Expert: Laura Laster - 7/2/2010

Question
hello man
I am aerospace engg student.I need some information related to aviation accidents and blackbox
question
1.What are the standard procedure followed by the investigative committee after a crash,where does the black box come into play?
2.what are the parameter measured by the black box?
3.Is the blackbox used only in commercial airline or is it used in combat aircraft also?
4.normal location of the blackbox?
5.Any major crash solved just due to the recovery of blackbox?

Answer
Hello,
I will do my best to help you with your questions:
1) The standard procedure is for the country where the accident occurred to have their transportation safety investigative group immediately begin searching for the "black box" once the rescue operation is completed - survivors removed, and so on. The "black box" is actually a large orange metal box with many layers of protection surrounding the central data recording circuits. Most of these boxes, which are really called Flight Data Recorders, are digitally recording hundreds of parameters on a series of chips in the Flight Data Recorder, so they are really known as Digital Flight Data Recorders (DFDR).
2) In the US, legally they are required to record heading, altitude, engine power setting, time, transmissions made on the radio, airspeed, and vertical acceleration. However, many more parameters are recorded so that investigators can completely piece together the final moments of a flight.
3) I believe military aircraft use flight data recorders as well, but unfortunately I am not sure of this.
4) Normally, the flight data recorder is located in the tail of the aircraft as this area is generally considered to be the most structurally strong portion of the aircraft. It would be normally just past the pressure bulkhead of the aircraft.
5) Many major crashes were solved with heavy use of data recorded in the flight data recorder, but it's impossible to pinpoint a case where that was the only item that told investigators what went wrong. Normally, investigators also evaluate the terrain impact marks, all the other wreckage (engines, instruments, control surfaces) and information from witnesses to put the whole puzzle together. I really don't think there was ever an accident where that was the only thing that solved what happened.
http://en.wikipedia.org/wiki/Flight_data_recorder this is a good link which also may interest you for some pictures of the flight data recorder.
Laura