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!!
Thursday, June 28, 2012
Saturday, May 26, 2012
Working more than flying
I had not flown since my great wave flight in March... I've been busy with projects at home and various commitments on the weekends. A lot has happened in the last couple of months. Due to some mid-year leadership changes, I've been appointed President of our soaring club. We've been working on transitioning both of our ships to Crystalaire, which will be our new base of operations for the foreseeable future. With our Blanik trainers grounded until the AD gets resolved, we've been working on some changes in rules and procedures to refocus our club operations around Private Pilots and our glass ships instead of around training.
Today we reassembled our Grob 103 Twin Astir at Crystal and did some maintenance on it. Sometimes the wings go on easily, but today we had a lot of trouble with the second wing. We don't assemble it often enough to have a real "groove" to our process. I took a test flight late in the afternoon in it with another pilot. The weather today was weird: windy out of the west, with some rotor clouds and some cumulus, but no wave clouds. There were few other pilots flying, but those that did reported strong lift and strong sink. It was quite turbulent on tow, and I had trouble with one of the flight controls (which I'm not going to detail), so I was not flying my best. I let off earlier than I planned because we flew through some very strong lift a couple of times. But the lift was hard to work and the wind was strong, and we kept drifting downwind out of it. Having started out low, we did not have much altitude to burn getting back to the lift. After just a few tries I had to enter the pattern. And of course THEN we found strong lift! Although the wind was strong and gusty, it was blowing straight down the runway, so the landing was not difficult (thought I gently bounced it).
After we landed we checked with two other club members who had flown, and our stories all matched: found strong lift on tow, got off tow at about 2,000' AGL, then could not work the lift, and landed after 9 to 12 minutes. That's twice I've done that at Crystal. My new motto is "Won't get fooled again!" No one opted to try a second flight - it just wasn't worth it.
This makes two years in a row that Memorial Day at Crystal was too windy to be fun. Last year was even worse! Maybe as the summer progresses we'll get rid of these Pacific storms and get some normal thermal soaring.
Today we reassembled our Grob 103 Twin Astir at Crystal and did some maintenance on it. Sometimes the wings go on easily, but today we had a lot of trouble with the second wing. We don't assemble it often enough to have a real "groove" to our process. I took a test flight late in the afternoon in it with another pilot. The weather today was weird: windy out of the west, with some rotor clouds and some cumulus, but no wave clouds. There were few other pilots flying, but those that did reported strong lift and strong sink. It was quite turbulent on tow, and I had trouble with one of the flight controls (which I'm not going to detail), so I was not flying my best. I let off earlier than I planned because we flew through some very strong lift a couple of times. But the lift was hard to work and the wind was strong, and we kept drifting downwind out of it. Having started out low, we did not have much altitude to burn getting back to the lift. After just a few tries I had to enter the pattern. And of course THEN we found strong lift! Although the wind was strong and gusty, it was blowing straight down the runway, so the landing was not difficult (thought I gently bounced it).
After we landed we checked with two other club members who had flown, and our stories all matched: found strong lift on tow, got off tow at about 2,000' AGL, then could not work the lift, and landed after 9 to 12 minutes. That's twice I've done that at Crystal. My new motto is "Won't get fooled again!" No one opted to try a second flight - it just wasn't worth it.
This makes two years in a row that Memorial Day at Crystal was too windy to be fun. Last year was even worse! Maybe as the summer progresses we'll get rid of these Pacific storms and get some normal thermal soaring.
Sunday, March 25, 2012
Mountain Climbing in a Greenhouse
We can never quite tell how a day will shape up for soaring. I went to Crystalaire this Saturday not even sure if I would fly, wondering if the weather would turn out like the forecasts, had a long wait for a tow, and ended up having one of my best flights ever!
Winds in front of an approaching Pacific storm were forecast to be from the south. If other conditions are right, this can cause mountain wave lift between the gliderport and the San Gabriel Mountains. The RASPtable forecast for 13:00 at 500 millibars (about 19,000 feet MSL) looked like this. The gliderport is somewhere near the word "Llano". The reddish area would be the strongest lift. But would it really happen?
