Winch launch in the PW5

This weekend we again conducted winch launches at Crystalaire gliderport. The weather was nice - low 70's all day, enough to create a little "zero sink" lift, but not enough wind to help with the launches. (Sorry to any eastern readers... not trying to rub it in!)

You might recall that the other times I tried winch launching in the PW5 (almost a year ago) I had an aborted takeoff and then a winch failure, so I've never really had a good launch. Since I had four good launches in the Grob 103 two weeks ago, I was eager to try the PW5 again.

The CG hook on the PW5 is really low to the ground, well below the actual center of gravity, so there's a significant rotational moment which raises the nose. On a glider with a tailwheel on the ground, that's not a problem. But the PW5 rests on its nosewheel, with its tail up in the air, and that rotation caused the tail to strike the ground as soon as the winch started pulling. Our winch has been improved over the last few months, so it's even stronger than before and could really slam the tailboom, so we decide to start with the tail on the ground. The way to do that is to have a person hold down the stabilizer until the glider starts its ground roll. That means that the nose is pitched up at a rather unusual attitude. What does that mean for the elevator position - will I need to hold the nose up, or push it down to fly level? What about the trim setting, which for my weight is supposed to be fairly far forward? These are all things I'll have to work out in the first... um... 0.7 seconds of the takeoff roll.

The first launch starts out smoothly enough. The nose angle seems good, and there's no tendency to PIO like my first time. But I'm keeping an eye on the line and the parachute, and I'm flying faster than it again. Before I am high enough to rotate into the climb, the 'chute disappears below me on the left side, so I have to release and land straight ahead (which goes perfectly well).

The ground crew agrees it was straight and smooth and good, but they say there was a gust of tailwind just as I took off. That probably helped the glider accelerate and helped the parachute inflate, which contributed to outrunning the line. And our experience has shown that once the 'chute inflates, the glider always passes it by. What to do? We decide that the winch driver needs to not use full speed with the PW5, so it won't accelerate so fast, and will keep some load on the line in the early part of the flight. The PW5 empty is 400 pounds lighter than the Grob 103, and it only carries one person, so it's nearly 600 pounds lighter all told. It just doesn't need full power like the big Grob 103 does. We also think that keeping the nose up slightly will present some drag, which will help keep the line taut.

Launch #2 goes just fine. The line stays tight, I can gain a little altitude, and then rotate into the climb. The speed in the climb stabilizes at 60 knots, right where I want it to be (the maximum allowed is 65). It climbs just fine. Finally the glider starts to level out, and I can look down and see that I'm nearly over the western airport fence. So I nose over to relieve the line tension, and release at about 1300 feet AGL. If there had been a headwind it would have been higher.

We've designated an area to the left of the runway where we can look for lift without interfering with either the right (glider) landing pattern or the left (towplane) pattern. I look around there and find a little zero sink, but nothing strong enough to lift me up more than 150 feet or so. The thermal forecast for today did look like there could be lift - no inversion to stop it - but it was not to be. With only 450 feet above pattern altitude to play with, I couldn't go very far, and soon enough I was calling my pattern entry. I had a good landing and rolled off into the parking area.

Later three other pilots launched in the PW5. Two of them had done it before, and one had not. One of them thought that his weight would be enough to counteract the rotational moment, so he opted to start with the tail up. Wrong! Slam! After that one, we all agreed that we need to always hold the tail down. I think everyone's release altitude was about 1300 to 1500 feet.

Here's a video of one of the other pilots launching. From the time you hear the line boss say "Launch, launch, launch" until the glider is in the air, it's about 2.5 to three seconds! This one is noisy, but that's just normal bouncing noise since we're launching on dirt with some rocks. The tail-slam was even louder!

Logbook in Excel

I've copied my flights from my paper logbook into an Excel spreadsheet for several years. There are several advantages to having my logbook in electronic format:

• Easy to search for a particular flight
• Does the time arithmetic to carry forward from page to page
• Can print a copy for safekeeping
• Can use Excel analysis tools to count up flights and time in different ways. Like: "How many times have I flown model X vs. model Y?" I used it a lot when writing my last post, Review of 2010.

