Why Can Pilots Still Turn Off Their Transponders?

[bhsmte]

Others have answered why transponders can be turned off; they are correct. You speak of another system; that they have also. They are called Emergency Location Transmitters (ELTs) These have independent battery power and activate automatically in a crash. Bach when I flew they were just coming into use in General Aviation. The early ones worked so well that they sometimes activated as a result of a hard landing, or high G loading during aerobatics. The FBO at our local airport got at least one "do you know where your aircraft is" call a month from the MoT. I think that they have improved greatly since then.

Why they did not function in this case is thus far not known.

Here is a link to info from one company's ELTs for commercial aircraft: ELTs for Commercial Aircraft

Yes, I am aware of the ELT and understand it has limited range.

What I was thinking of, was an independent device, that would send data to a satellite throughout a flight, that could replace the info currently contained in the black box. I realize this costs money, but it is kind of disturbing, a 200 million dollar plane can go down, with over 200 people on board and we have to find a box on the plane to figure out what happened.

At the least, flights that plan to travel over large bodies of water should have this capability.

 

[OGM]

I would simply embed the location and altitude info in to the ACARS data stream. If something out of the ordinary happened or when manually triggered...the system could transmit location, altitute every 20 or 30 seconds if external power was feed to the unit. If the system was running on batteries. It could transmit every minute or so.

A plane with a ground speed of 600MPH is moving 10 miles per minute. Hence I would want frequent updates sent if an unusual condition was detected.

 

[bhsmte]

I would simply embed the location and altitude info in to the ACARS data stream. If something out the ordinary happened or when manually triggered...The system could transmit location every 20 or 30 seconds if external power was feed to the unit. If it was runiing on batteries. It could transmit every minute or so.

A plane with a ground speed of 600MPH is moving 10 miles per minute. Hence I would want frequent updates sent if an unusual condition was detected.

Makes sense.

 

[MarkRohfrietsch]

I would simply embed the location and altitude info in to the ACARS data stream. If something out the ordinary happened or when manually triggered...The system could transmit location every 20 or 30 seconds if external power was feed to the unit. If it was runiing on batteries. It could transmit every minute or so.

A plane with a ground speed of 600MPH is moving 10 miles per minute. Hence I would want frequent updates sent if an unusual condition was detected.

Interesting.

 

[OGM]

Actually it might not cost much to make those changes because that information is already on the data bus. It might be able to be done solely with software changes.