an enormous fireball. Within seconds, it was over — nothing remained.
Although all manner of rescue and firefighting personnel rushed to the scene of the fiery crash, they quickly discovered that there was no one to save. Body parts lay strewn through the forest, mixed in with burning debris and mangled chunks of metal, scarcely recognizable as an airplane. None of the 183 people on board had survived, making the crash of LOT flight 5055 by far the worst air disaster in Polish history.
Later, the cleanup of the site was marred by accusations of looting, either by bystanders or military personnel, although these claims were never substantiated. Furthermore, many of the victims’ families never received any remains, because only 121 of the 183 passengers and crew were ever identified. Among those listed as missing was Hanna Chęcińska, adding to the speculation that she may have been sucked out of the plane during the explosive decompression. When investigators returned to the site of the original engine failure to look for missing components, they also searched for her body, but while the engine parts were eventually found, Ms. Chęcińska was not. As a result, the prevailing theory holds that since she was stationed inside the technical bay in between the two sets of engines, she may have been killed instantly by flying debris. In any case, the fact that she was not found does not necessarily support the conclusion that she was sucked out, given that 61 other passengers and crewmembers also remained unidentified.
Immediately after the crash, the government of Poland set up an investigative commission led by high-ranking aviation officials supported by an army of technical experts. These experts managed to recover the missing portions of engine №2 in the countryside near Grudziądz, where they had fallen from an altitude of 8,200 m (27,000 feet). Upon examination, these components told a surprisingly familiar story. In fact, just as in the case of LOT flight 007 in 1980, the low pressure turbine shaft had snapped in two, causing the LP turbine disk to overspeed until it ripped itself apart in less than two tenths of a second. Fragments of the turbine disk, heated to 700˚C and traveling at 160 meters per second, flew outward in all directions. Once again, one of them struck and disabled the adjacent №1 engine. A second fragment penetrated the left side of the fuselage, sliced through several bundles of electrical wires, and continued out the other side. And a third fragment entered the fuselage near the floor line, cut through the elevator control push rods, and lodged in the aft baggage compartment, where it started a fire.
Once the fire started, the baggage compartment was not fire-resistant in any way. Not only was it full of passengers’ luggage, which contained large amounts of duty-free alcohol, the floor of the compartment itself was literally made out of wood. These materials fueled the fire until it eventually burst out of the baggage compartment, where it may have been accelerated by leaking fuel. Finally, near the end of the flight, it almost certainly contributed to the pilots’ ultimate loss of control. The exact sequence of events could not be established, but three hypotheses were put forward: A), that the fire melted the plastic brackets holding the stabilizer control rods in place, leading to a total loss of pitch control; B) that the fire weakened the aft fuselage structure, causing it to bend in such a way that it imparted an uncontrollable nose-down moment; or C), that the fire burst through the floor and into the aft passenger cabin, causing passengers to flee to the front of the plane. This shift in center of gravity would have caused the plane to pitch down, and there may have been insufficient time for the pilots to compensate by cranking the stabilizer nose up.
In any case, attempting to pick one explanation over the others would have been purely speculative. The official report, for its part, simply said that the fire caused the loss of control without attempting to explain why.
The fact that flight 5055 flew for a total of 31 minutes after the engine failure before crashing just 40 seconds short of the airport raised questions about whether the pilots could have landed sooner. The brief official report noted that the decision to switch from Modlin to Warsaw likely added about eight minutes of flight time, which certainly could have meant the difference between life and death. In fact, while the report did not directly criticize the pilots’ decision making, it did state that a landing at Modlin or a straight-in landing with a tailwind on runway 15 at Okęcie would have been “unobjectionable,” while circling around to land from the south on runway 33 had both “advantages and disadvantages.” The disadvantages included increased flight time and the necessity to carry out additional maneuvers with damaged flight controls. The advantages were expressed by the pilots themselves on the cockpit voice recording: the runway was longer than at Modlin, the weather was a known quantity, and the pilots believed the airport to have better firefighting capabilities. This latter point seemed to be most important to them, given that their imprecise controls, excess weight, and large fuel load could have led to a fiery crash landing.
Most critically, however, the pilots were unaware that their airplane was already on fire. Due to the interruption of the fire alarm circuit, they were not warned of the fire in the aft baggage compartment until shortly before the end of the flight, at which point landing on runway 33 was the only possibility. Had they been informed of the fire earlier, the pilots probably would have sought to land at the nearest available airport, which would have been Modlin. Instead, once they had dumped enough fuel to maintain altitude, the pilots believed that the situation had stabilized and that they had time to proceed to a larger, better-equipped airfield. This fateful decision may well have cost them their lives, but it’s difficult to fault them for what appeared to be a cautious choice made under pressure.
