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Malaysia Airlines Flight 370: Australian Officials ‘Very Close’ to Finding Wreckage
Australian authorities leading the search for the missing Malaysia Airlines plane reported they may be “very close” to locating the site of the wreckage after the Royal Australian Navy picked up signals that could be coming from the ill-fated aircraft’s flight recorders. During a search Sunday by the naval ship Ocean Shield, two separate and distinct “pinger” signals were detected in an area 1,040 miles (1,680 kilometers) northwest of Perth, which the most recent analysis of satellite data has… (www.frequentbusinesstraveler.com) 기타...Sort type: [Top] [Newest]
No ELT frequencies transmit through water. Once the plane begins to sink the ELT signal is lost. If you have an emergency over water, manually engage the ELT immediately to begin transmitting. Once you ditch your signal ends.
Best you research aircraft FDR and CVR units and their properties, and the Honeywell type on 9M-MRO and you will find they do transmit through water up to and over about 6000 meters deep of water, are designed to retain integrity in salt water for up to two years, up to 2000 dg C for over an hour and up to 5000g impact force. In deep water where they have possibly, that's possibly, identified BB pings there can be distortion from the water layers and temperature and - yes the reason they are so expensive is battery does last for 30 plus days.
It only has to transmit a single frequency and think of your tiny personal devices that last for ages and are used constantly before needing a charge, then think about the size of ultra high quality battery able to fit in a FDR unit.
It only has to transmit a single frequency and think of your tiny personal devices that last for ages and are used constantly before needing a charge, then think about the size of ultra high quality battery able to fit in a FDR unit.
Satellites can't pick up audio signals in the water yet, so I figured we were discussing the radio frequency transmissions in the 121.5Mhz and 406Mhz VHF bands which would not travel though much water.
VLF is way lower frequency that VHF and can still only penetrate ~20 meters of water.
VLF is way lower frequency that VHF and can still only penetrate ~20 meters of water.
Well, they can pick up SOME audio signals, but not of this frequency. An example of an audio frequency they picked up is the Fukushima earthquake.
OK thanx. Soory for my ignorance.
Even if it would transmit through water, it would not last more than a day or 2... To power a VHF Transmitter for this time period, would require a HUGE battery.