Friday, March 18, 2011
Progress Toward Hemet-Ryan
This week the Riverside County Board of Supervisors, on the advice of their counsel, declined to appeal the ruling of the FAA to allow gliders to operate at Hemet-Ryan Airport. One more obstacle out of the way! It will take a few months to work out arrangements (leasing space, filing operating plans, etc.). But it looks like it will happen!
Saturday, March 12, 2011
Sunglasses for Soaring
A reader asked me about sunglasses. Here's what I know and what I think.
- Aviator sunglasses are designed to prevent light from coming from a wide range of angles, so they all tend to have a large teardrop shape. They don't change much to follow fashion. I happen to like mine, so I wear them for general use as well, not just for flying. A long time ago, I used to get headaches from bright sunlight, so I tend to wear sunglasses most of the time I'm outdoors or driving.
- Polarized sunglasses generally should NOT be used for aviation. Two reasons - one pretty obvious, one more subtle:
Cockpit glass and canopy (or plastics) may have some unintentional polarization, and when combined with polarized sunglasses can show dark spots, distracting color patterns, and even large dark areas which can greatly interfere with vision. Some instrument glass windows, devices such as handheld GPS units and PDA's, and digital watches can also be partly polarized and difficult to read. We need to reduce problems in the cockpit, not create them.
Polarized sunglasses are designed to cut glare. But sometimes a little glare is a good thing! When we're flying, we're always looking for other air traffic, sometimes at great distances. Depending on light conditions, sometimes a "glint" off a distant aircraft's canopy is all you ever get to see - but that may be enough to catch your eye and distinguish the aircraft from a plain background or from ground clutter. Polarized sunglasses tend to filter out that "glint" and make it harder to see small, distant aircraft. Glare from our own aircraft tends to be not so much of a problem, due to the design and colors of dashboards, cowlings, etc., so I've never felt that losing the polarization caused me any local problems. - I started out using American Optical's FG-58 sunglasses. They were advertised as kind of the "standard" aviator sunglasses used by the military. They were OK, but due to the straight and kind of heavy design of the temple, I found them a little uncomfortable. They're pretty rugged. Although I've switched away from them, I still keep them in my gear bag as a backup, or in case I ever have a passenger who needs sunglasses.
- When I started using a PDA for soaring navigation, I found the AO's to be too dark. I couldn't see my iPAQ's screen. I switched to "gradient" sunglasses in which the lower part is not as dark as the upper part. That way when I glance down I can see the PDA screen, but when I'm looking out the cockpit I get more protection.
All that could apply to any kind of aviation. But for soaring, there's one other feature that I learned to love. Yellow lenses help you see cloud structure better than other colors. It sounds like a trick, but seeing is believing. There's something about the colors of light that water transmits, and the fact that yellow lenses filter out more blue light, that enhances the contrast of clouds, especially the thin wispy parts.
When we're soaring on a day when cumulus clouds exist, we look for clouds that are just starting to form - they have the strongest lift. If you look at the bottom of a "young" CU, it may look flat or slightly concave. That's where the rising moist air cools to the dew point and the cloud forms. But look carefully below the bottom of the cloud. Sometimes you can see that it is not a definite line, you can see wispy trails leading up to the base. You're actually seeing the water vapor starting to condense, and you'll see it more in some places under the cloud than others. Those are the areas of strongest lift. Try this (even from the ground) with and without yellow sunglasses. Huge difference! With lenses of other colors you may not see those wisps at all and with the yellow lenses they pop out at you. Sometimes you can spot the wisps a few minutes before you can see the CU at all - and when you're hunting lift, sometimes that makes all the difference.
So I'm now using Serengeti Aviators Drivers Gradient glasses. I like them a lot. Only two things I would improve about them:
- The lenses are not as hard as some other sunglasses. I scratched my first pair after a year or two, right in front of my pupil. I got another pair and am much more careful with them. I always keep them in a semi-rigid case with a soft lining.
- The temples are a pretty thin wire. They're strong, that's not a problem. But I have a radio earpiece that I clip on when flying some gliders, and the temple is so narrow the clip slides around a bit. Not a big problem - I much prefer the smaller and lighter temple compared to the AO's.
Thursday, February 17, 2011
FAA rules in favor of soaring at Hemet-Ryan Airport
We won! After a year and a half, the FAA has ruled that the County of Riverside violated Federal law when it closed the glider runway and prohibited gliders from taking off on the main runway at Hemet-Ryan Airport.
Since they have accepted Federal grant money in the past, they must not discriminate against any type of aviation activity unless there's a safety issue. FAA ruled that gliders can operate safely, recommended some procedures, and ordered two-minute windows for winch launching, which we did not even ask for!
The County must submit a plan, negotiate in good faith, and consult with FAA, or they will be denied future Federal funding. Unfortunately the FAA ruled that the County does not have to pay costs or damages incurred by the clubs and private owners that were displaced.
Our club, the Orange County Soaring Association, filed the complaint. We've been fine-tuning our winch operations at several other locations and hope to return soaring to Hemet-Ryan in the near future. First we have to see how the County reacts, file an operations plan, etc. Stay tuned!
More information:
Since they have accepted Federal grant money in the past, they must not discriminate against any type of aviation activity unless there's a safety issue. FAA ruled that gliders can operate safely, recommended some procedures, and ordered two-minute windows for winch launching, which we did not even ask for!
The County must submit a plan, negotiate in good faith, and consult with FAA, or they will be denied future Federal funding. Unfortunately the FAA ruled that the County does not have to pay costs or damages incurred by the clubs and private owners that were displaced.
Our club, the Orange County Soaring Association, filed the complaint. We've been fine-tuning our winch operations at several other locations and hope to return soaring to Hemet-Ryan in the near future. First we have to see how the County reacts, file an operations plan, etc. Stay tuned!
More information:
Monday, February 07, 2011
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!
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!
Friday, February 04, 2011
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.
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