I've added several Pivot Tables to the spreadsheet recently to make that analysis really easy. I thought others might like to give it a try, so I've posted it for download here. Instructions are provided on the second tab. It has a few glider-specific fields, but it could easily be adapted for power pilots' use as well. Give it a try and let me know what you think.

Review of 2010

2010 had its ups and downs. I completed my Silver badge, but we saw our training fleet grounded and our club struggled to find a new operating model. Here are some highlights.

I had a total of 28 flights, 5 fewer than in 2009, but 17 hours, 4 more than in 2009:

• Nine flights with instructors
• Seven flights with other Private pilots
• No flights with student pilots
• Two passenger flights
• That leaves 10 solo flights
  
• No cross-country flights
• Four winch launches

I got around some:

• Four flights at 29 Palms
  
• Ten flights at Crystalaire
• Six flights at Lake Elsinore
• Eight flights at Tehachapi
  

I worked toward my Commercial and Instructor ratings early and late in the year:

• Two flights at Lake Elsinore in the Blanik L13
  
• Seven flights at Crystalaire in the Grob 103
  

Along the way, I did have a major accomplishment and some fun flights:

• I had my longest flight ever, 5 hours and 11 minutes, to complete my Silver badge. First time in my life I've had someone douse me with champagne!
• First really successful flights exploiting shear line lift at Tehachapi
  
• First flights at Crystalaire.
  
• Learned a bit about flying in wave over the mountains near Crystal. Lots more to learn!
• A really successful passenger flight in which we were able to thermal with gentle turns
  

And some bad news:

• All Blanik L13's worldwide were grounded after an accident in Europe. They're grounded until a testing plan is developed and approved. (I did get to learn some interesting things about aircraft safety and documentation procedure as I helped prepare paperwork related to our club Blaniks.)
  
• The FAA never ruled on our complaint about Hemet-Ryan airport, so we lost a whole year in that battle. The ruling is due "any day now".
  
• My plans to take my Commercial and Instructor Practical Tests did not progress much. I was not satisfied with the prospects of taking the tests at Lake Elsinore, and we lost the use of the Blaniks. Late in the year we placed our Grob at Crystal, and I resumed training late in December.
  

So... another mixed year. I continued to fly as much as possible, but there were three months I did not fly at all, the most I've ever sat out. We'll see what happens in 2011 - I'm hoping to do some cross-country out of Crystal, and I'm hoping to fly at some other gliderports as I take a family trip to Kansas in the summertime. And I have several friends and relatives who say they want to fly this year.

Winch Launching the Grob 103 at Crystalaire

Over the last few years our club has developed our winch launching program by refurbishing our winch, by training a number of pilots, and by testing it at several different locations. We have launched the Blanik L13's many times, and the PW5 single-seater several times. Our Grob 103 Twin Astir did not have a center-of-gravity hook, and it was considered pretty heavy and not really a training ship, so we had never winch launched it. The grounding of the Blanik L13 fleet put us on hold for a while, but the club refused to give up. We found out that there is an approved CG hook add-on for our ship, which could be purchased and installed for less than $1,000. It was completed on our ship in mid-January. And some of our mechanically adept members have made improvements to the winch which have increased its power and reliability. The operators of Crystalaire have been open to having us conduct winch launches there. The runway plus dirt extensions add up to about 4500 feet which is plenty long for winch launching. So finally it has all come together. The question remained: how well would the winch launch the Twin Astir?

So the club organized a "Winch Weekend" at Crystal. I wasn't able to make it Saturday, which was just as well because the winch engine broke down after just two launches. But the crew was able to get the part and fix it early Sunday morning, so we were back in business.

