Flight Review

It's been quite a while since I have posted... and over two months since I have flown. January weekends were busy with family and organization commitments, and the weather was not so great. Then in February we had a death and two births in my immediate family, so weekends were again taken up. Lots of stuff happening with our soaring club, though... repairs, moving and working on equipment, and making plans for the future.

Private pilots need to have a "biennial" Flight Review (what we call a BFR) every two years, and mine expired in February. Another pilot and I scheduled ours for this weekend. It consists of an hour of ground instruction/quizzing, and an hour of flight instruction or three takeoffs and landings. The weather forecast was iffy for Saturday, with possibly high winds, but we all went up to Crystalaire hoping for the best. By the time we finished the ground meeting, the winds were 10-12 knots, pretty well aligned with the runway, so it was not a problem at all.

In the ground portion we talked a lot about emergency procedures, aeronautical decision making, and reviewed several serious accidents (one of which was a fatal crash by a friend of ours). We spent some time talking about optimal bank angles for minimizing altitude loss (45 degrees is best), and how that applies to low-altitude turns during  rope breaks etc., and how it applies in thermalling.

The other pilot decided he was not ready to do the flight portion of his review this day (he's not flown much lately), so the rest of the day was mine. I had never flown with this instructor before, so I was a bit nervous. It's not a pass-or-fail test, but it is still a critical review, and I always want to do well.

Flight #1 was a 3000' tow. I demonstrated imminent stall signs, and immediate recovery from stalls. We did several steep turns and measured the altitude loss, to confirm what we had discussed on the ground. When we were preparing to land, another glider had not cleared the runway and I had to discuss options for avoiding it. My plan was to overfly it and land long, but while we were on final approach the glider cleared out and we landed normally.

Flight #2 was a demonstration of tow plane signals which ended up with a downwind landing.

Flight #2 was intended to be a demonstration of a modified pattern, but based on our position relative to the field (and a too-hasty decision), it turned into a demonstration of a slip to a downwind landing.

My takeoffs, landings, stalls and turns were very good, but some of the other aspects of the flights resulted in some feedback from the instructor - that's why we do these reviews! We exchanged emails later that night to recap the day.

After we were all done, the other pilot and I removed the stabilizer from the ship. It has some significant  peeling and flaking of the top surfaces, so we are taking it to a shop to be refinished. That should take about two weeks, so we should have it flying again by early April.

Mind the gap!

Some places, that means "don't fall in the gap between the platform and the train." In soaring, that means "don't get trapped when the Foehn gap closes under you." I've learned about it in training and read about it, but never experienced it until today.

The RASPtable forecast showed possible wave from a southwest wind. The NWS forecast showed increasing cloudiness after noon in the high desert. Both were spot on! When I arrived at Crystalaire there were lennies far to the west, but it was clear overhead. By the time I was ready to fly, wispy wave clouds were starting to form over the local mountains. I had to wait quite a while for the tow, and we watched rotor clouds forming over the foothills, and increasing wave clouds over the mountains.




I launched at about 12:45 and there was only moderate rotor turbulence on tow. The tow pilot did a great job of dragging me right into the wave lift. When things got smooth, I let off at 7,800 MSL, which at 4,400 AGL was quite a high tow for me. But it worked! I worked the wave back and forth a bit, trying to find the strongest part. It did not form a very long line, and I had the best luck staying pretty stationary over the Devil's Punchbowl and facing into the wind. I bet my groundspeed was only 5 knots.

For quite a while, the only clouds were over the mountains. By the shape of the bottom sections, they were clearly driven by wind, but the tops were not smooth like classic lenticular clouds. There was some wind shear, with Hemlholtz waves visible occasionally. We had rain earlier this week and the mountains were dusted with snow, though not as much as I expected. There were a couple other gliders exploring the wave, but not very close to me. I eventually got to 12,200' MSL, much better than I expected today!




Secondary wave clouds started forming behind me over the desert. Initially they were pretty rough but eventually turned into classic lenticular clouds. Look how smooth the top of this one is. They look like static formations, but if you ever get a close look at the upwind edge you'll see it is constantly forming as the wind moves moist air up into it, and on the downwind edge it is constantly dissolving as the wind pushes the moist air down and it re-evaporates. The smooth top indicates the boundary of fast-flowing, condensed moisture.  You can see a gap called the "Foehn gap" between the trailing edge of the clouds over the mountains, and the secondary clouds over the desert.

