Monday, April 18, 2011

Thermal Season Begins with Passenger Flights

My cousin R and his wife J have been wanting to go soaring for a while now, and I've been waiting for the thermal season to begin so I could give them more than a "sled ride". Well, it's been warming up in the high desert, and reports out of Crystalaire have indicated that the thermals were popping the previous weekend, so things were looking up. We headed out there on Saturday. (The forecast high temperature was 87F.) As it turned out, no one else in the club was planning to fly the Grob that day, so I was able to take my time and show them all aspects of the ship as we washed and inspected and prepped it. Both had been in small planes before, so they were interested and eager.

The Grob had had some maintenance done on it earlier in the week, so I took it up for a checkout flight to pattern altitude before flying with passengers. Although it was well before noon, there were little bumps on tow, so it looked like things would heat up. I tried for a precision landing right on the numbers, and bounced the landing - haven't done THAT in a long time.

We had lunch and waited for a few others to stay up so we'd be pretty sure the thermals were working. J and I took off about 1:10, took a 3,000' tow and let off over the Second Ridge (there were some decent bumps on tow). We didn't find much there over the hills, and I'm new enough to this area that I didn't want to get too low, so pretty soon we headed out over the desert.
We found a couple of other gliders that were climbing, so we slipped in underneath them. I had explained earlier that this was one of the fun aspects of soaring: flying in a "gaggle" with other gliders. We worked it for a while and were able to gain a thousand feet. I kept checking to see if J was OK with the circling, and she was doing just fine. This thermal seemed to top out at 6,000' MSL, so we went looking for others. Didn't find any... came back to this first one... and it was no longer working. I never did find more lift in the region, so we came back in, for a total flight time of 42 minutes. That's probably about right for a first glider flight anyway. This time my landing was smooth, that is until turning off the runway into the stopping area. Wow, that dirt area is rough!

R was up next, and we took off just about one hour after the first launch. Things had heated up, and we felt a bit more turbulence on tow, but not bad. R video'd the takeoff and tow. This time I held on a little longer, and we towed further up the Second Ridge until we found some good lift. This tow was about 3,500' AGL. We immediately climbed about 500' in 2-3 knot lift. Not bad, but nothing spectacular. It seemed kind of disorganized, and I couldn't find more than 1 knot over the hills after topping out that first thermal. Not much over First Ridge or the punchbowl either, so once again we headed for the "house thermal" west of the airport. There we met up again with two other gliders, so R also got to fly in a gaggle, and was a great help keeping the others in sight. R also was not bothered by the circling. (I've written before about how passenger flights are sometimes a difficult balance between circling to stay aloft, and trying to have a gentle flight to avoid causing airsickness.)

We were working the thermal pretty well, when suddenly my portable radio "jumped" and landed down by my foot. Since I was flying from the rear seat to give my passengers the better view, I could not use the glider's built-in radio (there's only a boom mic in the front seat), so I was using my handheld, my headset, and my Velcro-attached push-to-talk switch. I have a wide Velcro strap that goes around my leg, and the radio's belt clip goes on the strap. Well, the belt clip on the newer, larger battery pack is a little smaller and does not clip firmly on the strap. It's never caused a problem until today, when it crept off the strap and fell down in the footwell. As soon as this happened I straightened out and left the thermal to deal with the radio. It was j-u-s-t out of reach - you can't lean forward in a four-point harness. Fortunately gliders can fly pretty well by themselves for short periods of time, so I trimmed it for minimum sink speed, leveled the wings, centered the rudder and went hands-off and feet-off. Also fortunately, there was no traffic in the direction we were gliding, but I still had to keep a lookout. I was beginning to think I was going to have to unstrap, when I finally got it by the antenna. By the time I got it back in place and plugged in, and dealt with another couple of distractions, we had lost a few hundred feet out of this already fairly weak thermal.

We cruised all around the airport area, even tried to poach off another glider, but he wasn't climbing either. We didn't find any more lift, so we came in for a smooth landing at - how about that? - 42 minutes, same as the previous flight.

Once on the ground, I checked with a few other pilots and several said the same thing: we found one good thermal to keep us up for a while, then nothing.

So, all in all it was a fun day. Both of my cousins enjoyed their intro flights, and we were able to thermal long enough for them to get some idea of why we crazy sailplane pilots keep coming back for more.

Sunday, April 17, 2011

Flight trace video of my wave flight

I sometimes record traces of my flights with the SeeYou Mobile program running on an iPaq. I then play them back on the SeeYou PC program to study how things went. I've recorded a playback of my April 2 wave flight and posted it on YouTube - first time I've figured out how to do that. It's played back at 10 times the actual speed, so my 2 hour and 20 minute flight plays back in 14 minutes. Here's the link.

