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Accident reviews on this page:

Beech C90
Boeing 737-200
Boeing 747
BN-2
Cessna 310
Cessna 404
DHC-6 Twin Otter
EMB-120ER
Jetstream 4100
Lockheed C-130H
Cessna 404
Mitsubishi MU-2B
Piper PA-31
Piper PA-31P
Piper PA 44-180
Saab SF-340B

On another page:

DC-10 Faro

Engine Failure Related Accidents

Accidents after engine failure continue to happen. A list with more than 395 reported accidents with multi-engine airplanes since Jan. 1996 can be downloaded here; more than 3,600 people lost their lives during these unnecessary accidents.  Unnecessary? Yes, most of them definitely, because if pilots would have been made aware of the limitations that apply for controlling their airplanes while an engine is inoperative and the power setting of the remaining engine is high,  these accidents would not have happened.

Regrettably, flight manuals of most multi-engine airplanes and courseware for a multi-engine rating present definitions of the minimum control speed VMC(A) and engine emergency procedures that are not in agreement anymore with airplane design methods and flight-test techniques.

AvioConsult reviewed more than 300 accident investigation reports and concluded that none of them presented the real cause of the accidents and hence did not recommend the appropriate improvements to really improve aviation safety, see below.  It became clear that neither the mishap pilots nor the accident investigators and in some cases not even the writers of airplane flight manuals and courseware knew about the real value and the limitations of air minimum control speed VMCA (and of takeoff safety speed V2) for the controllability and performance of their airplane following an engine failure or while an engine was inoperative.  A number of training manuals were also reviewed and are also briefly discussed. 

The sole purpose of publishing the comments below is to help prevent accidents after engine failure from happening again.  Please feel free to read or download and learn from these comments.  Please do not hesitate to ask any questions remaining.
All of the theory that is needed to understand the comments presented below can be found in the Paper Airplane Control and Accident Investigation after Engine Failure by AvioConsult. Please refer to the Downloads page.
Formal FAA and EASA documents, a Test Pilot learning manual and references to Aeronautical Universities can be found in the References table on the Downloads page.

On the Downloads page, free papers explaining the controllability and performance while one of the engines of a multi-engine airplane is inoperative are presented, as well as a link to an interesting on-line One Engine Inoperative Trainer of the University of North Dakota. Click here for direct access to this trainer.

Please read the copyright and liability disclaimers here first. 
Unless specifically stated otherwise, you may download one copy of the content for informational, non-commercial and personal use only, provided you keep intact all copyright notices and do not modify the content. 


Reviews of accident investigation reports

A limited number of investigation reports were reviewed by AvioConsult. Please refer to the links in the list in the left column, or browse further down.

If you would like an accident to be reviewed, please don't hesitate to ask.

If you would like to learn how to control an airplane after engine failure, or how to analyze engine failure related accidents using Flight Data Recorder data, click here.


Britten Norman BN-2, Bonaire 22 Oct. 2009

A BN-2 ditched very close to the destination island Bonaire (Caribean) following an engine failure shortly after takeoff from Curaçao.  The passengers could escape and were rescued; the pilot regrettably died in the accident. The accident investigation was conducted by the Dutch Safety Board.
It seems that the pilot was never made aware of the technique to achieve maximum performance (minimum drag) while one engine is inoperative, most probably because neither his training manuals, nor the BN-2 flight manual did provide this life-saving information. The accident investigators were obviously not aware of this either. Refer to the Downloads page for papers on this subject. 