The "standing waves" appear to keep the clouds in pretty much the same places for quite a while, but in  fact they are constantly evolving. The gap in the previous picture disappeared at its western end, as the two clouds merged. Over about a 5 to 10 minute period, that gap got smaller and gradually closed to the east - picture a zipper closing, with me as the pull-tab! I spotted it happening pretty early on, and headed east at a pretty good speed. I was actually higher than the clouds, probably by about 1,500 to 2,000 feet. I suppose I could have hopped over the northern (secondary) wave, but what if it developed even more to the north? So I continued east (in moderate lift, not losing altitude) until I was clear of it. This picture is looking back from where I came. See the narrow gap in the middle of the picture? That was much bigger 5 minutes earlier! I had heard about this phenomenon, so I was prepared for it, but I had never seen it in action.


Along the way, I saw a "cloud bow", a bull's-eye-shaped rainbow in thin clouds below me, with the sun behind me in the opposite direction. I tried to take pictures of it, but I only had a few seconds - and I was concentrating on getting out of the gap - so they didn't come out very well.


You can see the huge difference in cloud cover between picture 1 and picture 4. That cloud growth occurred in about 45 minutes! And hmm... now the cloud was covering the airport! If it grew much bigger, I'd be stuck above the clouds far from the field. I decided to duck under the cloud so I could be sure of getting back, even if that meant cutting my flight short. At this point I was still close to 12,000' MSL, and the cloud base was probably about 8,000' MSL, so I had a lot of altitude to lose. By a combination of speeding up to 80+ knots, and using spoilers, I got down under the clouds. But I had to fight quite a headwind to get back to the airport, which cost even more altitude. I didn't get very low, but low enough that I did not have much altitude left for exploring.

A couple of other gliders and I explored the area to the west of the airport, trying to reconnect with the lower part of the wave. It was there, but not wide enough or strong enough to let me go southwest far enough to really reach the leading edge of the cloud. So I eventually landed after just over an hour. By this time the clouds were covering 70% to 80% of the sky - just like NWS had said.

All in all, a very satisfying, interesting, and challenging flight.

How can there be lift EVERYWHERE?

I haven't posted for a while, though I have flown. Things have been pretty busy... I'll catch up on some recent events in the next post (I hope).

Today's forecast looked good, but with one caveat: NWS listed "broken cirrus" starting about 2:00 pm. "Broken" is a technical term that means more than half the sky. If that much cirrus came n, it could shut down ground heating. The soaring forecast showed a convergence of winds right across the top of the San Gabriel mountains - that would be good! Driving up from the south about 9:30, I could already see clouds right on the top, and it was way to early for them to be CU from thermal heating. The local instructor I usually check with said they had had great conditions for the last two weeks, and expected more of the same today.

I prepped the Grob 103. The gliderport was hosting a bunch of Boy Scouts flights... between those, a down towplane, a wind shift which meant towing six gliders to the west end of the runway, and a line mixup, I didn't launch until 1:45. Fortunately the cirrus was staying scattered. The lower clouds looked great - more over the mountains than the desert, and cycling fast enough you could tell new ones (good lift) from old ones.

On tow, we had an "event" - I don't know if you'd call it a close call or not. After takeoff we did a 270-degree turn to head south. That took us over the downwind leg for the opposite-direction runway. Fairly abruptly, the towplane climbed, not the typical flying-through-lift jump - and I had to catch up. Looking down, I saw a glider on downwind leg about 100-200 feet below us. I don't know if it caught the tow pilot by surprise and this was "evasive action" or whether he had him well in sight... but it was closer than I've ever come to another glider while on tow.

I let off at 2700' AGL (6100' MSL) in good lift. I found good stuff right away, and took successive thermals up to 8,000, 9,500, and then 10,600 over the mountains. I overflew Mt. Baden-Powell, then went chasing ever higher clouds.

 

Some like the ones above looked nice and sharp on top, which indicated they were growing and would have lift underneath. But they were cycling so fast that they died before I got to them.

In the next pic you can see I'm close up under some smaller ones. The trick was to look for wisps of moisture that were just starting to condense, and quickly get under them.






The highest I could get was about 11,000 MSL under these clouds. I very rarely hit any serious sink between patches of lift. Eventually I headed out over the desert and... the lift got even better. Away from the mountains, with their moist lift, it was all blue, but there were long straight stretches that I assume were convergence lift. I went probably ten miles straight north and was usually in zero sink or minor lift. Eventually I reached some little lakes and I was still at 10,000+. Then... I hit even MORE thermal lift (with no cloud to mark it) and worked that up to 12,500! This was probably the first time I've found a higher lift ceiling over the desert than over the mountains. It really felt like the lift was EVERYWHERE today. That's not usually possible - what goes up must come down - but if there was a large-scale convergence due to the south wind coming over the mountains, colliding with the mild offshore wind that was building, maybe there was a widespread general uplift in addition to the great thermals.

I decided to come in after about two hours of great flying, and had to use spoilers to get down from 10,000 feet! As I got down near our "report-in" altitude of 5000' MSL, I could see there was a glider staging for takeoff, and a glider on the radio was getting ready to land. Now usually, we have limited ability to go into a "holding pattern", but as I circled just to the west of the airport, I found a wide, gentle thermal. I held there for 10-15 minutes while one glider took off and three landed - and I had gained 1,500' without even trying. Highly unusual!

I ended up with a total flight time of 2 hours and 25 minutes. Everyone I talked to on the ground agreed it was a terrific day for lift.

Friday the 13th? Bah! But still....

I read quite a few publications about flying, not just soaring, because I want to be the best pilot I can be.  It's frequently stated that many accidents come about not because of a catastrophic event, but because of a "chain" of things that lead to a bad situation or bad decision. These things can be actual problems, or issues that stay on the pilot's mind and cause distractions. I try to be very self-aware and keep an eye out for multiple things going wrong. Many of these are just normal things that crop up during flight planning and prep, but some days more of them happen than usual. That doesn't necessarily mean I won't fly, but it makes my "spidey-sense" go on high alert and make sure I'm being extra careful.

I'm not superstitious, but this series of unfortunate events started the night of Friday the 13th.

• I thought I was going to have a passenger going for an intro flight on Saturday. That's fine, I like giving rides. He was on and off all evening. He wouldn't get to the gliderport until noon, which meant no smooth early ride, and possibly waiting in line for a towplane if we took off during prime time. It doesn't really make much difference, but it meant I needed to think about which plane to prep, what time to fly, whether anyone else would need the 2-seater, etc.
• I found that my PDA (an old HP iPAQ) had lost its memory. That's happened a few times before, usually due to failure to charge the battery in time. But this time the battery and charger were OK, so it's unexplained. Because I have changed computers since the last time this happened, I had to mess around a bit to get the programs and files installed, rather than running a simple restore. And then had to test the GPS to make sure it was working. This took well into the late hours of the evening.

Saturday, before flying, stuff kept happening:

• I got a text message that the passenger had decided not to go. The message was from 2:30 in the morning. So I'm wondering: what's up with that? Oh well, at least I'll get to fly the PW5, which is easier to prep and simpler to fly on what was looking to be a good thermal day.
• During the preflight inspection, an issue came up with the PW5. I won't go into it here, but it caused me some delay and concern as I had to walk around and search both ships and both trailers, and contact the most recent pilot to ask about it. His phone number had changed, but I contacted him by text message and later talked to him. More extra tasks and delay and distraction.
• I usually use my own O2 tank with the PW5's electronic system. Once before, and again today, I could not get the PW5's screw-on connector to seal right, which means O2 leaks out. Probably we need to replace the O-ring again. After trying for quite a while, I decided to use my own Oxymiser system, which means removing the PW5's box and tubing. That's pretty simple, but it does mean using a manual flow control instead having the automatic system come on at 10,000 feet.
• I started up my PDA/GPS and it got a good fix. Whew! Last time it didn't, and I didn't get a flight trace. But a few minutes later it popped up the screen demanding the license key (since I had reinstalled SeeYou Mobile last night). Fortunately I have that key in a text file on the device. Unfortunately cut-n-paste wouldn't work, so I had to write down and enter the key manually. Just another annoyance... in 90+ degree heat...

I nearly always take a break after the inspection and prep, have my light lunch, cool down, and then go fly. When I get back to the ship, there are always a few final items to take care of, because I don't like to put certain things into the cockpit because they get hot. When I was nearly ready, I found I needed to make yet another trip back to the "pilot's lounge". On the walk back to the plane I reviewed all the distractions and delays, and decided that they had not accumulated into anything that would keep me from flying. As I mentioned, I'm aware of cumulative distractions, but all these items had been resolved, so I put them out of my mind and focused for the flight. The CU's had been popping since 9:00 but were not overdeveloping, so it looked to be a good day. I took off at 12:45.

