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Does anyone know how accurate the FlightAware data is and where it actually comes from? The last two data points for the accident aircraft have very slow speeds of 109 and 85 knots. Although the altitude still reads as one or two hundred feet I'm wondering if the aircraft was actually on the ground at that point and was sliding to a stop, or if they were airborne and stalling, or if the data just isn't good enough to be drawing any conclusions from it at all.
How accurate? The answer is, in all likelihood, not very.
The data on FlightAware will have come from one (or both) of two possible sources.
One is FAA radar data, via ASDI, though that's fairly coarse data and I don't see how speeds that precise could have been resolved from a radar feed.
The second is ADS-B data which, depending on the aircraft fit, is likely to be both considerably more accurate and have better time resolution.
BUT, with ADS-B the caveats are:
Speed will almost certainly be groundspeed rather than TAS/IAS and so without knowing the wind on the nose should be used with caution.
Altitude is relative to QNE (in other words it's effectively a flight level, even below the transition altitude) so you would need to know the local QNH at the time of the accident to derive height AMSL or AGL.
Speed is always GS in kts
At time of accident (1900Z):
Wind 210/07
QNH 1009.
Speed showing almost correct, altimeter a little on the high side.
The appraoch track and last three positions are here:
https://www.dropbox.com/sh/e47bckfnefp9hgs/eU7Tw_WfBM
It appears after what's a normal south traffic pattern 105 kts right before the runway threshold is very slow, also 123 kts on the previous position is slow. The last position is the wreckage.
Reminds me of the Amsterdam TK 737 crash, when autothrottle disengagement went undetected.