Winds were good, probably 8-10 knot and at just a slight angle to the runway. Our instructor took a solo flight, then did some flights with one of the senior instructors from Crystal. The verdict was in: the combo of our winch and our Grob 103 Twin Astir works great! It accelerates really well, climbs straight and smooth. The winch has plenty of power, and its shifting of gears is not a problem. Launches were anywhere from 1300' to 1600' in the early flights. We also launched one of Crystal's gliders which I think is about 100 pounds heavier, with a greater wingspan and much better performance, and it got up to 1800'. Wow!

I was next up for a couple of launches with our instructor. If you've been following my blog you'll recall that I have had quite a few winch launches in Blanik L13, and several abortive launches in the PW5. The first few times I winch launched in the Blanik L13 it really got my attention: 0 to 55 in about three seconds, really startling the first time. I expected the heavier G103 would accelerate a little more slowly. Quite the opposite: with our beefed-up winch, the acceleration is even faster. The first one this time actually gave me a bit of a "head rush". I estimate we're now going to 50 or 55 in less than two seconds. I did some back-of-the-envelope calculations, and I think that's between 2.5G and 3G or more of acceleration. To put this in perspective, some of you may be familiar with thrill rides that use linear induction motors to accelerate ride vehicles. The one I'm familiar with is California Screamin' at Disney's California Adventure park. It goes from 0 to 55 in four to five seconds. I think the acceleration of our winch launch is nearly twice that. (I didn't notice the "head rush" effect on later launches.)

Once we were moving, the G103 seemed very smooth and eager to climb. I focused mostly on staying wings-level in the climb. The best climb rate requires having the stick all the way back or nearly so. There's sometimes just a little "porpoising" as the line gets little amounts of slack or as the winch shifts gears, but it's not very noticeable. My first launch was to 1300' AGL. The first thing I noticed after getting off the rope was that it's a little difficult to get one's bearings. During the climb, you can hardly see the ground due to the steep angle. Getting off the line nearly over the winch, the airport is behind and below, and you can't see it until you turn. All you can see is the nearly featureless desert. Once we completed our turn first turn I could see the airport and get reoriented.

On the second launch, we got to 1500' AGL but then the weak link broke. We don't think we pulled on it too hard, because that launch was about the same as the previous 5 or so of the day. It may be that the link was getting weaker with age and use, and it was just its time to break.

My first landing was not as close to the beginning of the dirt touchdown area as my instructor would have liked. Probably I was aiming a little further out because of the proximity of some wires on that end of the runway. The next time I brought it in steeper, established my aiming point closer in, and had a good landing (e.g. we didn't have to pull the glider back quite so far).

My third flight right after that was solo, and the launch went quite normally. I got up to 1400' AGL before releasing. Shortly after turning north I found lift, probably thermal. It was pretty big, and was anywhere from 300 fpm to 700 fpm and fairly consistent. I worked it for just a short while and probably could have soared away. (I spotted a hawk doing some aerobatics below me.) But this was not a day for soaring, since we were trying to get several people experienced with winch launching the Grob. So I came back after just 10 minutes. But I'm convinced that when the weather heats up we'll be able to hook thermals and get away.

A number of other people had instructional launches and short rides. I prepped the PW5 for flight, but it was getting late and we had other priorities, so I'll launch it another day. As it turns out, I flew the G103 once more late in the afternoon, the last flight of the day. One of the Crystal staff wanted to go for a ride (has flown in gliders many times but not had a winch launch). So off we went again. The initial acceleration was a little bumpy, which was new. Later we figured out that as we rotated the ship to line it up for launch, we dug the main wheel into a bit of a hole in the sandy soil. Next time we'll know to push it forward a bit so that it doesn't have the resistance of having to pull out of a hole. Not that it's a problem for the winch - plenty of power there! But it makes the initial roll start with a bump, which you don't need when you're getting to 55 in 2 seconds. Anyway, we got up to 1400' and released. We found a little sustaining lift but it didn't keep us up very long - by this time the sun was getting fairly low in the sky so the thermal was weaker. She had a great time, and we came back after just about 7 minutes. This time I intentionally landed long onto the paved runway (really smoothly, if I may say so), and rolled all the way to the east end of the airport, stopping perfectly in front of our tie-down spot.