At the field, lenticular clouds were clearly visible to the east. The senior instructor said the wave was working and had been for several days. The temperature on the ground was much warmer than I expected, and the wind was warm, indicating a foehn effect. I had some tasks to take care of earlier in the day, so I did not get fully ready to fly until about 13:30, by which time there was a line of 5-6 gliders waiting to take off. Then one of the two working towplanes was grounded with an electrical problem, so I didn't actually take off until 14:33. I almost canceled because the southwest wind was 15 knots gusting to 18, which exceeds the PW5's maximum demonstrated crosswind component (a guideline, not a hard limit). But there is a short crosswind runway which aligns very nicely with that wind direction, which would turn a strong crosswind into a great headwind for landing. So up I went.
There was a lot of turbulence on tow, much of which was no doubt wave rotor. I let off tow at 4,100' AGL (7,500' MSL) when we flew into smooth wave lift. I don't remember the exact sequence of climbs and loss of lift (I may update this after I peruse my flight trace), but I easily got up to 13,000 MSL, higher than I had ever been in wave. Most of the time I was heading southwest directly into the wind. The best speed for climbing seemed to be about 48 knots, which is Best L/D speed for the PW5... I expected it to be down around Minimum Sink, so I'll have to think about that. (Comments, anyone?) At times my groundspeed appeared to be nearly zero (though I did not have GS shown on my PDA/GPS... I'll have to add that number to the display) so my airspeed of 48 must have been very close to the wind speed. Look back at the forecast map above: the wind barbs show 45 knots, though that was for 19,000'
Having reached 13,000', my thoughts turned to overflying Mt. Baldy (actually named Mt. San Antonio, about 10,000', and visible as the highest oval in the map above), which has been one of my goals for a while now. That would be challenging, because the wave was 4-5 miles north of the mountains, and I would need extra altitude to fight non-lifting headwinds to get there. The wave lift pretty much paralleled the ridge, so I was able to maintain and even gain as I headed east. By the time I was adjacent to the peak, I was at 16,600'! My previous personal record had been 15,100' over the southern Sierras. Even if I did not make it to Mt. Baldy, this was already a great day!
So I headed toward the peak, but as I mentioned, the winds were strong... my 48kt Best L/D wasn't going to get me there. I had to speed up to 70-75 knots to make any headway, and then of course the glide ratio gets really bad. At times I was seeing 800 to 1000 feet per minute down - not what I needed! By the time I got to the peak - frequently looking over my shoulder at the gliderport getting further away - I was down to 13,000'. SeeYou Mobile was telling me I had plenty of altitude to get back (it's only 14.7 nautical miles), and the look-down angle was good... but I'm really not that comfortable getting far from a landing site. and I have not personally scouted the landout options in this area. And I'm very aware SYM does not know about actual wind conditions, so one always needs to be more conservative than SYM's guidance. If the wind shifted from southwest to west, I would have a big headwind component on the way back. So it did make me nervous. Just as soon as I was over the peak, I turned back to a heading halfway between "direct to Crystal" and "directly back to the wave".
On the way back, I got more of that 1000 fpm sink. By the time I reconnected with the wave, I was down to 9,xxx feet. Back in the wave, I headed west again and by the time I was adjacent to the gliderport I was back to 13,000' again! I had been up for about an hour and a half.
People ask me if it's cold up there. It is and it isn't. I occasionally checked the Outside Air Temperature display, and the lowest I saw at 16,xxx feet, was -10 Celsius, which is +14 Fahrenheit. Yet I was very comfortable in a short-sleeved, lightweight shirt. After about an hour and a half, my feet started to get cold, and there are a few air leaks around the canopy (need to replace some weatherstripping) so there's an occasional draft to the neck. but that's all. The big bubble canopy on the PW5 truly acts as a greenhouse and traps the sunlight, keeping it nice and warm. (Good in the winter, not so good in the summer.) So yes, I went mountain climbing in a greenhouse!
