Originally Posted by
NigelOnDraft
Current Range seems ~2.5NM, 30days.
So you asking for something that lasts 6times as long (maybe a bit less due being "smart"), and is 1000x as powerful? So needing say battery capacity 2000x current kit?
That is a "major" change, and bearing in mind the 'g' / depth / other strict requirements I suspect unrealistic. NB just stuffing big batteries into autonomous kit is hardly flavour of the month right now (787 LHR fire).
Bear in mind these things do not directly save any lives, and assuming they find the Air Asia DFDR / CVR soon, just save some search effort.
Not necessarily a 1000 times more powerful - choice of a different frequency could easily increase the range. Apparently the frequency was chosen as it was not a 'natural' frequency. Encoding would provide the same 'not natural' effect so the frequency could be one that has longer range in water.
The rate of transmission could be as low as once every 3 minutes instead of (I believe) around once every half second.
BEA also put forward a request for this type of improvement (from the BEA report on search operations for AFR 447
http://www.bea.aero/fr/enquetes/vol....11.2012.en.pdf ):
B.3.1 Enhanced battery life
The use of ULB beacons with 90 days(14) autonomy would have made it possible to
extend the search for the ULB beacons in this vast area. The BEA recommended that
EASA and ICAO extend the regulatory transmission time of ULBs (from 30 to 90 days)
B.3.2 Additional ULB
Using beacons capable of transmitting on lower frequencies (for example between
8.5 kHz and 9.5 kHz) would have facilitated the detection of the wreckage. Indeed,
military resources, typically deployed in the early days to take part in SAR operations,
are equipped with sonar suited to the detection of low frequency signals, and
in addition the use of lower frequencies increases the detection distance. The
BEA has recommended that EASA and ICAO make it mandatory for aeroplanes
performing public transport flights over maritime areas to be equipped with a lowfrequency
beacon.