I think we had a total of 14 winch launches that day. A good beginning to what we hope will be a new standard operating procedure for the club at this location.

Discontinuing work on Commercial and Instructor

Followers of this blog will recall that I was days away from taking my Commercial and Instructor practical tests back in September 2009, when gliding at Hemet-Ryan airport was abruptly shut down. I had completed all three written tests, and completed all my flight training requirement. Since then it has been difficult to work out a combination of aircraft, gliderport, instructor, and examiner that would enable me to finish the practical tests at an acceptable cost.

Recently I had resolved those logistics, or so I thought. I had resumed working toward completing my Commercial certificate before my written test expires at the end of January, and my Instructor certificate by the middle of March. I have been flying with an instructor in the club Grob 103 at Crystal, revisiting the maneuvers for the flight test and getting current on the required instructional flights. I have come to realize that I would not be sufficiently prepared for either the oral or flight portions of the Commercial test by the end of January. In addition, trying to balance this work with a number of other family commitments and projects was causing me some problems. I simply needed more study time and more practice than I would be able to accomplish before the deadline. I could retake the written test and continue on, but I have decided it is not going to work out at this time. There are several factors leading to this decision:

• Proficiency in the Grob. I was well prepared for this test a year and a half ago in the Blanik L13 (before the Hemet crisis). But I have three times as much experience in the L13, and the Grob 103 Twin Astir (at least our unit) is more difficult to fly precisely from the rear seat. Some of the things that I need to demonstrate for the test are things I have not used recently in recreational and cross-country flying, so I’m out of practice on those maneuvers. I could get there, but not quickly enough.

• Preparation for oral knowledge testing. I was prepared for this part a year and a half ago, but that knowledge (airspace requirements, regulations etc.) fades if it’s not refreshed. Since the time the OCSA Grob became available at Crystal, and I located an acceptable examiner, I have not had time for refresher study due to a family situation that is requiring much more of my time over the last few months.

• Cost. When I started on these ratings three years ago, I was able to work with the OCSA volunteer instructors (whom I greatly appreciate!), the tow fees were significantly less at Hemet, and the drive and gas prices were much less. (For example, Crystal does not offer a break on pattern tows.) I understand why Crystal’s tow fees are higher – better facilities, great services, and fuel has gone up – but I can’t afford $450 to $650 in tow and instructional fees and other expenses every flying day – and I would need many more flying days to go on to the Instructor rating. Getting the proficiency I need in the current situation will be too expensive. It could easily cost another $3,000 to $5,000 to complete the Instructor test. Maybe I’ll be able to resume in a lower-cost environment in the future… Lake Elsinore Soaring Club’s tow and instructor fees are lower, but there are some other issues in taking practical tests at that location that I will not comment on here.

• Purpose. When I started on this three years ago, I planned to become a CFI in the club environment, and “give back” to OCSA and soaring. I realize that each certificate is a “license to learn”, and I was expecting to work under the guidance of our club CFIs, and work with our constant flow of primary students as I built up my knowledge and skills. Now that the OCSA teaching environment has changed due to the Hemet and Blanik L13 situations, I don’t know what I would even do with my CFI rating. I don’t envision working as a paid instructor on Saturdays at Crystal or anywhere else. I don’t especially want to teach in 2-33’s for Lake Elsinore Soaring Club. A CFI needs to train and solo and recommend a minimum number of students to stay current – and I don’t see that situation in my future anymore.

So until some of these factors change, I’ll put my Commercial and Instructor ratings on hold, and re-take my knowledge tests later if necessary. This is a difficult decision, since I have been working on this for three years. I greatly appreciate the training and guidance I have received from my instructors, and the support of my OCSA friends. I’ll continue to fly the Grob and PW5 for fun and wave experience at Crystal and elsewhere with OCSA, and look forward to some cross-country flights this summer.