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New Information May Narrow Down Malaysian Jet's Path
mdsolar (1045926) writes with this excerpt from Slate on the still-missing Malaysian Airline flight "In a case that is swirling with uncertainties, a few pieces of evidence have stood apart for seeming reliability. Among them was the revelation last Saturday by Malaysia Prime Minister Najib Razak that his country's investigators, in collaboration with U.S. authorities, had analyzed an electronic ping that MH370 had broadcast to the Inmarsat satellite at 8:11 a.m. on the morning of the disappearance. Based on this data, the investigators had determined that at that moment MH370 must have been somewhere along one of two broad arcs: one which passed through Central Asia, and the other of which covered a swath of largely empty Indian Ocean, far to the south. The revelation left a burning question unresolved: what about the six earlier pings, which had been exchanged between the aircraft and the satellite about once per hour? Could any position data be deduced from them? Today, Inmarsat revealed some crucial information. 'The ping timings got longer,' Inmarsat spokesman Chris McLaughlin stated via email. That is to say, at each stage of its journey, the aircraft got progressively farther away from the geostationary satellite's position, located over a spot on the equator south of Pakistan, and never changed its heading in a direction that took it closer—at least for very long."
The planes have ELTs designed to activate upon impact and relay their GPS location to satellites (Steve Fossett's plane would've been found within hours if he had had one of these). AFAIK those aren't waterproof though. The escape slides (which double as rafts) should have EPIRBs aboard, which are waterproof. However if the rafts aren't deployed then obviously they'll sink and the EPIRBs won't do a whole lot of good.
/. which cost $100k per plane, an EPIRB only costs a few hundred dollars.
The black boxes give off a 35 KHz acoustic ping every second. The batteries should be good for 30-35 days. Unfortunately, 35 KHz sound attenuates rapidly in seawater, so you only likely to hear it up to about 2 km away. If the plane is sitting in more than 2 km of water, the only way you'll hear the pings is if you're very lucky on the surface, or from deep water submersibles.
I think the assumption was that you would have enough radar data to narrow down the search area to a few hundred or few thousand square km at most. AF447 was probably considered a fluke. Now that a second plane has "disappeared" in a similar manner, expect to see the required locating equipment changed. One obvious change would be to equip all commercial aircraft with an EPIRB designed to float free if the plane sinks. It won't give you the plane's exact location due to wind and currents, but it'll prevent these "we have no idea where the plane is" situations. Unlike the previous locating idea posted on
Radio transmissions do not occur at the speed of light.
Radio waves and light waves are both electromagnetic radiation, just at different wavelengths. In vacuum, electromagnetic radiation travels at speed c for all wavelengths. In non-vacuum media, there may be some dispersive effects that cause the speed to change with wavelength, but those effects are very small in air.
In short, radio waves travel at the speed of light because, in a very real sense, radio waves are light, just not light at a wavelength our eyes can see.
If it weren't for deadlines, nothing would be late.
http://www.wired.com/autopia/2014/03/mh370-electrical-fire/
I believe something like that happened. Occam's razor and so on...
The fact that the pilot had built his own simulator also has a mundane reason that somebody on pprune had tracked down: He assisted with giving a real pilot's feedback to a third-party developer of aircraft for flight simulators (X-Plane IIRC).
Here's a map of the pings:
http://theaviationist.com/wp-c...