With some Flight Data Recorders gone unrecoverable during crashes , what's the argument for not changing their locations, like wings or engines?

Given their utility after accidents, why not increase the redundancy even more by placing separate boxes in each engine for example.

I understand that military aircraft have jettisoned Recorders that signal their location for recovery. Could this option be considered with Jettisoned Engines even before the crash in case of Extreme Load or excessive vibrations ?

  • 2
    $\begingroup$ There are some Deployable Black Boxes, but they are quite expensive and rarely needed. $\endgroup$
    – Lnafziger
    Commented Apr 24, 2018 at 14:29

3 Answers 3


The simplest argument to me is that no location on the aircraft is particularly special when it comes to locating black boxes in this sense. The recorders that aren't found are either in exceptionally remote locations or underwater - I don't see anything special about an engine that makes it more likely to be found than the wreckage of the fuselage.

No matter where you place them, there are going to be circumstances where they can't be found.


That is soon to be. Starting in 2019 Airbus is equipping the A350 with redundant, floating, jettisoned recorders. They will be in addition to the usual ones inside the aircraft.

None of the articles I've read indicate whether it's a standard feature or an option.


FDRs are already in the most survivable location, in the tail. Look at any crash site and the tail cone is usually the only intact major component.

You don't want to jettison them because you need to record data right to the point of impact. The jettisonable devices that are used today are crash locator beacons, not data recorders. They've been around since the 70s.

Ultimately what will make all this moot is that going forward all of the data that would be recorded by the FDR/CVR will be transmitted and recorded in real time via satellite... some day.

In theory, it could be possible to jettison an engine on a wing mounted engine aircraft, because they have fallen off on their own and the airplane was still flyable because there was little CG shift. Hmmmm what about whoever is below this falling object the size of a single car garage, which may get discharged over populated areas with some regularity?

  • 3
    $\begingroup$ Regarding transmission of flight data to or via satellite, see Could the CVR and FDR record to the cloud? $\endgroup$
    – user
    Commented Apr 24, 2018 at 13:59
  • 1
    $\begingroup$ Pretty much anything is possible but in commercial aviation things proceed at a snail's pace because of the cert process to bring any new system or concept to the market. Large flat panel displays were common in corporate and general aviation many years before they finally started to appear in airliners. $\endgroup$
    – John K
    Commented Apr 24, 2018 at 14:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .