Sunday, May 18, 2008

A Weird Flight

This should have been a great day. I'm still trying to figure out whether I was just off, or just unlucky, or whether there was something wrong with the aircraft.

We're in a heat wave, but the temperatures aloft were good, so the thermal forecast looked great. I forecast a thermal index of -3 at 5000' MSL, and thermals to 10,000'. The NWS thermal forecast was even more optimistic: 1100 feet/minute to over 14,000'. As I was driving in, I could see CU popping over the San Bernadino mountains to the north at 10:30. They were popping all around the Hemet valley, and over San Jacinto by 11:30, though small. I planned my flight as if I were going to the top - took all my cross-country gear. This would be the first time I used the EDS oxygen system that we just installed. I swapped my O2 tank for the club's tank.

It was hot. Forecast was 101F. When I pushed out it was 108. "But it's a dry heat." That's really true... 108 at Hemet feels like 95 to 100 at home. I make sure to drink a lot of water before and during flights. I had to spend some extra time squatting and bending working on some issues in the PW5 cockpit, but even so, the heat was not unbearable.

The audio vario on the flight computer was acting up. The volume control failed, as it has done before, and when that happens it squawks at full volume. I taped some cardboard over the speaker to make it tolerable. You can't turn it off separately... the computer, vario, and radio are all on one master switch.

The Volkslogger was gone - I assume it was packed up with the Grob for next weekend's campout. So I used my stand-alone GPS unit, and made sure to keep it out of the sun. This was one of the few times I had no problems with it starting up or accidentally shutting off.

Takeoff was the first weird event. I had a couple of equipment problems getting set to take off... just annoying stuff with belts and hoses. I knew that the density altitude would be high, what with the 108F heat. AWOS's altimeter setting and DA were missing, so I just assumed it would be high, and was not surprised that the tow plane consumed most of the runway before lifting off. But I was very surprised to find that the PW5 was still on the ground when the towplane took off! I eventually lifted off, but was way below the towplane. I glanced at the spoiler handle - it was forward. (I didn't tug on it to see if it was locked.) I've had one or two tows where the plane took a very low path, but that was not the case - he seemed to be climbing OK but I wasn't. I felt like I was going slow, likely to stall (unlikely on tow, and the ASI showed 50 to 55 knots), so I was reluctant to nose up too much. I considered aborting, and kept my hand near the release just in case. I think we were up to 700 or 800 feet before I was in "high position" where I belonged. Weird!

I let off a little below 3000' AGL after passing through several spots of 10kt lift. After losing some altitude and then finding a thermal, I gained 1000' and was back up to about 4700' MSL. But I was having to work for it. My plan had been to thermal up high enough to try the southern hills to get me to San Jac, so I headed that way. I found nothing but sink as I headed south, so I stayed over the little canyon where I started. I found ragged little thermals. I used the thermal helper on SeeYou to analyze where the best parts were, but never felt really centered in them.

Weird item #2: I seemed to be flying faster in thermals than I wanted, often creeping up to 55 or 60 kts. Once when flying straight, I went to pull the trim back to help keep me slowed down, and found that I had already trimmed back to #3 (I know it was at 5 or 6 on takeoff).

Weird item #3: I was hearing some wind noise from behind me on the right side, as if the canopy were ajar - and this was over the extra-loud speaker. I made sure no hoses or anything were stuck in the opening.

Weird item #4: I seemed to not be flying as coordinated as usual. When circling to the right in lift, my yaw string was usually off to the right. I was always having to take off some right pressure. That's weird because I had noticed over the last few flights that I was coordinating really well, effortlessly.

I began to think that there was something sticking out or open causing drag and noise (#3), maybe on the right side (#4), or somehow causing me to nose down (#1 and 2).

The sink was outvoting the lift, so I had to get closer and closer to the airport. I could see some other gliders thermaling over the Three Sisters (which is not far from the airport), but even that was too far for me. I spent a bunch of time at about 1200' AGL trying to work some pitiful lift, and eventually had to give up.

Of course, I found zero sink on the downwind leg, keeping me fairly high. My speed kept creeping up to 60-62 knots (no-wind pattern speed is 51), kind of reinforcing my feeling that the glider wanted to fly nose-down. I had a light crosswind on landing, and landed very well... but after just 32 minutes. Aargh! Very frustrating having such a short flight with the mountains beckoning! One other club pilot found very good lift (in the Blanik), and just came back when he ran out of water early. Another in the Blanik got beat down by sink and had an even shorter flight than I did.

I have to admit that I felt kind of "off" for the whole flight. Not enough to cancel takeoff, not enough to head back to the airport voluntarily. Partly the heat, partly the minor equipment problems, partly the annoyingly loud vario (couldn't hear the radio), partly feeling crowded by my stuff in the cockpit...

Back on the ground, I checked the stabilizer and it was latched properly and not at a funny angle. I looked under and around the wing roots, and found no tape gaps or foreign objects that would cause drag or noise. The PW5 had recently been assembled, but another pilot did a complete inspection, and I did a partial and had not noticed any problems.