The accident investigation report with many comments, written by AvioConsult using experimental flight-test expertise, is available for download:

Download the Safety Board Report with comments of AvioConsult     |   TOP


Lockheed C-130H, Netherlands 15 July 1996

A C-130H Hercules crashed at Eindhoven Airbase in the Netherlands following the failure of engines #1 and #2 due to bird ingestion during a go-around that was initiated just prior to touchdown. Engine #3 was was shutdown by the crew, either before the approach or just before #1 and #2 failed.
The go-around was initiated at an airspeed below 97 kt, which is far below the flight manual required go-around airspeed of VMCA2 (134 kt in this case). The flight manual requires acceleration to VMCA2 (VMCA for n - 2) before selecting full go-around power to be able to maintain control and in anticipation of another engine to fail on the same wing. If two engines fail on the same wing and the power setting on the other engines is high, the airplane will be uncontrollable at speeds below VMCA2.
In this case, the airplane lost the thrust of three engines (# 1, 2 and 3). Only #4 was operating at max. thrust following the bird ingestion. In this very special case, the actual minimum control speed, however, was VMCA1 (one asymetrical outboard engine). As the airspeed was a little below VMCA1, the airplane started to slowly roll and slide away in a direction away from the operating engine, until it impacted the ground.

The pilots of the airplane and the accident investigators did not know about the real value of the minimum control speeds of the airplane, not about the factors that influence VMCA, not how the magnitude of VMCA can be 'controlled' by the pilots and not what VMCA really means for the controllability and safety of flight before and after engine failure, despite the fact that Lockheed provided good VMCA data and explanations, including control limitations, in the airplane flight manual as well as in a very good publication 'C-130 low speed flying qualities' that is available to all C-130 pilots.

The Flight and Performance Manuals of the C-130H airplane present numerous warnings, cautions and notes on propulsion system malfunctions, explain the reduced controllability after engine failure and present recommended flight techniques and the consequences if these are not adhered to. Lockheed did a good job, but the warnings, cautions and notes are regrettably not understood by most pilots.

Cause of the accident
The cause of the accident was that the pilots were not (made) aware of the go-around speed warnings in the Flight Manual. They initiated a go-around at a speed 37 knots(!) below the Flight Manual required go-around speed when an engine fails or is inoperative.
The Dutch Aviation Safety Board refused to re-investigate the accident following the publication of a book on the accident, at the request of the survivors and relatives of the victims (2010).

Download the analysis of the accident (Dutch language) here    |    TOP


Cessna 404, Australia 11 Aug. 2003

Shortly after liftoff, while still over the runway, the right engine failed. The pilot retracted the landing gear, selected flaps up and feathered the right propeller and then, at very low altitude, turned left, into the operating engine, to return for landing. One of the conclusions in the report was: The aircraft was manoeuvred, including turns and banks, at low altitude resulting in a decrease in airspeed below that required to maximise one-engine inoperative performance.
While on the left hand downwind leg, the airspeed decayed, the altitude could not be maintained and the airplane descended and impacted with the ground. Weight and cg were within limits.

Cause of the accident
The pilot did not maintain 5 degrees of bank after engine failure as required in step 6 in the engine failure procedure in the flight manual, but initiated a turn at too low an altitude (100 ft AGL) while the airspeed was too low. Control was not lost immediately, because the turn was in the direction of the operating engine, which is the favorable direction for keeping actual VMCA low, i.e. below the published VMCA.

The accident investigation report did not include the effect of bank angle on VMCA and the necessity for a 5 degree bank angle into the good engine as a life-saving factor that influences both the controllability and the one engine inoperative climb performance. Pilot and accident investigators were obviously not familiar with the effect of bank angle on both VMCA and the airplane performance, may be because it was never taught to them.

A supplemental analysis to the formal accident investigation report, written by AvioConsult, using experimental flight-test expertise, is available for download:
Download this analysis   |   TOP


Beech C90, Australia 27 Nov. 2001

Just prior to, or at about the time the aircraft became airborne, the left engine failed. After liftoff, the aircraft remained airborne for about 20 seconds. The aircraft was rolling through about 90 degrees left bank, it struck power lines about 10 m above ground level and about 560 m beyond the end of the runway. It then continued to roll left and impacted the ground inverted in a steep nose-low attitude.