But all of this analysis hinged on a crucial question: why did the №2 LP turbine shaft fail in the first place? The answer was not as straightforward as it was in the case of flight 007. In that accident, metal fatigue of the shaft had led to its failure, but this time, there was no evidence of fatigue — instead, the shaft had broken after the material was made brittle by a prolonged period of overheating, the source of which was apparently the mid-shaft roller bearing.
On the Soloviev D-30 engine, like the Kuznetsov NK-8 engines which preceded it, the low-pressure turbine shaft rotated inside of the shorter but wider high-pressure turbine shaft. These shafts rotated at substantially different speeds — the LP shaft at 4,750 rpm, and the HP shaft at 10,520 rpm, according to one source, which did not specify whether these numbers were true at all power settings. In any case, to prevent the two shafts from coming into contact, structural rigidity was provided by a dual-race roller bearing mounted at the midpoint of the two shafts. Each race consisted of a ring containing several cylindrical rollers, which transferred rotational energy of the shaft into the bearing structure. The inner race was mounted to the exterior of the LP shaft and the outer race to the interior of the HP shaft, allowing the two races to rotate at different speeds while providing continuous support to both shafts.
According to the official investigation, the reason that the LP turbine shaft overheated was because the mid-shaft dual-race roller bearing suffered from excessive wear, until unspecified “shaft elements” began to contact one another, generating heat from friction. This heat eventually weakened the shaft until it failed. However, after examining multiple sources, there does not appear to be a single, consistent explanation for why the mid-shaft roller bearing wore down prematurely, as the engine was within the 3,000 hour limit between scheduled overhauls.
The official accident report does not explain the cause of the wear and does not specify whether the bearing was properly manufactured. However, additional sources broadly agree that the bearing was manufactured with only half the intended number of rollers — 13, rather than 26 — but they disagree as to why. According to one source which appears to have had access to primary documents, the 26-roller configuration was found to suffer from excessive friction, either in service or in testing, so the number was halved to 13 in order to reduce the total contact area between the rollers and the bearing housing. This was said to have been done without the approval of the engine designers, which was possible in the Soviet Union because the design, manufacturing, and testing phases for aerospace equipment, including airplanes and engines, were performed by separate state-run organizations. It is therefore entirely plausible that the factory could have decided to install 13 rollers instead of 26 without the approval or knowledge of the engineers who designed the bearing.
According to this version, the use of fewer rollers meant that each roller was subject to greater wear, so several holes were drilled in the inner race to allow more lubricating oil to enter. However, the forces applied to the bearing caused these holes to develop fatigue cracks, which eventually led to loss of material around the holes. Subsequently, on the accident flight, a roller briefly became lodged in one of these holes, jamming the inner race. As a result, the rollers in the inner race began sliding rather than rolling, generating intense frictional heating of the bearing. This condition persisted for several minutes as flight 5055 climbed at high power toward 31,000 feet, following the controller’s instruction to expedite the climb. During this time, the temperature of the bearing increased to over 1,000˚C. Eventually, the structural integrity of the LP shaft was compromised to such an extent that it broke, freeing the LP turbine disk. Finally, the disk oversped and tore itself apart.
However, the most commonly repeated version of the story holds that the number of rollers was reduced from 26 to 13 because the factory didn’t receive its shipment of rollers on time, and management didn’t want to delay the delivery of the engines. Despite the prevalence of this theory, my research was unable to find any supporting evidence. This version appears to have been written into commonly referenced sources, such as Wikipedia, without any verifiable citations, and I did not find any credible sources which even acknowledged the existence of the “late delivery” theory, let alone corroborated it. Such things did happen in the Soviet Union, but my suspicion is that the story of the late delivery might have started out as speculation which somehow mutated into accepted fact.
That having been said, a significant percentage of all the known information about the crash is inherently unverifiable, for the reasons given in the preface to this article. Although an official report on the crash of flight 5055 was made available to the public, it was exceptionally brief and provided little in the way of useful information. Much of this article is therefore based on news articles by journalists who claim to have seen documents related to the two crashes in Poland’s national archives, and not on the primary documents themselves.
