PPRuNe Forums - View Single Post - Turkish Airlines cargo 747 crashes in Kyrgyzstan
Old 17th Jan 2017, 14:47
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Magplug
 
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@Kulverstukas I also ran the figures and came to the same inexplicable conclusion.

I can say from my observations of the ADS data.....

- The approach was established Vref +5 prior to 1000' AAL so a stable approach.
- The descent rate was consistent with a 3deg glideslope, a false G/s capture would have been steeper but descending to the same correct touchdown point.
- The ROD was consistently accurate as one would expect with an ILS approach coupled to the autopilot.
- The QDM tracking is also very accurate for the same reason.
- The data at the end appears to show a GA from just below 100' AGL

......Which is all very inconsistent with the aircraft then crashing. Can this ADS-B data be considered accurate?

Those discussing the rising terrain upwind of the runway... Remember the crew is basing their GA decision on the Radio Altimeter at ~100' RA so even if they were well upwind of the correct touchdown point, the Rad Alt will still give you accurate ground separation for the GA decision.

If the crew were trying to grub-in below the weather.... there is no evidence of anything other than a continuous 3 deg descent followed by a GA.

I notice the ILS frequencies at both ends are identical. I wonder if some human error on the ground might present the correct localiser signal for 26 but a glideslope backbeam for the touchdown point of runway 08?

That would be more consistent with the trajectory of the accident aircraft.
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