Let's consider the following scenario:
A flight is in trouble, the flight data recorder senses it(Anything the computer would sense and deem would result in an accident), it drains fuel from the tanks into its tank working with GPS to drain just enough fuel to take it to the manufacturers base, taking into consideration flight conditions, head wind or tail wind. It detaches from plane before impact, opens up its 6 arms with drone rotor propellers, fires its batteries starts flying at speed, once it reaches rotation speeds, it spreads its fixed wings and fires its jet engines because fixed wing aircraft are more efficient than rotor wings, it then drops its heavy rotor wing powering batteries to save fuel and flies to its manufacturer's base. It might even use jet engines to power it rotor wing phase

Version 2 would not detach but can cut itself out of the aircraft. If it senses water it will use its a compressed air tank that it will leave in the aircraft to inflate a rubber tube that will raise it to the surface floating so it can take off as a water plane/drone or rotor wing drone

Is a smart flight data recorder possible as described in this scenario? What are the drawbacks or impediments?

  • 1
    $\begingroup$ the point is that we analyse data to find out what happened, because most often than not, that specific combination of factors never happened before, so, how would a computer "deem [that it] would result in an accident"? $\endgroup$
    – Federico
    Apr 9, 2019 at 11:05
  • $\begingroup$ if an aircraft is not doing what it should, ALL faulty systems become known to the computer because its connected to them if certain systems cannot be repaired and with known aircraft physics a computer can tell if it will result in a crash, the same way a simulator works... we do sometimes punch in unkown parameters into a simulator, situations that would result in a crash $\endgroup$ Apr 9, 2019 at 11:13
  • 2
    $\begingroup$ an aircraft could be doing something that it should not do, and yet have no faulty system at all. $\endgroup$
    – Federico
    Apr 9, 2019 at 11:16
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    $\begingroup$ @securitydude5 You seem to believe that a computer being connected to something makes that computer omniscient. That simply isn't the case. $\endgroup$ Apr 9, 2019 at 14:01
  • 1
    $\begingroup$ Just because something is a bad idea doesn't mean it is bad to ask the question... $\endgroup$ Apr 9, 2019 at 17:14

3 Answers 3


Your proposal is that the FDR should stop recording before the incident is over. Total non-starter.


Why would you use such a complex and failure prone system? Assuming you mean that you would fly the flight data recorder (FDR) to the base of the manufacturer. There a couple of drawbacks:

  1. Flying the FDR before impact means that you miss vital information about the situation just before impact
  2. The added weight of the construction means that you are flying around for years with lots of dead weight. Which is very expensive. Airlines are really interested in you if you can shave half a kilo of every seat. It would save them millions over the lifespan of the aircraft
  3. FDR's are not decoded by the manufacturer but by specialized agencies such as the BEA and NTSB
  4. Most crashed happen around take off and landing, so your smart system has to act fast
  5. All FDR and cockpit voice recorders are made really strong so that they can survive the impact of the crash, in addition they are located at the back of the aircraft. They picked this location as the tail section remains the most intact in a crash. Latest generation FDR's uses solid states disks for storage, greatly increasing the resistance against impacts.

In addition to the other reasons Version 1 is a bad idea:

  • A drone that could potentially fly halfway around the world is very heavy, unless you put it right in the center of weight launching it would imbalance the airplane. You can't put it in the center of the airplane because you want people and stuff there, so it would have to go at one extreme or the other. The farther from the center of weight the greater the moment arm, detaching that weight will change the flight dynamics making a bad situation worse
  • It only makes sense if you have an ejection system for this drone, with explosive bolts and a rocket to get it clear. You can't just stick this anywhere, airplanes would have to be re-designed to accommodate it. That's expensive, and would eat into passenger and cargo space
  • Taking fuel from the tanks will take minutes, few emergencies give you that amount of time. Plus you're taking fuel that the airplane may need if it recovers. If it wasn't going to crash before it probably is now
  • There's a better alternative in the form of satellite communications which would stream CVR and FDR data without all the Rube Goldberg crashy-crashy stuff

Now let's talk about Version 2:

  • Having a data recorder cut itself out of a submerged airplane is probably detrimental to the survival possibilities of the occupants inside
  • If an airplane has ditched then it's unnecessary, if it has crashed into the ocean the chances of the cut-out mechanism being intact enough to work are extremely low. Even it it works it's very possibly trapped by debris
  • There's a better alternative in the form of satellite communications which would stream CVR and FDR data up to the moment of impact
  • $\begingroup$ Unfortunately, if the airplane is submerged and there are people in it, they're mostly going to die. I doubt the cut-out mechanism would really affect that: there's no reason it needs to open a hole into the passenger cabin and opening the doors to let people out will create much bigger holes. $\endgroup$ Apr 9, 2019 at 17:08
  • $\begingroup$ Your version 2 comments are unfortunately all incorrect. Military aircraft have been using deployable recorders for years, precisely to aid in recovery of the aircraft during water crashes. $\endgroup$
    – user71659
    Apr 10, 2019 at 0:11
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    $\begingroup$ There's a huge difference in what the OP is proposing and deployable recorders, which are basically pods @user71659. I think deployable recorders make perfect sense, especially for ETOPS airplanes, it's the whole cutting itself out and then flying as a drone part that I have problems with. $\endgroup$
    – GdD
    Apr 10, 2019 at 7:52

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