Stuff kept happening:

• During the tow, the red emergency canopy release handle fell off. Just fell off! I ignored it and focused on the tow, which is a critical part of the flight. I didn't need to be feeling around my feet looking for it while flying formation! Later in the flight, I found that it had nicely landed on the pedestal within easy reach, and it simply screwed back on.
• Once I started thermaling, I noticed that the "thermal analyzer" function of SeeYou was not activating. That made me wonder what other settings might not be set the way I wanted, but nothing else arose during the flight.
• I received a pulse oximeter for Christmas, but had only tried it once before in flight. This time I tried it again, but I could not see the display and put it away. Later on the ground I saw that it was not detecting my finger. I tried it later at home and it worked fine. Maybe I didn't put it on right, or maybe it got overheated? Another distraction...

All that aside, it turned out to be an outstanding day for soaring! I let off tow in lift and never lost it. Very quickly I got up to 10,000' MSL and never went below that altitude until it was time to come home. Most of the time I was above 11,000, and my max was 12,776. 

The CU's coming off the northern edge of the mountains were abundant, close enough to nearly form "cloud streets" at times. 

The lift was turbulent, though, with lots of ups and downs. This flight trace is color-coded by vertical speed. It's really rare to see the lift and sink so interleaved. 

The CU were not big or strong enough to overdevelop into thunderstorms in this region. I could see to the east that there was a whole north-south line of bigger CU. In the picture you can see that it's hazy brown below the cloudbase, and clear above. (Click on the pic for a better look.) I think there was a convergence of air masses triggering those CU's, different from the ones where I was which seemed to be thermally generated.

And the lift was not just under the clouds, I found lift between them that allowed me to go higher than the cloudbase. This was probably the best thermal lift day I've experienced since coming to Crystal. I didn't really go very far - I've written before about the limitations of flying club planes - but I did go further west and north than I ever have. Someday I'll map out a local cross-country triangle and do some goal-oriented flights. For now I'm just having great fun cloud-hopping at 12,000 feet!

I also went north over the desert and continued to find lift to 10 thousand feet. I flew for nearly two and a half hours. It would not have been a good day for my passenger's intro flight - we would have had to start much earlier in the day when it was not so turbulent.

Weird but it Worked

Sunday's forecast was for winds from the west or northwest north of the mountains, but from the south down in the L.A. basin. That made for a possible convergence at right angles right on the top of the mountains. It looked like there could be the possibility of mountain wave lift in places. It was warm enough for some thermal heating too, if the winds did not blow them out.

I decided to fly our Grob 103 Twin Astir because I wanted to check out some issues with how it handles. Our club members have been discussing how heavy the aileron controls are, and whether the stick forces are increasing or not. (If any readers have experience with this in Twin Astirs, I'd like to hear about it. This specific model is known to be different from other Grob 103 variants.) Since the winds were fairly light, I figured it would be a good day to experiment with it.

There were reports that lift was working well over Mt. Lewis. I towed to 3900' AGL (7300' MSL) over the "second ridge" and let off in decent lift, hoping to work my way up to the higher mountains. It was pretty patchy lift, though, and I had to drift down the ridge (westward) to keep sufficient clearance. I found more lift over the valley next to the Devil's Punchbowl than I did over the hills. It was enough to slowly creep up, but nothing very exciting. A couple of other gliders joined me, but none of us were climbing very fast. For the first hour I was up and down by just a few hundred feet.

The lift was puzzling, as it often can be in this area. Sometimes it was too narrow to circle like a thermal, and there was rotor-like turbulence next to it, but the lift was not smooth as one would expect if it was wave. For a while it seemed to be parallel to the second ridge, as if it was a small wave coming off of it, but other times it was perpendicular to it.

After about an hour of hard work, I found a big, wide area of lift that felt more like thermal, and shared it with (as I later learned) a DG-400. That is really one of the fun parts of local soaring: flying near, but not too near, other sailplanes. Watching each other swoop and turn big lazy circles, or tighter turns trying to core a thermal, you feel like you're weightless, and the ground far below is irrelevant. It's amazing how suddenly your companion glider can be a couple hundred feet above or below you, as you each get into and out of areas of lift and sink. Unfortunately I did not bring my camera along this time.

One of the great thrills is finally "ratcheting up" the altitude and finding that you're going up more than going down, and being able to relax and enjoy the flight. Eventually the lift was stronger and more consistent and I reached 9,000' MSL. By that time I had been up for nearly two hours, and I had kind of a time limit to the afternoon, so I called it a day. Not a spectacular day, but ultimately a successful one. I ended up with a total time of 2:08.

Talking with other pilots back on the ground, we all agreed it was a weird day. Some lucky pilots broke through to some good wave lift over the higher mountains and got to 14,000'. Others of us in thermal  lift topped out about 9,000'. Some of the lift was hard to categorize, so we figured it was some combination of convergence and moderate wave over the hills, and thermal over the flats. Whatever!!