According to many of the aforementioned sources, the findings of the Polish investigation caused consternation in the Soviet Union, whose officials were not keen on acknowledging a conclusion which implied that poor Soviet workmanship was once again responsible for a Polish air disaster. Although Soviet engineers acknowledged privately that a manufacturing defect was to blame, higher-ranking Soviet officials objected, issuing a 79-page rebuttal — significantly longer than the accident report itself — which argued that the damage to the roller bearings was a result of the crash and not its cause. The Soviet side also contended that the bearings were shipped in a condition which fully corresponded to the manufacturer’s documentation, and that excessive wear on the roller bearings would have resulted in heavy vibrations well before reaching the point of failure. Therefore, they argued, if this issue was in fact the cause, then LOT could only have failed to detect it if the plane was dispatched with an inoperative №2 engine vibration gauge.
For their part, the Polish investigators noted that contrary to the manufacturer’s assertions, the engine did not vibrate excessively until mere seconds before its failure, a fact which was revealed in the recorded flight data. An inspection of other Soloviev D-30 engines in service in Poland also revealed the presence of additional worn mid-shaft roller bearings in engines which had yet to complete their 3,000-hour service life between overhauls. Furthermore, in their view, this wear could only have been detected during these overhauls, and not by LOT in the course of routine servicing. The Deputy Prime Minister of Poland even submitted an official letter of protest, pointing out that the Soviet Union’s own technical experts, who had participated throughout the investigation, agreed with Poland’s version of the probable cause.
Then, in October 1987, another Soloviev D-30 engine in service on a LOT Tupolev Tu-154 suffered a major failure despite having accumulated only 2,100 hours in service. (The source for this information did not specify the type of failure, or any other details.) At that point, the Soviet Union apparently reversed course, for the first time acknowledging that poor workmanship had contributed to both Il-62 crashes. Consequently, Ilyushin ordered the inspection and replacement of the mid-shaft roller bearings on all Il-62 engines; designed and installed a redundant set of flight control connections; and developed a better vibration gauge which would give more advance warning before a catastrophic failure. In addition, the Polish investigators recommended that Ilyushin remove flammable materials such as wood from the baggage compartments and improve the Il-62’s in-flight firefighting capabilities.
In the end, LOT Polish Airlines didn’t operate the Il-62 for very much longer. Just two years after the crash of flight 5055, Poland’s Soviet-aligned government was overthrown amid the revolutions of 1989, leading to a geopolitical realignment. That same year, LOT purchased Western aircraft for the first time since the 1950s, replacing its Il-62s with brand new wide body Boeing 767s. The airline was pleased to note that the 767’s General Electric CF-6 engines did not feature turbine shafts with an internal bearing.
Looking back, the twin disasters on board LOT flights 007 and 5055 present a classic example of the particular shortfalls of air safety behind the Iron Curtain. The West has had plenty of repeat disasters caused by the same basic, uncorrected design flaws, but the way in which such linked tragedies came about differed depending on location. In the United States, there is no shortage of investigative curiosity and official transparency, but the government often lacks the ability and willingness to confront powerful corporations which cut corners in the interest of profit. On the other hand, in the now-vanished East, there were no corporations seeking to protect their profits, but because there was no clear dividing line between the aviation industry and the state apparatus, questions about safety were often seen as undermining the credibility of the state. Consequently, there were strong political incentives to avoid revealing any information which might prompt public backlash, which in turn made it much easier for state enterprises to ignore known problems, such as poor workmanship in Il-62 engines or a lack of control system redundancy.
Nevertheless, in the face of so much secrecy and uncertainty, the Polish people did not easily forget the disaster in the Kabaty woods. A prominent memorial now stands at the crash site, and the story of flight 5055 has been revisited in numerous news articles, documentaries, and online discussions. It also holds a special place in the hearts of Polish pilots, who above all respect the heroism and grit of Captain Zygmunt Pawlaczyk, First Officer Leopold Karcher, and all the other pilots and cabin crew members who fought for 31 minutes to save the lives of their passengers. Former Il-62 pilot Tomasz Smolicz perhaps put it best: “All air routes from Warsaw to America lead over Grudziądz,” he wrote. “And there, among all crews, silence falls. Voices fall quiet and the eyes of the pilots follow the instruments in concentration. It’s as if the plane passes through a strange cloud of sadness, as if in a familiar cemetery, as if at the roll call of the fallen at the foot of an invisible monument.” To his poetic conclusion we might add that the cloud of sadness emerges not only from the great loss of life, but from its frustrating, almost banal preventability. How tragic it seems that lightning had to strike twice before the thunder was heard.
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