Cause of the accident
The accident was caused because of an incomplete and deficient engine emergency procedure. In addition, the real value and meaning of VMCA was neither clear to the pilot, nor to the accident investigators.

AvioConsult wrote a letter to the CEO of Raytheon Aircraft Company on 8 August 2006 expressing concerns about the definitions and the engine emergency procedures in the operator manual of the Beech King Air C90 and to present recommendations to improve. Ratheon never responded.

A supplemental analysis to the formal accident investigation report, written by AvioConsult, using experimental flight-test expertise, is available for download:
Download this analysis     |    TOP


Boeing 737-200, Algeria 6 March 2003

Just after passing V1, an engine failed. Almost immediately after liftoff, control of the airplane was lost and the airplane crashed, killing all but one on-board.
AvioConsult reviewed the accident investigation report and concluded that the engine emergency procedures in the Flight Crew Training Manual were inappropriate because the recommended control inputs were not leading to the 10% airspeed safety margin over VMCA that aviation regulations require when an engine fails during takeoff.
When using the recommended control inputs (for keeping the wings level), the actual minimum control speed that the airplane experiences right after liftoff, will be much higher than the minimum control speed that was determined during flight-testing and that is used to calculate both VR and V2.Actual VMCA was most probably even a little higher than V2 at the moment of liftoff; because the airplane continued a slow roll into the dead engine.

Cause of the accident
The accident was caused by inappropriate engine emergency procedures. The pilots are not to be held responsible.

AvioConsult recommended Boeing in July 2005 to improve the procedures, but Boeing responded that 'there was no compelling reason to change the procedures'.

An analysis of the Engine Failure Takeoff Procedures in the Boeing 737-200/300/400 Flight Crew Training Manual is available for download:
Download this analysis     |    TOP


Piper PA-31, New Zealand, 17 Dec 2002

Shortly after takeoff, the left engine quit operating for unknown reasons. The pilot feathered the propeller and returned to the airport for landing.
During the final turn, control was lost and the airplane crashed.

The analysis of this accident is included in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.   |    TOP


Piper PA-31P, Australia, 15 June 2010

While passing 7000 ft, the right engine failed and was shutdown. The airplane returned to the departure airport, but crash landed a few miles short of the airport on a road.
Download the original report with comments added


Piper PA-44-180, Netherlands 14 August 2002

A Piper PA-44-180 Seminole, owned and operated by Martinair Flight School in The Netherlands, crashed in a lake, killing an instructor and two students during a demonstration of flight with an inoperative engine.  The Dutch Transport Safety Board thoroughly investigated the accident and concluded that following the intentional shut down of the left engine, the fuel valve of the right engine was inadvertently closed rather than the valve of the left engine, after which the right engine quit as well and an emergency landing became unavoidable, according to the report. The report also concludes that the airspeed decreased below the stall speed, after which control of the airplane was lost at an altitude from which recovery was not possible.

But to the opinion of AvioConsult, this was not the cause of the accident. Neither the pilots nor the investigators did know about the limitations of a minimum control speed. A VMCA, although never determined, also exists due to asymmetrical drag (yawing moment) caused by one feathered propeller and the other not feathered.

The analysis (in Dutch language) with comments on the formal accident investigation report is available for download:
Download this analysis      |     TOP

Documentation review PA-44-180. The formal accident investigation report did not report on the training documentation used by the flight school. AvioConsult therefore asked, and received permission, to review the airplane and training documents. Many errors and deficiencies were found.

A limited analysis of the PA-44 documents, as used by the flight school (and also by other PA-44 owners) in the English language, is available for download:
Download this analysis       |    TOP

This analysis will also be useful to operators of other multi-engine airplane types.

AvioConsult wrote a letter to the CEO of The New Piper Aircraft, Inc. on 9 August 2006 expressing concerns about the imperfections in the Pilot's Information Manuals of Piper Aircraft and to present recommendations for improvement.
The company never responded.