I lost nearly no altitude getting back, and looked directly down on the gliderport from 13,000'. I headed north to lose some altitude, and lost a couple thousand feet or so, but guess what - I contacted the secondary wave (where the senior instructor had reported it hours earlier). Clearly THIS was not the way down. So I headed back south and pulled my spoilers out... and got into some of the worst rotor turbulence I've ever seen, the kind that bounces my head on the canopy and sends radios and stuff flying out of the cabin pockets. I slowed down my airspeed a bit and it was not too bad, and only lasted a couple of minutes. After that I flew with full spoilers, and at times I saw -1250 fpm on the digital display.
As expected, the wind at ground level had not abated, and the tetrahedron showed that the direction had not changed, so I opted to land on the crosswind dirt runway. It's only about 330 feet long before it intersects the dirt approach area of the main runway, and 450 feet to the centerline, but with a strong headwind that should not be a problem. We got lots of practice landing short at Hemet-Ryan! I was quite aware of another glider in the pattern behind me, so I turned off as soon as I could, and was concerned I was in his way as he landed on the main runway, but I was about a hundred feet off the centerline so it was not a problem at all. Total flight time: 2 hours and 2 minutes.
Sorry, no pictures of the beautiful snow on top of Mt. Baldy or the Mountain High ski resort, but I didn't take my camera along this time... and I was kinda busy! I may be able to update this with my flight trace.
Winds in front of an approaching Pacific storm were forecast to be from the south. If other conditions are right, this can cause mountain wave lift between the gliderport and the San Gabriel Mountains. The RASPtable forecast for 13:00 at 500 millibars (about 19,000 feet MSL) looked like this. The gliderport is somewhere near the word "Llano". The reddish area would be the strongest lift. But would it really happen?
At the field, lenticular clouds were clearly visible to the east. The senior instructor said the wave was working and had been for several days. The temperature on the ground was much warmer than I expected, and the wind was warm, indicating a foehn effect. I had some tasks to take care of earlier in the day, so I did not get fully ready to fly until about 13:30, by which time there was a line of 5-6 gliders waiting to take off. Then one of the two working towplanes was grounded with an electrical problem, so I didn't actually take off until 14:33. I almost canceled because the southwest wind was 15 knots gusting to 18, which exceeds the PW5's maximum demonstrated crosswind component (a guideline, not a hard limit). But there is a short crosswind runway which aligns very nicely with that wind direction, which would turn a strong crosswind into a great headwind for landing. So up I went.
There was a lot of turbulence on tow, much of which was no doubt wave rotor. I let off tow at 4,100' AGL (7,500' MSL) when we flew into smooth wave lift. I don't remember the exact sequence of climbs and loss of lift (I may update this after I peruse my flight trace), but I easily got up to 13,000 MSL, higher than I had ever been in wave. Most of the time I was heading southwest directly into the wind. The best speed for climbing seemed to be about 48 knots, which is Best L/D speed for the PW5... I expected it to be down around Minimum Sink, so I'll have to think about that. (Comments, anyone?) At times my groundspeed appeared to be nearly zero (though I did not have GS shown on my PDA/GPS... I'll have to add that number to the display) so my airspeed of 48 must have been very close to the wind speed. Look back at the forecast map above: the wind barbs show 45 knots, though that was for 19,000'
Having reached 13,000', my thoughts turned to overflying Mt. Baldy (actually named Mt. San Antonio, about 10,000', and visible as the highest oval in the map above), which has been one of my goals for a while now. That would be challenging, because the wave was 4-5 miles north of the mountains, and I would need extra altitude to fight non-lifting headwinds to get there. The wave lift pretty much paralleled the ridge, so I was able to maintain and even gain as I headed east. By the time I was adjacent to the peak, I was at 16,600'! My previous personal record had been 15,100' over the southern Sierras. Even if I did not make it to Mt. Baldy, this was already a great day!
