Sunday, June 3, 2012

Into Thin Air - Soaring To FL 250!

I almost cancelled my first trip to Minden, NV this season! What a mistake that would have been!

I was scheduled to fly with Devin Bargainnier in SoaringNV's Schempp-Hirth Duo Discus X on Saturday and Sunday, May 26th and 27th, 2012 (Memorial Day weekend). I had made all the arrangements several weeks in advance and as the trip approached, it became apparent that it was going to coincide with a late-season winter storm. A few days before the trip I was seriously considering rescheduling, but I decided to go ahead as planned as the forecast was indicating that the storm would be moving out by Saturday and I was thinking that it could be good post-frontal conditions.

When I left my house Friday morning to begin the journey, the Sonora Pass (my primary route) was closed due to snow and chains were required over the Carson Pass (my alternate route). So I grabbed my bag which contains all my cold weather gear just in case I was to encounter trouble on the drive over. I had no troubles getting there, just a bit of a slog getting over the Carson Pass. Chain restrictions had been lifted, but it was still snowing. I was stunned by the view that greeted me as I entered the Carson Valley and Highway 88 turned to run parallel with the Sierras. The storm was still raging in the Sierras and its clouds were spilling over the eastern escarpment like a series of waterfalls!

I was extremely disappointed Saturday morning when I awoke and the storm was still firmly planted over the Carson Valley. Cloud bases were low and it was raining in the Pine Nut mountains to the east and snowing in the Sierras to the west. Devin and I revised our meeting time at the airport for noon in the hopes that the storm would clear a little and provide more flyable conditions.

Things had not improved much when we met at noon. We assessed the situation and discussed our options. We could fly and most likely we would have a soaring flight as there was obviously plenty of energy in the atmosphere. But we probably weren't going to be able to get out of the Carson Valley because of the low cloud bases and a TFR in place at the south end of the valley due to a fire by Topaz Lake. We hemmed and hawed and Devin tried to convince me that I would be better off going fishing on Saturday and coming back on Sunday. I was tending to agree with him, but I wasn't ready to throw in the towel. I convinced him to wait another half hour before we made the final decision.

At 2:15 we went out front of the SoaringNV hangar and looked towards the Sierras to the west. I was already thinking about where I was going to go buy my annual fishing licence. Devin immediately proclaimed "let's go up in the wave". I looked at him incredulously and asked "really, do you think it's working"? All I saw was the storm clouds hanging about the sky. I saw no evidence of the classic lenticular clouds that usually mark the wave. He assured me that it was and I told him I'd be ready to go in 10 minutes. I was really thankful that I had grabbed my cold weather bag at the last minute!

We took off shortly after 2:30 and towed to the west. We encountered the rotor as expected, which was a really good sign that the wave was indeed working. I struggled to maintain position behind the tow plane as we towed through the rotor. It's like trying to maintain formation flight in a clothes dryer! Soon the turbulence was replaced by the smooth laminar flow of the wave and we released at about 9,000' (all altitudes are given in MSL).

Here we are shortly after release at about 10,000' and just beginning our climb in the wave. Again, absent were the tell-tale smooth lenticular clouds that I have come to expect with the wave and in their place was just a patchwork of ragged cumulus clouds.

Lake Tahoe came into view as we climbed above the cumulus clouds.

At this point we are climbing through 13,000' and the lift was strong enough that Devin presented me with two options. We could climb to 18,000' and stay at or below that altitude and proceed north to Reno, or we could see if the wave window could be opened allowing us to climb higher than 18,000'. I told Devin that it had always been one of my goals to one day climb above 20,000' in the wave. Devin radioed down to the SoaringNV office and asked them to call Oakland Center, the ATC center responsible for the area, and inquire about the possibility of opening the wave window.

It was interesting that the wave system was working differently on two levels this day because of a shift in the wind direction with altitude. The lower level was marked by the storm clouds, and the upper level was marked by the classic lenticular cloud at an angle to the lower level. The upper level seemed so much higher than us here that I somewhat jokingly stated to Devin that we might be able to climb into the upper level of the wave. Little did I know at the time that we were about to do just that!

A few minutes later the office called us back and informed us that the wave window would be opened at 3:10 after an airliner that was passing above us was clear of the area. The window would be open to 28,000' until 6:00.

Here we are after the window was opened and we are climbing through 20,000'. At one point above 20,000' we looked down and saw a Southwest jet beneath us heading to Reno.

We set our preliminary goal altitude at 25,000'. We would monitor the strength of the lift as we proceeded in the climb to determine if we would reach our goal, or go even higher.

Here we are climbing through 24,000' on a northwesterly heading. We are almost at the same height of the top of the lenticular cloud to our right, and we are way above all the cumulus clouds to our left. It truly felt like being on top of the world!

We reached our goal height of 25,000' in just a little more than an hour after takeoff. We had averaged a climb rate of about 300-400 fpm until about 24,500'. The climb rate dropped off to about 100 fpm for the last 500' of the climb and we decided we would not try to go higher. Spending excessive time at such extreme altitudes is just asking for trouble if something should go wrong with the oxygen system.

Note that the mechanical altimeter shows just below 25,000' and the more accurate GPS altimeter is reading 25,029'. We actually reached a maximum altitude of 25,060' before we began our descent.

The outside air temperature at this altitude was -40 degrees. You might ask, was that Fahrenheit or Celsius? And my answer would be, yes. That is because -40 degrees Fahrenheit equals -40 degrees Celsius. It is the only temperature that is the same in both scales.

As we began our descent, Devin cautioned me that we would not want to come down too quickly and put the glider through thermal shock as we descended into warmer air. If we did, the canopy could break. So we set the airspeed at 60 knots and I opened the dive brakes half way. This gave us our desired descent rate of 400-500 fpm. After a while, I released my grip on the dive brake handle slowly to see what it would do. Would it stay put, slam shut, or open fully? The dive brakes stayed deployed half way.

Everything was going well as we descended through 23,000' when all of a sudden there was a loud BANG! Surprisingly, this did not cause me undue concern as I immediately concluded that the dive brakes had slammed shut. But a quick look out and they were just where they had been all along. That's when Devin asked, "What the hell was that?" NOW I was concerned! A few seconds later Devin spotted what had caused the explosive noise. The canopy had broke! The very thing we were carefully trying to avoid had happened. You can see the crack in this photo. It is about 2-3 inches long running from the rear bottom of the vent window all the way to the bottom of the canopy.

The rest of the descent was uneventful. Once we got below 18,000', we encountered another glider climbing up in the wave. Can you spot it in this photo? 

We decided to fly north and went as far as Carson City. We then returned to the Carson Valley and flew around the valley for a little while admiring the views that the storm system provided.

After two hours in the air we were both sufficiently cold that we decided to call it a day.

I often post the GPS flight traces from my flights showing our flight route. However, it seems more appropriate to include the altitude plot from this flight.

In hindsight, I'm really glad I didn't listen to Devin and go fishing this day. I would have missed out on one of the best flights of my soaring career to date. Besides, the rivers are running high, fast, and cold this time of year. That could have been dangerous!

A very special thanks to all of the staff at SoaringNV who made this flight possible. Brad and Spencer for preparing the oxygen system. Spencer for getting the glider to the line and getting us launched. Patrick for the tow. Elizabeth for contacting Oakland Center to open the wave window. And most importantly, Laurie for not being too mad at us for breaking her glider a little! It truly takes a team effort to make a flight like this possible!

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