Monday 16th March 26 Aircraft Accident Investigation – a retired investigator reflects. – Peter Coombs


We are fortunate that Peter’s brother is a member of the club and cajoled Peter into speaking to us.

Peter entered the aircraft industry in 1965 as a Student Apprentice with the FiltonWe are fortunate that Peter’s brother is a member of the club and cajoled Peter into speaking to us.

Peter entered the aircraft industry in 1965 as a Student Apprentice with the Filton (Bristol) division with the British Aircraft Corporation. His industrial experience covered most laboratories and departments involved in design, manufacture testing and maintenance of large transport aircraft and missiles. This culminated in being appointed as a design engineer on the Concorde SST Project. Following a period spent at the College Of Aeronautics at Cranfield, he graduated with a Master of Science degree in Aircraft Design in 1971. Peter has been an Inspector of accidents since 1972 and has participated in the investigation of civil aircraft accidents and supported boards of enquiry into military accidents world-wide for forty years. Over this period, he has carried out field investigations on more than 200 accidents and lesser investigations on a further series of more than 150 accidents not involving full deployments.

He started his talk with a review of the history of the AAIB (Air Accident Investigation Branch). The first recorded investigation was into an accident in which Orville Wright was the pilot! Sadly, the passenger died which prompted the investigation and thus the beginnings of the service we know today. In 1915 it was an acknowledged part of the Royal Flying Corps and through various changes until in 1972 it became part of the Civil Aviation Authority and since 1983 it has been part of the Dept of Transport.  

A permanent staff of 54, 28 of whom are inspectors all with their own specialities, are based at Aldershot. They can be called to all parts of the globe at a moment’s notice and can call upon all manner of specialist agencies. In investigating accidents, they have complete independence and do not attempt to apportion blame to pilot, manufacturer or other bodies. Their function is to establish the cause for the purpose of prevention. To back up their work they can resort to strong legal powers.

Peter showed pictures of a number of accidents and described in some detail the work that went into discovering the cause.

 One of particular interest was an RAF Chinook helicopter, where following  re- manufacture the aircraft was being tested. An essential part in the rear gearbox had been fitted incorrectly and though it worked under test in both blades on and off at full power, it wasn’t until a load was applied that the critical part lost engagement and thus the blades their synchronicity with the front blades with disastrous results and craft crashed to the ground without too much damage.

Of all the accidents with which Peter had been involved, he found the most intriguing to be that of an Avro 748 which crashed into fields in Leicestershire. The fuselage minus both wings lay in a field and the wings were located some half a mile back laying side by side. A local farmer came forward with a rear door from the aircraft which he had found in a field some way back from the wings!

It transpired that a fault in the door had occasioned it parting form the fuselage and hitting and lodging in the tailplane whereupon the plane became unflyable due to dramatic changes of pitch until eventually the wings were torn from the fuselage. Sadly, all three crew members died.

A fascination insight into a world in which we hope never to be personally involved and there followed many questions.

A more detailed report of  his talk to the Loughborough Branch of the Royal Aeronautical Society can be found here:

https://loughborough-raes.org.uk/ewExternalFiles/220315%20AAIB.pdf