When All Engines Fail

If you recall your first time on an airplane you may have wondered how such a heavy steel construction can sustain flight with just one propeller or a few jet engines. Such is the marvel that is flight, but what happens when the unthinkable happens? What happens when all engines fail?

First of all it’s important to note that it is exceptionally rare for multiple engines to fail mid-flight. Even if this rarity does occur, all pilots are trained to restart, relight in aviation parlance, a plane’s engines mid-flight. Even if a relight is unsuccessful, airplanes do not just drop out of the sky. Much like gliders which operate without engines, all airplanes are capable of gliding for considerable distances, depending on multiple factors including altitude and speed, thus allowing the pilot to perform a relative safe landing. In this kind of situation it is perfectly normal for a pilot to request to land on the longest available runway. If the plane is unable to glide to the safety of an airport runway, pilots are able to land on major highways, grassy planes or even water with few or no fatalities. The men and women who pilot commercial aircrafts receive rigorous training on all possible emergency scenarios and as such are able to deal with most anticipated emergency scenarios.

That said, there have been some notable aviation emergencies and disasters attributed to the rare but obviously possible scenario of multiple engine failure. Only recently the Honourable Minister of Aviation, Princess Stella Oduah, alluded to the possibility that the MD-83 that operated Dana Air Flight 992 may have been a victim of dual engine failure.

Whilst it’s too early to speculate on the exact cause of the plane crash, I would like to consider what factors could possibly lead to multiple, or in the case of Dana Air Flight 9j-992, dual engine failure.

Empirical evidence suggests that multiple engine failure caused by mechanical faults is essentially unknown in the aviation industry. Moreover, empirical evidence also suggests that when multiple engine failure does occur it is usually as a result of external factors including but not necessarily limited to volcanic ash, ice or water ingestion, heavy rain-bearing clouds at low altitudes, massive bird strikes, fuel exhaustion or contaminated fuel.

In 1977, a McDonnell Douglas DC-9 operated by Southern Airways, an American airline, was forced to perform a forced landing after experiencing Dual engine failure due to water and hail ingestion whilst flying through a severe thunderstorm. The crew unsuccessfully attempted to relight the engines. With no airports or air strips within reach and altitude declining quickly, the pilot made a forced landing on a straight section of rural highway. 72 fatalities were recorded including 9 on ground.

In 1982, a Boeing 747-236B operated by British Airways headed to Aukland, Australia flew into a cloud of volcanic ash thrown up by the eruption of Mount Hualunggung near Jakarta.  All four engines failed. The aircraft was able to glide far enough to exit the volcanic ash cloud thus allowing the pilots to safely relight all engines. The pilots landed in Jakarta. No fatalities were recorded.

In 1983, United Airlines flight 310 operated by a Boeing 767-222 experienced dual engine failure over the Arapahoe National Forest west of Denver, Colorado. The National Transportation Safety Board (NTSB) of America concluded that dual engine failure occurred as a result of fuel system and nozzle contamination. The crew were able to relight the engines at approximately 15,000 feet and subsequently landed safely in Denver. Zero fatalities were recorded.

In 1991 an MD-80 operated by Scandinavian Airlines performed a crash landing just four minutes into the flight. There were no fatalities. The plane’s engines ingested ice causing surging. Investigations revealed that when the flight captain tried to clear the surge by throttling back the planes on-board systems increased thrust until the engines destroyed themselves.

Many of you will also recall the sensational emergency landing of US Airways Flight 1549 on the Hudson River in New jersey in 2009. Preliminary investigations by the NTSB suggested that the aircraft, an Airbus A320-214, may have experienced complete engine failure as a result of a massive bird strike. There were no fatalities. The NTSB subsequently concluded in its final report that probably cause of the incident to be “the ingestion of large birds into each engine, which resulted in an almost total loss of thrust in both engines.” The flight captain, Captain Sullenberger, a former fighter pilot and his entire crew were awarded a ‘Masters Medal’ by the Guild of Air Pilots and Air Navigators - an accolade awarded only rarely, for outstanding aviation achievements.

The few cases reviewed seem to support the initial theory that multiple or complete engine failure is most probably caused by external, non-mechanical related issues. Though its too soon to authoritatively state the exact cause of the Dana Air Flight 992 incident, the case studies available in the public domain seem to suggest that if what was alluded to by the Honourable Minister is indeed the case, then the investigators should most certainly be open to the possibility of non-mechanical related causes of engine failure.

This would also mean that other areas of speculation such as inadequate maintenance or human error may not necessarily be the primary cause of the plane crash that claimed the lives so many. It also suggests that the relevant authorities may also need to review other factors that may have also contributed to the overall number of fatalities including things such as flight path, airport location and emergency services response speed.

Only one thing is certain though - the families have lost loved ones and will grieve for a long time and as such require full and final closure in the form of speedy and thorough investigations by the bodies mandated to investigate the incident by law. These bodies include the Accident Investigation Bureau, the Nigerian Civil Aviation Authority and the Ministry of Aviation. One can only hope that investigations are swift and that the final report goes towards ensuring that we never experience another deeply saddening and troubling incident like this.

Edet Akpan, an engineer, writes from Uyo.