Friday, November 5, 2010

High Altitude Glider Flight

4 Sep 2010
Even as the sun rose that morning, it looked like an excellent soaring day. I was dressed for summer operations. I was wearing my VFF shoes (clearly designed for summer), shorts, and a tee-shirt. Several people quipped that there might be wave lift, due to the westerly winds. There was likely also ridge lift. There were incredibly strong thermals early in the day, and even if the wave or ridge lift were not working, it would still be a great day to be a glider pilot.

On a lark, I packed the "new" oxygen system in the glider, and hooked up the cannula. Three years ago, I bought this oxygen system shortly before I found that I was being relocated to Switzerland. Due to the timing of the equipment purchase and the relocation, I had never made use of the oxygen system. It was a shame to buy this brand new toy, and never be able to use it for over three years!

I hooked up the oxygen system to the Mountain High regulator, and hooked up the cannula to my face. Psst! Yep! It smelled like oxygen that has been in a bottle for over a year. After some tow-rope-break-induced delays, I launched later than I had originally anticipated, donning my summer-clothes and cannula.

I immediately connected with some intensely strong thermals. In only a few minutes, I was up to 500 feet below cloud base at around 7 or 8000 feet. I started nosing around for what had to be wave. I hung around on the upwind side of the clouds, and aggressively worked any gusts. In this situation, my standard procedure of waiting for the vario to drop off before starting to turn takes too long -- the lift is too spotty and broken and disjointed right under a rotor cloud to use regular thermalling techniques. So I just treat it like "really aggressive thermalling", and turn at the first indication of a gust of lift.

It didn't take long, and I connected with the wave, just over the eastern ridge of the Massanutten, east of Fort Valley. In short order, I climbed above cloud base at a steady 2 knots, still not expecting this to be a great wave day. (At least it's nice to get above the clouds!) The duty officer called Potomac Tracon, who had cleared the airspace of all jet liners, and said we were OK to climb to 18,000 feet without worrying about conflicts with the jet liners. By this time, I was climbing through 10,000 feet, and almost at the top of the clouds.

I continued to head south toward Luray, where Jim Kellett joined me in the wave (but not for long). As far as I could tell, we were the only two people within radio contact to get into the wave on that day. The key to working this day's wave was patience. Since I didn't have anywhere to go, I had all day. Eventually, I climbed above 14,000 feet -- higher than I had ever climbed before. The oxygen system was working perfectly, filling my nostrils with oxygen-bottle scented air. The Mountain High regulator has a pressure sensor, which determines how much "puff" of oxygen to deliver to the cannula. The quantity of puff is based on your altitude. On the ground, it is not much more than a 'token puff', as I continued to climb, the puffs became more substantial.

Several times, I had decided that "this has to be the top of the lift" and almost gave up. It was not terribly cold at 14,000 feet, and since I was above the clouds, the sunshine was keeping me quite warm. I headed a bit more upwind, to the southern corner of Fort Valley. There, I connected with a solid 4 knot lift that took me all the way to 17,600 feet. I had decided beforehand to cut-out at 17,500 feet of altitude -- just to have some margin of safety so I wouldn't break into Class A airspace inadvertently. I made a quick recording of this part of the flight with my Blackberry camera-phone, and headed south toward Harrisonburg. The flight computer showed the outside air temperature at 20 F.

The flight toward Harrisonburg was slightly upwind, and I wasn't overly concerned about finding lift along the way. By the time I got to just north of Harrisonburg, I was just over 10,000 feet, approximately as high as the clouds. Time was growing short -- a schedule of returning in time to disassemble and get to the Flight Instructors' caucus was drawing near. I headed directly back to Front Royal, aided by a tail-wind, with a ground-speed averaging 110 knots, even though I only had 80 knots indicated. My return flight to Front Royal cost me only about 1000 feet. Apparently, on the return trip, I must have been riding the wave, or at least minimizing the time-in-sink along the way.

Along the way back, I flew close enough to a cloud to see the effect called "Glory"

What a day! Unfortunately, we (the owners of the glider Juliet Sierra) are having a little problem with our Volkslogger. It records -- most of the time. Other times it gets tired and doesn't want to look up to the sky to see the satellites to get its position. It is a good thing that I already have my FAI Gold Badge, and that I wasn't setting out for a badge flight of any sort. As for evidence of my flight? Since the Volkslogger wasn' t working, there was no suitable proof of my flight, other than my word for it. (I did get my GPS watch to record most of the flight, though). I wasn't able to upload the flight to the OLC, due to the fact that I didn't logging the flight with my GPS watch until I was airborne and on tow.

Here's a picture of the flight in Google Earth, (Click to get a better view) as viewed from an oblique angle, looking down from 33 miles of altitude. The black shadow is the ground track along the flight. The colored ribbon is for my position, Yellow, orange and red are for various rates of descending flight, blue is steady or climbing flight 0-2 knots. Light-green indicates slightly descending at around 0-3 knots. I put a thumb-tack to indicate where I achieved the maximum altitude over the ground.


Hugh said...

Way cool! Can't wait to leave the bubble around KFRR (couple more sign offs to get - gotta learn how to assemble/disassemble/trailer club gliders). Can't believe you did this in shorts and a t-shirt - that solar-cooker canopy really works. As someone said "the more I fly, the luckier I get". - Hugh

Anonymous said...

Thanks for posting Pete. It gives everyone a good idea of what to expect in Wave. Again, thanks for sharing. Greg