Mitsubishi MU-2B, USA 10 Dec. 2004

Shortly after takeoff, the left engine failed. The pilot returned for landing via a left-hand circuit; the left propeller was feathered. The airplane did overshoot the final approach of runway 35R and was cleared to the next runway 28. The landing lights were then seen turning down toward the terrain. The airplane crashed; the two souls onboard were fatally injured.

The analysis of this accident is included in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.


Boeing 747, Netherlands 4 October 1992

Shortly after takeoff, both engines dropped off the right wing due to a fuse pin failure of pylon #3. The pilots decided to return to the airport and initiated a right hand turn (in the direction of the 'dead' engines). During the second right hand turn to position for the approach, the airspeed was decreased, obviously to a value below the actual minimum control speed VMCA2, upon which control of the airplane was lost and the airplane crashed in a residential area.
The formal accident investigation report does not even discuss the air minimum control speed, may be because in civil aviation regulations (part 25), a minimum control speed for two engines inoperative (VMCA2) does not exist (anymore). But in-flight, it definitely still exists and causes catastrophes if not observed.

Why did the pilots (and accident investigators) not know that not maintaining straight flight with a small bank angle away from the inoperative engines is almost certainly deadly when the power setting on the remaining engines is high and the airspeed is (getting) low? Most probably because the engine emergency procedures and VMCA definitions in airplane flight and operating manuals are incorrect or inappropriate / deficient, or because the engine-out training is inappropriate and incomplete. Refer to the Paper Airplane Control and Accident Investigation after Engine Failure that AvioConsult presents on the Downloads page of this website to learn about improving procedures and definitions.

The huge effect of bank angle on VMCA and VMCA2 was not considered by the accident investigators. This effect is calculated and illustrated in Paper The Effect of Bank Angle and Weight on VMCA that is also available for download:
Download this paper     |    TOP

Please also refer to the comments on the Boeing 737 FCTM above.


Saab SF-340B

Ten minutes after takeoff from runway 24, an oil pressure warning of the right engine (#2) made the captain decide to return to the airport. He left the affected engine #2 idling; its propeller was not-feathered. The wind was 270/ 11 kt when the captain accepted landing runway 06. On short final, with an actual wind of 280/ 8 kt, the airplane was displaced to the right. At 45 ft Radar Altitude, the captain therefore decided to go-around using the thrust of the left engine only; the right engine was kept idling. The airplane crashed 13 seconds later, far to the right of the runway.

Download this paper and learn about investigating engine failure related accidents.   |  TOP

The analysis of this accident is also included in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.     TOP


DHC-6-100 Twin Otter

A De Havilland DHC-6-100 airplane carrying skydivers crashed into trees and terrain after takeoff. Witnesses at the airport reported that, shortly after the airplane lifted off from the runway, flames emitted from the airplane’s right engine.

The analysis of this accident is included in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.    |   TOP


EMB-120ER

During the takeoff of an EMB-120ER twin-turboprop airplane for a revalidating command instrument rating, the training and checking captain retarded the left power lever to zero torque just after liftoff.  The airplane crashed, both pilots died in the accident.

The Safety Report was reviewed and many suggestions for improvement were included. This review is to learn more about airplane control after engine failure.

Download the safety report with review and learn more about investigating engine failure related accidents.

The analysis of this accident is included in the YouTube video (downloads page) and in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.       |      TOP


Jetstream 4100

During takeoff, at about the instant of rotation, 5 sec. before liftoff, the right (#2) engine failed; the takeoff was continued. Control was lost shortly after liftoff, the airplane crashed.

The thorough analysis of this accident on control after engine failure is included in the paper Airplane Control and Accident Investigation after Engine Failure, please refer to the Downloads page.     |     TOP


Cessna 310Q

During final approach, a go-around was initiated. The left engine failed, after which control was lost. The airplane crashed, killing both persons on board.

The accident report was reviewed, and comments and recommendation for improvement of Airplane and Training Manuals are presented.      |     TOP

Download the safety report with comments      |     TOP


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