When I was putting everything away, I noticed that my oxygen hose had pulled out of the socket on the EDS machine. And where it is placed, I can't see it due to the junk pocket. I probably would have noticed had I needed it, because I tested the system on the ground and the fresh, "cool" sensation of each EDS pulse was very noticeable.

  • Is the PW5 just much more affected by high density altitude than I've ever noticed before, and I needed to help it take off?
  • Is there something open or out of alignment, causing drag or nose-down attitude?
  • Was I just "off" due to the heat, and eating lunch right before flying?

Maybe something with the rudder... maybe it's misaligned slightly to the right, accounting for #4, and adding drag? I noticed during Positive Control Check that my partner was applying more pressure than I liked, so maybe I missed that it's staying right... I seemed to have more right rudder than I needed, but then I go by the yaw string action, and I never paid attention to whether my feet were not balanced. I did not notice any undue yaw during takeoff or straight flight or landing.


Sunday, May 11, 2008


Last week I completed a minor milestone: I filled up my first logbook. That's not very important as aviation milestones go, but it did make me think of a few things:

My experience now includes 192 flights, 81:34 hours, 63:46 as Pilot in Command.

In addition to my logbook, I enter my time and flights in an Excel spreadsheet. That makes it a little easier to total things up, check the math, and answer questions like how much time I have in each type of glider. It also handles a quirk of tracking time and flights: once you have your Private certificate, you can log instructional time as both Dual Received and PIC.

Whenever I fill a page of my logbook, I run a photocopy of it. This is really important! I had not thought of it until one of my instructors had several logbooks stolen from a car. The CFI went to a lot of trouble to try to recreate the records, by asking students for copies of their logbooks etc. We put in a lot of work to accomplish our training... to lose the records of it would make it very difficult to apply for certificates and ratings.

My first logbook was the red SSA one, my second is the new blue and white one. One big difference I see is a new column to track Ground Training Received. Also, the front of the new book lists requirements for various tests and ratings.

Saturday, May 03, 2008

Air Show and Air Work

I had a dilemma. I really wanted to go to the Air Fest at March ARB this weekend. I haven't been to a big air show in many years, and the Thunderbirds don't come around very often. But I also wanted to fly, since I've missed the last three weekends and the next three are iffy, all due to other family obligations. Most of the club is away doing winch launching at a dry lake for the weekend, and one of the ships they took is the PW5, so if I was going to fly it would have to be with the help of remaining club members, since the Blanik and Grob take more than one person to move. Fortunately J was planning to go today (giving his wife a ride), so I planned to make flying the priority.

I did go to March Field early, watched about four aerial acts, and quickly walked the static displays, going through a few big aircraft. And I mean BIG... C-5, C-17, and a version of a B737 that is used to train navigators - a flying classroom. Then I headed down to Hemet (about 20 minutes away). I figured if everything went well, I just might make it back up to March for the Thunderbirds at 15:15. But it would be tight: washing, preflighting, his flight, my flight, putting away...

Fortunately an instructor and student were planning to fly the Blanik, so preflight was already done. Then J decided not to take his wife up, for a couple of reasons, and we decided to fly dual. We ate lunch during the student flight, got in a 1 hour and 20 minute soaring flight, and I still made it back to March by 15:20!

Our flight was actually very fun. The weather was favorable for thermals, although the NWS soaring forecast was all wacky. I forecast thermals up to 9,500' with a TI of -4. Thermals were easy to find. They actually topped out at 5,300' (consistently) but lift was strong, up to 6 knots. (Sink was stronger - 8 to 10 kt!) We split duties: I took off and did half the thermals, J did a couple too and did the landing. Flying dual is fun and educational. The copilot can take over some duties (radio, thermal analysis) and helps with the lookout. We learn from each other and make suggestions. (Upside: we split the tow fee. Downside: we can only log half as much PIC time.) I worked on steepening my banks, he worked on speed control in thermals. We were flying the "new" Blanik that the club just acquired - neither of us had flown it before.

I made it back to March nearly in time, but could not get back on base - they closed the gate, since it was nearly the end of the show. But lots of people were watching along the road outside the base, so I found a shady spot and relaxed. The Thunderbirds took off about 30 minutes after the published time, so I did not miss a thing. Six jets in formation make a BIG noise! Of course the show is not confined to the airfield; they go out about 3 miles. So I could see most of the show, and they flew over us a number of times. (I decided not to try to futz with my camera, and just to enjoy the show.)

So my soaring "sandwich" worked out perfectly! I got to see the static displays, a few aerobatic and skydiving acts, got to go soaring, and then watched the Thunderbirds. And I was probably one of the few in the audience that actually flew an aircraft that day! It was a day of contrasts:
  • Visiting some of the largest, most powerful aircraft on earth, and then flying one of the smallest, without any power at all.
  • Flying in a very quiet aircraft, and then hearing some of the noisiest on earth.
  • Watching some of the best pilots do their toughest stuff, and sharing the cockpit with a pilot for a very relaxing flight.
  • Looking up from one airport, and an hour or so later later looking down on another.

A very fun day!