If you just want to see the time when I really connected with the lift and started climbing at a good rate, go to 8:05 through 11:42 in the movie (which is about 13:42 to 14:18 on the flight clock).

Wednesday, April 13, 2011

Blanik L13 Testing and Modification Plan Completed

Great news! A plan is now in place for inspecting and altering the Blanik L13 structure to determine which aircraft can be returned to service. The proposal has been submitted to the EASA and FAA, and the first few gliders have returned to the air in Europe. Details are available here and here. No info yet on the cost of the program.

Saturday, April 02, 2011

Great First Solo Wave Flight

Today a weak front was causing a southwest-to-northeast flow, which made for mountain wave conditions at Crystalaire - the first day it's actually been working since the day of my site intro flight. There were monster wave clouds, closer to the airport than I had seen before, probably too high to be of use to us, but indicating good wave action. As I was prepping the PW5, Dale (very experienced instructor) came over to give me some advice on how to fly the wave today. That was nice - I was going to seek him out! He thought it was weakening today and not likely to go over about 8,000 to 9,000 feet, with maybe some thermal lift later in the day if the cloud cover was not too thick.
I took off at 12:20 and we towed through rotor on the way to wave lift. A high tow was necessary to get there, and I let off at about 8,500 MSL when the rotor abruptly quit. I was immediately in weak to moderate wave lift. I worked it for a while, trying the areas where people had said it had been working a little while ago. I found up to about 3.3 knots of lift in the beginning. I gained some, lost some, in it sometimes, in sink sometimes - worked between 6,700 and 8,800 for quite a while, feeling it out and trying to figure out exactly where it was. Every time I got back into a little rotor, I headed back upwind and found wave lift. It wasn't very wide, so I had to go back and forth in a fairly narrow "sweet spot". A couple times I found *heavy* sink as I got too close to the mountain, as expected (since the wind was "spilling" downslope before it bounced back up again).

A couple times I decided to head back to the flatlands, and when I went over the "second ridge" I contacted even stronger lift. At times it was up to 7.7 knots! (Later I was reminded that the waves tend to move downwind over time.) I finally got smart and realized I needed to turn back sharply when the lift started to weaken, so I could get right back to the good stuff. This worked really well, and I worked it up... and up... topping out at 10,200 feet. Another pilot worked it from 10 up to 11 while I was there, and Dale got to 14!

In this flight trace, the later part is in the upper left, and you can see how much tighter I was making my back-and-forth passes.

(Click on the image to see the full-sized picture.)

As many people have said, the lift in the wave is incredibly smooth. At times there's almost no sensation of motion if you're headed into the wind. In this next trace, the line color shows groundspeed. There were times when my GS was as little as 17 knots.

After about two hours I decided to come down. On the way back to the airport I continued to find lift up to 10,200, but also some pretty hard rotor. I eventually pulled 1/3 spoilers and turned lots of circles to get down. The lift was so strong and easy to find I could have stayed up a long time.

Approach and landing were challenging. I called in for a wind report, and was told it was from the southeast at 15 with stronger gusts, so I chose to land on runway 7 (to the east). On the way into the pattern I continued to get battered by turbulence, a couple of those big bumps that knock everything around in the cockpit and lift you out of the seat even with the belts tight. On short final I got a couple more fairly hard bumps. I carried some extra speed due to the expected headwind component, so I was able to control it pretty well, but once I got down low I put it down as soon as I could - no floating in ground effect - I wanted to be on the ground! Once I started to slow down a bit, I found out how strong that crosswind really was. It turned me about 45 degrees to the right and off the runway. (The PW5 has a decent sized tail but a tiny rudder, so crosswinds really push it around.) I applied full spoilers and wheel brake and stopped just a few feet to the side of the runway.My wings were level, or I should say right wing down a bit because of the crosswind, so I don't think I even came close to touching a wing. But it sure turned me!

Later the fellow who gave me the wind check said that although the wind sock showed it to be from the southeast, when he stepped outside a few minutes later he saw how cross it was. By that time I was committed to 7. Some other folks pointed out that there is a dirt crosswind runway which would have been much more into the wind, and in fact someone landed on it moments later.

So although I landed safely, I learned two big lessons:
  1. Even with a wind report from the ground, make sure to look at the wind socks or tetrahedron for confirmation. I was approaching the field perpendicularly, so I knew by the time I could see the socks I would be really close and need to commit to a direction, so I relied on the report. And I was dealing with a lot of turbulence and a strong headwind, so I really didn't plan for or have enough altitude to overfly the field.
  2. Know all of the resources available. Even if I had known how cross the wind was, I really had not thought about the value of that other dirt runway. I chose between 7 and 25 based on the wind direction, but I did have another option which would have been better.
My flight was 2 hours and 20 minutes, and up to 10,200 feet MSL. Not bad for my first day of surfing the mountain wave.