On Wednesday, September 26, 2018 at 8:12:39 PM UTC-7, Ramy wrote:
NTSB preliminary report:
https://app.ntsb.gov/pdfgenerator/Re...=HTML&IType=FA

2 to 3 seconds per loop? G'eeeees!!!

a = v^2/r so r = v^2/a. Based on a 40 knot stall speed, a glider would pull 9G before stalling at about 120 knots, 60 m/s. 9G is 88.2 m/s^2. So loop radius about 41m, circumference 256m, time for a loop 256/88.2 = 2.9 seconds. All neglecting gravity and speed increases and decreases.

Repeating for 10G gives 126 knots, 65 m/s, 43m radius, 4.16 seconds per loop.
Repeating for 8G gives 113 knots, 58 m/s, 43m radius, 4.7 seconds per loop.

Seems the paragliders' reports are plausible if they lost elevator control at a highish but nowhere hear Vne speed.

Ouch.