Protection and Location of Flight Recorders (black box)

Flight recorders for the retrieval of data for accident investigation purpose must be adequately protected and so located in an aircraft that the recording media will survive in the event of a crash situation .The adverse factors against which protection is necessary are mechanical damage due to impact and acceleration forces,fire damage,and chemical attack by hydraulic,de-icing and fire extinguishing fluids,fuels and acids.Protection must also be afforded against the effect of sea water,and to cater for cases where an accident occurs resulting in wreckage entering deep water,the recording medium container must also be provided with separation and flotation facilities. 

                      The protection facilities are,of course,'built in' to the design of a recorder and so may be considered as the primary means of ensuring survival of the recording media.The location of a recorder in an aircraft is, however, also an important factor to be considered in this respect, and from the evidence of aircraft accidents it is shown that the rear fuselage and tail unit structure is the section most likely to survive, or be the least severely damaged.For this reason therefor,a protected flight data recorder is installed in the rear of an aircraft.

                     In addition to the foregoing protection and location requirements,it is also necessary to provide recorders with means to facilitate their identification in conditions following a crash.This is usually done by adopting a distinctive color scheme;thus, contrary to the 'black box' cliche frequently adopted in news media reports of a crash, the box could well be fluorescent orange.