Originally Posted by
cappt
With poor airspeed control and a conservative glide/ratio they would have had a good 30 miles of glide from FL210.
They almost hit the VOR RNG which is at 8700 ft MSL, 10 nm out of the threshold. If the information is correct that they started descent at 17 nm out, that gives you a glide ratio of 1:3.5 which is probably about 1/3 of what is achievable.
I think the theory that they were mistakenly attempting to descend to the VOR seems quite plausible. If the last range they had read was to the VOR and when EFIS quit, they might have though they were too high and configured for a steeper gliding descent than necessary.