What to do on a very windy day at Minden?
One exceptionally windy Sunday in August, approximately 220@21G25 early in the day and getting worse, everyone just fell out of the sky hugely annoyed because the strong wind completely obliterated the thermals, and lift was not to be found even underneath the clouds at 12.000ft. Both active runways 30/12 and 34/16 meant a serious cross-wind landing, so some of us decided to land on the closed runway – red “X”s be damned – the closed runway 21 was the best option because it was facing upwind.
Another solution to the problem was offered by a Soaring NV instructor and tow-pilot, Devin. He called Rwy 30 in the landing pattern. We watched from the air with great curiosity to see if he would get mangled by the wind, but clever Devin used the width of the staging apron in addition to the width of the runway to fly the imaginary centerline going diagonally across the apron and the runway, which was more appropriate for the wind direction. That was neat!
The soaring weather was not as strong on Labor Day Monday as the day before. After the first tow and the struggle over the Thermal Hill north of the airport I got low enough that I had to commit to landing. The airport was surrounded by sink, so I was aiming at the closed runway for awhile. Luckily, got some reprieve from the zero sink closer to the airport, and managed a much abbreviated pattern to rwy 30. Tow-plane that was behind me in the pattern had to land on the closed runway. He pulled up in front of me on rwy 30, quick hook-up for the unassisted take-off, and off I went for the second time. Spoilers popped open on take-off because I did not do a pre-takeoff check-list in all that excitement. To add further to the adrenalin rush and anxiety, I had to get off tow below 2000ft AGL again, and again struggle in the very narrow thermal surrounded by strong sink. Luckily, two gliders – one of them MX, our Mike S - were marking that thermal high above me, so it was easier to muster some motivation and stay with it. I caught up with them, and we eventually did some nice gaggle flying, and even a red-tail hawk joined right in front of my nose. Everyone was still fighting valley thermals around 2pm. Better performance gliders managed to finally get out of the valley, but I stayed and puttered around and enjoyed the view of Lake Tahoe for couple of hours.
Lack of oxygen makes me sleepy
On the last flight this late September, I had an overwhelming desire to take a nap, all of a sudden in the middle of the flight at 17.000ft. Even though I was tired from getting up ridiculously early that morning to drive to Minden, this felt different. Finally it crossed my mind to look at the oxygen flow-meter. Et voila! Even though the flow was set for 16-17.000 feet MSL some time before, the flow was back down to 10.000ft, probably due to regulator valve changing at cold temperatures at those altitudes. I adjusted it again for the 18.000 ft and it stayed there for the rest of the flight, and I was not sleepy anymore. I felt cheated: hypoxia-induced euphoria skipped me all together.
An earlier flight this summer, to Air Sailing and back
After I got my Silver Duration flight at the end of July, I wanted to have a dual flight in preparation for Silver Distance flight. The hope was for one really good cross-country day that would allow going north towards Air Sailing, thinking it would be a nice Silver Distance to go for eventually. And the day came on Aug 19 after almost two weeks of scattered t-storms and threatening over-development. With Mike S in the back seat, I went north past Air Sailing and back to Minden, topping at about 15.000 ft in between the clouds. The cloud streets going north made crossing the Dayton Valley and I-80 easier than usual. On a blue day there is appreciable sink in these two valleys as air funnels through them, especially on a day with strong westerly winds. One needs either a lot of altitude or a very nice cloud street in order to cross these “blue gaps” safely. There was still some rain and distinct smell in the air from the fires in the north around Lassen.
-- Maja Djurisic Stanford University Research Associate, Shatz Lab James H Clark Center 318 Campus Dr, W150 Stanford, CA, 94305 lab phone: 1 650 498 1970 e-mail: djurisic@stanford.edu
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