So I headed toward the peak, but as I mentioned, the winds were strong... my 48kt Best L/D wasn't going to get me there. I had to speed up to 70-75 knots to make any headway, and then of course the glide ratio gets really bad. At times I was seeing 800 to 1000 feet per minute down - not what I needed! By the time I got to the peak - frequently looking over my shoulder at the gliderport getting further away - I was down to 13,000'. SeeYou Mobile was telling me I had plenty of altitude to get back (it's only 14.7 nautical miles), and the look-down angle was good... but I'm really not that comfortable getting far from a landing site. and I have not personally scouted the landout options in this area. And I'm very aware SYM does not know about actual wind conditions, so one always needs to be more conservative than SYM's guidance. If the wind shifted from southwest to west, I would have a big headwind component on the way back. So it did make me nervous. Just as soon as I was over the peak, I turned back to a heading halfway between "direct to Crystal" and "directly back to the wave".
On the way back, I got more of that 1000 fpm sink. By the time I reconnected with the wave, I was down to 9,xxx feet. Back in the wave, I headed west again and by the time I was adjacent to the gliderport I was back to 13,000' again! I had been up for about an hour and a half.
People ask me if it's cold up there. It is and it isn't. I occasionally checked the Outside Air Temperature display, and the lowest I saw at 16,xxx feet, was -10 Celsius, which is +14 Fahrenheit. Yet I was very comfortable in a short-sleeved, lightweight shirt. After about an hour and a half, my feet started to get cold, and there are a few air leaks around the canopy (need to replace some weatherstripping) so there's an occasional draft to the neck. but that's all. The big bubble canopy on the PW5 truly acts as a greenhouse and traps the sunlight, keeping it nice and warm. (Good in the winter, not so good in the summer.) So yes, I went mountain climbing in a greenhouse!
I lost nearly no altitude getting back, and looked directly down on the gliderport from 13,000'. I headed north to lose some altitude, and lost a couple thousand feet or so, but guess what - I contacted the secondary wave (where the senior instructor had reported it hours earlier). Clearly THIS was not the way down. So I headed back south and pulled my spoilers out... and got into some of the worst rotor turbulence I've ever seen, the kind that bounces my head on the canopy and sends radios and stuff flying out of the cabin pockets. I slowed down my airspeed a bit and it was not too bad, and only lasted a couple of minutes. After that I flew with full spoilers, and at times I saw -1250 fpm on the digital display.
As expected, the wind at ground level had not abated, and the tetrahedron showed that the direction had not changed, so I opted to land on the crosswind dirt runway. It's only about 330 feet long before it intersects the dirt approach area of the main runway, and 450 feet to the centerline, but with a strong headwind that should not be a problem. We got lots of practice landing short at Hemet-Ryan! I was quite aware of another glider in the pattern behind me, so I turned off as soon as I could, and was concerned I was in his way as he landed on the main runway, but I was about a hundred feet off the centerline so it was not a problem at all. Total flight time: 2 hours and 2 minutes.
Sorry, no pictures of the beautiful snow on top of Mt. Baldy or the Mountain High ski resort, but I didn't take my camera along this time... and I was kinda busy! I may be able to update this with my flight trace.
Monday, February 27, 2012
Update on Blanik L13 situation
We are still waiting for the FAA to complete their assessment of a Supplemental Type Certificate that has been submitted to deal with the Blanik L13 airworthiness issue. It's been in process since about May 2011.
The parts kit alone would cost about $8,700.
- The FAA's statement as of early February
- The STC applicant's description of the inspection and repair process
The parts kit alone would cost about $8,700.
Sunday, February 19, 2012
Seagull Soaring Index
I have a 2-meter "foamie" radio-controlled glider that I occasionally get to fly, mostly ridge soaring along ocean cliffs. It's relatively heavy, so it takes a pretty strong wind to keep it aloft, unlike the little Zagis and molded foam warbirds that have been developed in recent years.
On some long trips to the dunes at Pismo Beach, CA I invented my "Seagull Soaring Index". I watch the seagulls that are ridge soaring, and mentally count the longest intervals between episodes of flapping. If they can soar for 6 seconds at a time or longer, the wind is strong enough to launch my Highlander. Any less, and I will be trekking down the hill to retrieve it.
Smaller ships would probably fly on a SSI of two or three. I've thought of getting a wing or smaller glider, but since I really don't get to fly R/C all that often (I'd rather fly "full-scale") it's not worth the cost.
What weather-related "rules of thumb" do you use to help decide whether today (or tomorrow) will be a good soaring day?
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