November 23, 2020


Sofema Aviation Services (SAS) comments on Aircraft Accident Investigations and considers the use of Reconstruction Techniques.


The reconstruction of the last stage of the flight, i.e. the accident phase, necessitates close coordination between many groups as part of the investigation, but it is the primary concern of the Operations Investigation.

The Operations Investigation – The intention should be to build up a complete picture of the final events as they occurred in proper sequence and evaluate their interrelationship.
The period of time to be covered will depend upon the circumstances. In general terms it should commence at a stage where the flight departs from normal safe operation and it can terminate when the inevitability of the accident is indisputably apparent.
This need not necessarily be the time of crash impact. For example in the case of a structural failure in cruising flight, once the wings have broken off the accident is inevitable, similarly in an unrecoverable “jet-upset” situation, once the aircraft is too low to regain a normal attitude without grossly exceeding many limitations the accident is bound to follow.
In take-off and landing accidents, however, the crash impact will be the terminating event and it may be necessary to use this as the starting point of the reconstruction and work backwards for the purpose of synchronising the various sources of information which may have been established on a sequential basis by other investigation groups.

The Flight Recorder Investigation will provide the basis of the reconstruction and the radiotelephony recording will provide the necessary link with related activities on the ground.

The Structures Investigation should be able to determine the aircraft configuration and the Human Factors Investigation may add to that evidence. It may also establish certain important considerations regarding the condition or operating efficiency of the flight crew.

The Powerplants Investigation should be able to indicate the degree of engine power being developed at the time of impact.

The Systems Investigation should be able to contribute to the aircraft configuration determination in some detail.

Finally, the reconstruction should be considered in the environment indicated from an evaluation of all the witnesses’ statements and in the meteorological conditions determined by The Weather Investigation.

Note – The reconstruction of ATS surveillance system data may bring to light items of importance in the Operations Investigation in relation to the other areas of the occurrence investigation. It may also happen that the particular characteristics of the occurrence necessitate not only the reconstruction of the occurrence flight but other previous flights.

Next Steps

Please see details of the following course available as classroom or webinar with Sofema Aviation Services:
Aircraft Accident Investigation Process & Procedures – 3 Days

Additionally, please visit or email


Accident Phase, Aircraft Accident Investigation, aviation, Operations Investigation, Reconstruction Techniques