Flight 370 changed course and altitude, and then maintained the new bearing for hundreds of miles and an additional hour of flight after losing contact with ATC (air traffic control).
The Malaysian military reported Flight 370's altitude as 29,500 feet. This conflicts with eyewitness accounts from fishermen reporting a large aircraft at a much lower altitude around 1,000 meters (3,000 feet). If the radar altitude is correct, this suggests the aircraft was not experiencing decompression, as the pilots would descend as an emergency response to decompression. If the fishermen's report is accurate, then decompression would not be an issue.
Releasing data from the U.S. intelligence space-based network would reveal U.S. capabilities. The Strait of Malacca is a key shipping lanes chokepoint, and is thus of strategic interest to the U.S. and other nations with space-based assets. U.S. authorities have already revealed that U.S. coverage of the area is "thorough."
This confirms that U.S. communications monitoring and space-based assets cover the seas around the Strait of Malacca. Given what is known about these monitoring and space-based assets, it is likely that the U.S. intelligence agencies have additional data but are not revealing them, as this would provide direct evidence of U.S. capabilities.
We can surmise that the U.S. maintains thermal imaging capabilities that can detect more than large explosions. We can also surmise that the communications monitoring networks picked up any signals from the aircraft or related to the aircraft.
That the head of the C.I.A. publicly professed ignorance is interesting. What course of action would one pursue if one wanted to keep U.S. capabilities secret? Publicly proclaim ignorance.
This is not to suggest that the U.S. "knows where flight 370 is;" it is simply to note that this is not "open ocean" comparable to the mid-Atlantic where Air France Flight 447 went down five years ago. This is a strategic chokepoint of great interest to the U.S., and therefore it is likely that U.S. networks and space-based assets collected data that would either exclude certain possibilities or make other possibilities more likely.
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