after it experienced catastrophic uncontained compressor rotor failure in 1996. Engine failures may be classified as either as "contained" or "uncontained". • A contained engine failure is one in which all internal rotating components remain within or embedded in the engine's case (including any containment wrapping that is part of the engine), or exit the engine through the tail pipe or air inlet. • An uncontained engine event occurs when an engine failure results in fragments of rotating engine parts penetrating and escaping through the engine case. The very specific technical distinction between a contained and uncontained engine failure derives from regulatory requirements for design, testing, and certification of aircraft engines under Part 33 of the US
Federal Aviation Regulations, which has always required turbine aircraft engines to be designed to contain damage resulting from rotor blade failure. Blade fragments exiting the inlet or exhaust can still pose a hazard to the aircraft, and this should be considered by the aircraft designers. Engine cases are not designed to contain failed turbine disks. Instead, the risk of uncontained disk failure is mitigated by designating disks as safety-critical parts, defined as the parts of an engine whose failure is likely to present a direct hazard to the aircraft. • Two
LOT Polish Airlines flights, both
Ilyushin Il-62s, suffered catastrophic uncontained engine failures in the 1980s. The first was in 1980 on
LOT Polish Airlines Flight 7 where flight controls were destroyed, killing all 87 on board. In 1987, on
LOT Polish Airlines Flight 5055, the failure of the aircraft's inner left (#2) engine damaged the outer left (#1) engine, setting both on fire and causing loss of flight controls, leading to a crash that killed all 183 people on board. In both cases, the turbine shaft in engine #2 disintegrated due to production defects in the engines' bearings, which were missing rollers. • The
Tu-154 crash near Krasnoyarsk was a major aircraft crash that occurred on Sunday, 23 December 1984, in the vicinity of Krasnoyarsk. The Tu-154B-2 airliner of the 1st Krasnoyarsk united aviation unit (Aeroflot) performed passenger flight SU-3519 on the Krasnoyarsk-Irkutsk route, but during the climb, engine No. 3 failed. The crew decided to return to the airport of departure, but during the landing approach a fire broke out, which destroyed the control systems and as a result, the plane crashed to the ground 3200 meters from the threshold of the runway of the Yemelyanovo airport and collapsed. Of the 111 people on board (104 passengers and 7 crew members), one survived. The cause of the catastrophe was the destruction of the disk of the first stage of the low pressure circuit of engine No. 3, which occurred due to the presence of fatigue cracks. The cracks were caused by a manufacturing defect – the inclusion of a titanium-nitrogen compound that has a higher microhardness than the original material. The methods used at that time for the manufacture and repair of disks, as well as the means of control, were found to be partially obsolete, which is why they did not ensure the effectiveness of control and detection of such a defect. The defect itself arose probably due to accidental ingestion of a titanium sponge or charge for smelting an ingot of a piece enriched with nitrogen. •
Cameroon Airlines Flight 786: a
Boeing 737 flying between Douala and Garoua, Cameroon in 1984 had a failure of a
Pratt & Whitney JT8D-15 engine. Two people died. •
British Airtours Flight 28M: a Boeing 737 flying from Manchester to Corfu in 1985 suffered an uncontained engine failure and fire on takeoff. The takeoff was aborted and the plane turned onto a taxiway and began evacuating. Fifty-five passengers and crew were unable to escape and died of smoke inhalation. The accident led to major changes to improve the survivability of aircraft evacuations. •
United Airlines Flight 232: a
McDonnell Douglas DC-10 flying from Denver to Chicago in 1989. The failure of the rear
General Electric CF6-6 engine caused the loss of all hydraulics, forcing the pilots to attempt a landing using
differential thrust. There were 111 fatalities. Prior to this crash, the probability of a simultaneous failure of all three hydraulic systems was considered as low as one in a billion. However,
statistical models did not account for the position of the number-two engine, mounted at the tail close to hydraulic lines, nor the results of fragments released in many directions. Since then, aircraft engine designs have focused on keeping shrapnel from puncturing the
cowling or ductwork, increasingly using high-strength
composite materials to achieve penetration resistance while keeping the weight low. •
Baikal Airlines Flight 130: a starter of engine No. 2 on a
Tu-154 heading from
Irkutsk to
Domodedovo, Moscow in 1994, failed to stop after engine startup and continued to operate at over 40,000 rpm with open bleed valves from engines, which caused an uncontained failure of the starter. A detached turbine disk damaged fuel and oil supply lines (which caused fire) and hydraulic lines. The fire-extinguishing system failed to stop the fire, and the plane diverted back to Irkutsk. However, due to loss of hydraulic pressure the crew lost control of the plane, which subsequently crashed into a dairy farm killing all 124 on board and one on the ground. • ValuJet Flight 596: A
DC-9-32 taking off from
Hartsfield Jackson Atlanta International Airport on 8 June 1995, suffered an uncontained engine failure of the 7th stage high pressure compressor disk due to inadequate inspection of the corroded disk. The resulting rupture caused jet fuel to flow into the cabin and ignite, and the fire caused the jet to be a write-off. •
Delta Air Lines Flight 1288: a
McDonnell Douglas MD-88 flying from Pensacola, Florida to Atlanta in 1996 had a cracked compressor rotor hub failure on one of its
Pratt & Whitney JT8D-219 engines. Two died. •
TAM Flight 9755: a
Fokker 100, departing
Recife/Guararapes–Gilberto Freyre International Airport for
São Paulo/Guarulhos International Airport on 15 September 2001, suffered an uncontained engine failure (Rolls-Royce RB.183 Tay) in which fragments of the engine shattered three cabin windows, causing decompression and pulling a passenger partly out of the plane. Another passenger held the passenger in until the aircraft landed, but the passenger blown out of the window died. •
Qantas Flight 32: an
Airbus A380 flying from London Heathrow to Sydney (via Singapore) in 2010 had an uncontained failure in a
Rolls-Royce Trent 900 engine. The failure was found to have been caused by a misaligned counter bore within a stub oil pipe leading to a fatigue fracture. This in turn led to an oil leakage followed by an oil fire in the engine. The fire led to the release of the Intermediate Pressure Turbine (IPT) disc. The airplane, however, landed safely. This led to the grounding of the entire Qantas A380 fleet. •
British Airways Flight 2276: a
Boeing 777-200ER flying from Las Vegas to London in 2015 suffered an uncontained engine failure on its #1
GE90 engine during takeoff, resulting in a large fire on its port side. The aircraft successfully aborted takeoff and the plane was evacuated with no fatalities. •
American Airlines Flight 383: a
Boeing 767-300ER flying from Chicago to Miami in 2016 suffered an uncontained engine failure on its #2 engine (General Electric CF6) during takeoff resulting in a large fire which destroyed the outer right wing. The aircraft aborted takeoff and was evacuated with 21 minor injuries, but no fatalities. •
Air France Flight 66: an
Airbus A380, registration F-HPJE performing flight from Paris, France, to Los Angeles, United States, was en route about southeast of Nuuk, Greenland, when it suffered a catastrophic engine failure in 2017 (General Electric / Pratt & Whitney Engine Alliance GP7000). The crew descended the aircraft and diverted to
Goose Bay, Canada, for a safe landing about two hours later. ==References==