Originally Posted by
tdracer
At best, this would be something of a 'proof of concept' - the FDR and CVR would still be required as I don't see the feds changing the regulations anytime soon. Any attempt at obtained an "ELOS" (Equivalent Level of Safety) for at satellite based system to allow removal of the FDR and CVR would get laughed out of the office.
Before the regulators would even consider changing the regulations, or even an ELOS, you'd need tens, no hundreds of millions of operational hours,
plus a significant number of actual crash events where it's demonstrated that the satellite based system provided better (or at least as good as) information than the conventional FDR/CVR systems, and
NO events where the satellite system didn't provide equivalent data.
Maybe in a couple decades...
DFDR and CVR are
not flight safety critical despite what marketers at INMARSAT and media reporters might say. However, they are the subject of mandatory regulation. It is unlikely that the regulation can be met by offboard recording devices with a tenuous communications link to the aircraft. In consequence, the 'cloud' recording will be a fashionable adjunct to the existing systems. As I said before, with geostationary systems requiring the aircraft antenna to maintain its link to the satellite by motoring to point toward it is extremely unlikely that contact would be maintained in all but the gentlest of emergencies. A LOC incident would almost certainly lead to immediate disconnection. This means that the requirement to record all stages of an emergency
cannot be met by INMARSAT. This is not opinion it is unquestionable. Therefore, we are left with the INMARSAT marketing department achieving another coup.
It might be possible with the correct antenna array to maintain contact with a LEO satellite system using omnidirectional antennae and cellular style technology. But even there that would have to be proved. As a test an aerobatic aircraft should be fitted with the proposed systems then depart normal straight and level flight and carry out a series of extreme maneuvers from height down to sea level. Assess whether the satellite link worked. This should be extremely simple to do. It should be done before any expenditure by any party.