11-07-18 A Finicky Wave

November 7th, 2018 had a promising forecast. The front would have passed many hours previously and the upper air mass set up the stability and winds conducive for wave. It was a bit trickier day than the previous explorations. Skysight had the wave a hair weaker, the wind was quite strong (55 knots or so at 8000ft) and there was a little bit of shear at altitude, with the wind shifting from 280 degrees in the inversion to about 250 at altitude. All of these variables will factor in the day.

I like Steve Lenter. Several times he enthusiastically mentioned his interest in soaring the Catskill wave. On Monday when I figured that the forecast was workable, I gave him a call and asked if he would join me on a wave mission Wednesday morning. My class was planned in the late afternoon, so I could sneak in and make a flight and come back. Steve dropped all of his plans and said he’d be there. Gus Johnson lent him an oxygen system (thanks!) and Warren said he’d be ready to tow us. We agreed to arrive at the airport no later than 7:30am to get the K-21 equipped for our flight.

A little after 9am, we were on our way. There was hardly any wind on the surface and yet the wind quickly gained strength with altitude. The ridge was working and Warren powered back for a slower climb toward Ellenville. We were then in the curious condition where both the towplane and glider were ridge soaring along the ridge lift. The K-21 was trying to catch up to the towplane! I stayed out to the left side of the towplane, hand on the brakes to avoid developing too much slack in the line. I had never had to deal with so much slack for so long! We tried low tow, but that simply made the bow in the line get above the wing, which was a bit disconcerting. I went back to normal tow where it was more comfortable and kept the bowline in check.

Once we got to Ellenville, we started climbing toward the Catskills. Once at 4,500ft, the air went perfectly still, we were now in the inversion. Ahhh, sit back, relax and enjoy the flight! I gave Steve Lenter the controls and whipped out my trusty Garmin GPS. I had dialed in the turnpoint where I expected the wave to be and guided Warren along the course. We had a 45-degree crab angle thanks to the unbelievably strong winds aloft. They were easily 60 mph and we were hardly making headway. The good news is that since we were above the boundary layer, there was no turbulence to speak of.

Just on the western edge of the Ashokan Reservoir, right by Boiceville, we found weak wave. We released at 6300ft and started climbing at 1 knot. Not quite as strong as the last few times, but we will make do. At the time, I figured we may have just missed the sweet spot, that it was stronger elsewhere. But since I had one knot, I was going to stick with it to get some buffer. Certainly at release altitude and much below 9000ft, Kingston Airport was the only good out to deviate to. It was 15 miles away, but straight downwind. There are also fields along the way should there be unbelievably strong sink, but nonetheless a 60 mph tailwind should be good for something. I believe 6000ft is a very reasonable margin for the K-21. But Ellenville is 18 miles away, with a crosswind bordering on a quartering headwind. Much trickier to get to. 9000ft would be a reasonable altitude to attempt a return.

I wanted to get at least to 8000ft, but preferably 9000ft before getting cute and start moseying around in the wave. The challenge with such weak wave is that if you get out of position, especially downwind, it will require putting the nose down and sinking faster to reconnect. When you have little margin to begin with, normally I would hold my breath until I get to 9000ft, get my oxygen on and finally relax. It’s kind of like finding that first thermal off of tow, especially in a glider competition. Get high enough to establish yourself and feel connected and then think about the next step or how you could do better.

But this time, the wave was painfully weak. 1.3 knots was the best we had and often times it was .5. Patience, patience, patience. It is likely to get better higher. In the beginning, I was going through my patter as to what I was doing. About 15 minutes in, I shut up and concentrated. Steve was quiet too, but when I would ask how he was doing, he would enthusiastically say he was fine! I’m glad he’s okay back there.

We clawed our way through 8000ft, gently searching around for little bits and pieces of better wave. This persisted through 8500ft, where the wind sped up and the lift got just a bit chopped up. We were maintaining 62 knots indicated to maintain position and we weren’t climbing anymore. I made a bigger searching pattern, not to find any stronger lift. We then fell back a bit in the wave, found a 1 knot area up to 8300ft and it weakened again. It was past 11am and the wave was predicted to weaken. We are not going to do any better.

The big question now was Kingston or Ellenville? I could see Ellenville out the window and it was very tempting. I reconciled the temptation by stating that the distance to Kingston was not going to increase if I headed toward Ellenville first and I could bail toward the alternate at 6000ft. So we headed out, encountered very weak wave which improved the glide angle. Ellenville fell in view. The pressure was on. Do we keep going or deviate?

The glide to Ellenville kept improving. The needle hits 6000ft. Let’s keep going.

At this point we were in neutral air, humming along at 75 knots. The wind was ferocious and the glide angle is holding on. The Garmin says we are doing 17-1 and need 9-1 to make it. Down into the boundary layer we go and we hit some sink. This sink won’t persist! And it doesn’t, angle improving once more. But man, with this wind any sink you hit is like throwing out a drogue chute!

We made Ellenville at 2500ft MSL and I let out a big sigh of relief. I tested the ridge to see if it was still working, but the wind had shifted too much. Having gotten out of the doghouse, I had no intention of clawing my way in marginal ridge lift and made a beautiful landing on the pavement at Ellenville.

Joe Bennis came out to greet us and help ground handle the glider. Thanks Joe! We waited for the L-19 to retrieve us. This time, Rachel Conklin came to our rescue and towed us back home. She is such a great towpilot, incredibly smooth on the controls. The K-21 released so lightly that it hardly tugged on the rope. She didn’t notice we were off and I found some weak lift in the valley. This made for a rather comical 20 seconds, where I was off of Rachel’s right wing, pretty much at the same altitude and speed! Then she noticed that the glider was gone and dipped down to land.

Another nice landing and we had the glider put away a little after noon. What an exciting day of soaring!

We learned a lot about how the wave sets up and for safety in future wave operations. With every flight, we are getting a better and better sense as to how the models perform relative to reality. The wave was there and almost exactly where Skysight predicted it. But the wind strength being so high flattened it out a bit, which made it a bit weaker than expected. Thanks to the directional shear at 8500ft, we just couldn’t climb through the weaker spot and got stuck. All very useful information for the future! And lastly, having had to deal with the escape was also valuable for safe wave operations.

Thanks John Bird for helping with the wave forecast! Thanks Warren Cramer and Rachel Conklin for towing us today and lending the K-21 for wave flying. And thanks Steve Lenter for joining me on this wave soaring expedition!

Find the flight log here.

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