Loss of engine cowl door

Citation

(2002), "Loss of engine cowl door", Aircraft Engineering and Aerospace Technology, Vol. 74 No. 1. https://doi.org/10.1108/aeat.2002.12774aab.021

Loss of engine cowl door

Keywords: Safety, Aircraft

An ATR42-300 aircraft was on a standard passenger flight from Teeside to Paris. After take-off the cruising altitude of 19,000 ft was reached around 20 minutes later, with all flight deck indications remaining normal. At this point the flight deck crew were Informed by the cabin crew member that a passenger had reported a panelmissing lorn the No 1 engine.. The cabin flew member also noted that she had heard a noise during take-off; which she had attributed to movement of baggage in the aft compartment.

The flightdeck crew could see from the flight deck that part of the No l engine outboard cowl door was broken off and decided to return to Teesuide. They informed ATC of a slight technical problem and were radar vectored back to the airport, limiting the airspeed to 180 kt to miniraise the possibility of additional damage. The crew declined to declare an emergency but ATC placed the airport emergency services at local standby. During final approach the crew spotted a panel on the runway thatthey had used for take-of; near its threshold. The aircraft overflew the panel and landed without further incident. A cowl door and a number of pieces of smaller debris were found on the runway near to the point at which the aircraft had started its takeoff run.

On the ATR42 the engine bays are covered with an inboard and outboatrd cowl door, each approxlmately 3.2 ft wide and 3.5 ft high. measured circumferentially, and weighing appoximately 15 klb. A weekly Check was carried out on the day before this incident and this Included the requirement for the inboard and outboard cowl doors of both engine nacelles to be opened, The door closing and fastening of latches Is believed to have been carried out normally. The next morning the captain of the aircraft flight flew carried out a pre-flight walk- round inspection lie believed that all engine bay doors had been flush with the surrounding panels although because of their height above ground. he was not able to confirm that the latches were engaged.

Aircraft examination

This showed that he panel recovered from the runway comprised the lower three-quarters of the left cowl door of the No 1 engine bay. A generally longitudinal fracture had separated this portion from he remainder of the door which remained attached to the door hinge. the fracture was consistent with the effects of gross overload. The fasteners attaching the longitudinal beam on which the door hinges were mounted had failed due to overload, and the beam had pivoted around the right doff hinges. The right door remained attached by its latches and retained the beam. The left door was reportedly found with the fog-ward and lower latch operating handles open and the aft latch with ils operating handlefound. and spring-loaded catch closed. Localised Impact damage to the engine mount flame was

Examination showed that the detached prortion of the door had struck the airframe in a number of places resulting in damage which included the following:-

A 5 inch split in the left wing leading edge, shattering of the left No 7 cabin window, scrape damage to the fuselage left side below the left No 10 cabin window, impact damage to the left sponson hydraulic reservoir access door (conmposite material), and battering damage to the left sponson composite fairing by the detached hydraulic reservoir access door.

No evidence was found that previous similar cases of engine bay door loss from the ATR-42 had occurred, although the accident closely followed the loss of fan cowl doors from Airbus aircraft over

Recommendations

It is recommended that the operator reviews its procedures and working practices aimed at suring that all aircraft doffs are correctly latched before flight.

Following investigation and analysis of the incidents involving other types of aircraft previously referred to, the AAIB made the following Recommendation (No 2000-30) in 2000, AAIB Bulletin 7/2000. It is recommended that the JAA and FAA consider a requirement for future aircraft certification for a system to provide flight deck warninmg of all unlatched access panels or doors that could hazard the aircraft if left unfastened.

ReferenceAAIB Bulletin 6/2001