> However, engineers also could not rule out that some or even most of this frequency offset was due to the crystal oscillator inside the transmitter warming ba

> However, engineers also could not rule out that some or even most of this frequency offset was due to the crystal oscillator inside the transmitter warming back up after the power interruption. Didn't the plane have two power interruptions, the first of which it is known that the plane wasn't in the process of crashing at high velocity? I wonder what effort was made to compare them, possibly allowing the effects of crystal drift and Doppler to be separated? Maybe any unexpected frequency offsets after the first power cut can be entirely attributed to the crystal warming up after the power cut? Maybe it could be assumed that the crystal behaves similarly after each power cut, as crystals are typically repeatable with temperature? In that case the characteristics of the crystal are known after the second power cut and Doppler can be determined. I'm sure this would have been thought of, but one has to ask.