WSJ comments
A newish Wall Street Journal online story which leads with the assertion that an AAIB interim report is expected soon goes into some ELT detail--including a strong suggestion that someone thinks a possible ELT role in the cause likely enough to consider a possible recommendation for temporary removal of them from 787s.
Regarding the legalities of ELT-free operation, the WSJ article asserts that while they are required on planes to be used for passenger flights in the US, it is allowed to continue operation with them inoperative for as long a 90(!) days before replacement or repair, and further asserts that no case of ELT actually being useful in a large airliner incident has been recorded in the last couple of decades. It asserts that European rules are similar to the US rules.
Lastly, and not in the WSJ article, I learned that this ELT battery is far larger than I might have thought. I've lost the reference, but believe that for this Honeywell model the battery weight was given as a bit over six pounds. If true, that is plenty of energy to serve as a major ignition source if something goes seriously wrong.
[edit: another poster has cast very serious doubt on this battery weight claim. I know I saw it written, but it surprised me. Most likely it was false--possibly by misconstruing the entire ELT weight as being the battery weight]
Last edited by archae86; 18th Jul 2013 at 01:29.
Reason: cast doubt on battery weight