I've just come back from 4 days at the NSA Bishop encampment,. What an experience flying the Whites! Unbelievable thermals (one went to 17,800') and even a bit of wave to 18,000'.
I didn't get chance to drive to Schulman Grove, but I did give the visitors there a close up (and I mean really close up) view of my glider as I rode the thermal ridge lift at their eye level.
'Impressive' is the understatement of the year!
Although I never needed a relight on the four days I flew there, on three of the days I released too early in what I thought was good lift, only to find myself scratching round at 5,800' - 6,000' for 1/2 an hour to an hour trying to find the elevator to take me to the top (I believe my tow costs were the lowest for those four days). That in itself was a learning experience - doing short, figure-of-eight beats of perhaps 1/4 mile in length, just a couple of hundred feet above ground (airport still within glide, of course), just to stay airborne. Of course, once decent lift was found, it was no trouble getting to the ridge line. People often talk about ten-knot thermals when in fact they're really only ten knots (an optimistic maybe) for a short duration. Well, in one thermal, my averager showed a minimum of ten knots+ for two minutes straight! Unbelievable!
The other quite amazing learning experience (common knowledge to power pilots, of course) is the effect of altitude on true airspeed. Since most of the flying on the Whites is above 12,000', a glider's true airspeed can be quite remarkable - and hence the need for extra vigilance in the lookout for other gliders and also being cognizant of the glider's design limits in the sometimes turbulent conditions. It is easily possible for two gliders to be approaching head-on at closing speeds approaching 250 knots. The lesson is - use your radio frequently, give position reports and keep your eyes out of the cockpit. On the day I contacted wave (oh, so smooth), west of Bishop, I initially burned off my 17,999 feet of legal altitude at about 140 kts true airspeed (it was my turn to be cook for the barbecue that night!).
Incidentally, and it didn't seem to matter, anyway, there was no cumulus on the Whites to mark the lift during those four days. Once you were on top of the ridge and running in the clear blue sky, it was easy to find thermals just by flying along the ridge, from peak to peak.
All-in-all an experience not to be forgotten and one I hope to repeat in years to come.
Cheers,
Terry Lowe.
