Sunday, October 4, 2015

Saturday October 3, 2015

Visibility: unlimited
Wind: 5-10 kts out of the SE early in the day, then 15 kts.,  gusting to 20 kts. plus,  out of the West and SW later in the afternoon.
Altitudes: 9000 ft. MSL by Mario Pauda in the 1-26 from a 2000ft tow.
Time Aloft: 3.0 hrs by Mario Pauda in the 1-26
Max Lift: 8 kts steady in the convergence, touching 9 kts briefly at times.
Temperature: 91deg. F. at about 3:30 PDT
Comment: The RASP was spot on in predicting  a good convergence in the later afternoon right over Avenal.  
Tow pilot: Jim Rickey

              Mark Neal and Alex at about 7500 MSL over the Kettleman Hills. 

We had a very good day of flying at Avenal today. A strong convergence,  predicted very accurately the night before by the RASP, developed early over the Diablos. In the later afternoon, it moved right over the airport and then over the  Kettleman Hills just to the East of the airport.  The altitudes obtained, winds, clouds,  along with the timing of the events,  were all predicted by the RASP with uncanny accuracy today.


Glider pilots showing up were Sergio Grejada, Mark Neal, Alex Caldwell, Mike Paoli, Joe Anastasio, and Richard Walker as well as Jim Rickey who performed as our tow pilot. I believe I also saw Ed Mandibles, although I didn't see his cool Mooney Mite anywhere, so he must have driven out.  I think Ed may have been working  on the 2-33.  


Early in the day, the wind was out of the SE,  but very light,  and we made a couple of tows downwind off runway 31.  But a little  later in the morning, the wind increased to about 5-10 kts from the SE, so we moved operations to runway 13. Late in the day, around 3:30 or so, when the convergence arrived over the airport,  and as it moved further east over the Kettleman Hills, the wind filled in strongly behind the convergence and shifted fairly abruptly to the West and SW and came up to a steady 17mph with gusts over  20mph. We started getting some blowing dust in localized areas in the valley, along with some very large dust devils along the convergence line.  We also saw a few very whispy,  transitory cumulus clouds along the convergence line parelleling the Kettleman Hills and extending up towards the San Benitos north of Coalinga. See pictures below.



Sergio and Alex flew one flight in the early morning. Sergio is doing the take-offs and tows by himself and boxed the wake on his own today.  He found it much easier to practice this in the smoother morning air.  He's got his student license now,  and is studying for the pre-solo written test. Next,  he'll be continuing to sharpen up his pattern and landing judgement,  and starting practice for various emergency procedures.


 Mark Neal and Alex had a great flight in the Orange Crush for 1.5 hrs plus. We got to 7600 MSL in the convergence over the Kettleman Hills. We then descended to about 2000 MSL, over the airport after unsuccessfully trying for a big dust devil over the power lines.   Just as we were starting our landing checklist, we encountered lift that allowed us to get back in the convergence and we climbed again to the same altitude, with lift at times steady at 8 kts, and briefly even seeing 9 kts on the vario.

                                                A steady 8 kt. climb

 One of the large dust devils forming along the convergence line.                                                          

Mario Pauda in the 1-26,  working the convergence over the Kettleman Hills. He eventually climbed to 9000 ft. MSL!

Pilot Reports:

Mario's Flight:

Flying with the Birds

(Alex asked those of us who flew on Saturday Oct 3 to write a short summary of the afternoon flights, with attention to how we found the forecasted convergence, how we are doing on our training. So here it is, hoping some of us newer glider pilots may benefit from it.)

I was in the 1-26 in a 50 degree right-hand turn, climbing with the vertical velocity indicator (VVI) pegged on the positive side, sharing the thermal with three black birds (most likely common vultures, but as close as I was to them, they looked as big as condors to me). I was over the Kettleman Hills, just south of Avenal, where the RASP predicted the convergence would be around 2 PM. The forecast was for the convergence to move further east in the afternoon, as the winds out of the west became stronger.

As for staying in the convergence band, I used the “drunk flying” technique that our own Morgan describes in his presentation, Convergence Flying in Central California: fly in the general direction you expect the convergence to extend, then, when you hit the wall of sinking air at the edge of the convergence zone, make a slight course correction to stay within the band of lift, just like a drunk B-52 pilot trying to stay on his feet. There were no clouds to mark the general lay of the convergence, although I did follow the three black birds as they played in the lift, porpoising as I went from thermal to thermal (a first for me).

And what beautiful thermals they were. The 1-26 is so light, and flies so slowly, that cranking it around at 50 degrees of bank in the core of the thermal was a blast (note to Harold, my instructor: my turns to the right were coordinated!). I saw Alex and Mark thermalling in the 2-33 just a little north of my position, still over the Kettleman Hills. I went to join them. They were above me, circling in nice lazy circles. We had a gaggle of five: two gliders and the three black birds. I reached 9,000 feet MSL in this thermal. From this lofty height, I could see the intersection of roads 41 and 46 south-southwest of Avenal. I headed in that direction, flying out of the Kettlemans and out of the convergence…and into the sink. The sink was too much for the 1-26 (not to mention for the pilot of the 1-26). I abandoned that goal, and instead, went to look for thermals in the foothills east of Black Mountain (I was nowhere near Black Mountain itself). No luck. So I turned back to the field, now flying with the wind.

I was nearing three hours of flying time. I was thinking it would be nice to log three hours. So I kept going past the field into the Kettlemans, pushed by the westerly wind, hoping the convergence was still there. It was, but it, too, had been pushed by the wind, and now it was closer to the east edge of the hills (and further away from the field). I was down to 4,000 feet; I found a weak thermal. With each turn, I climbed just a few feet, but got pushed east one hell-of-a-lot. Time to go home. With the nose down, flying at 65 to 70 mph with caution and avoiding sudden control inputs, I flew directly to the field, reaching it at about 1200 AGL. I flew a tight pattern because Alex and Mark arrived in the 2-33 at an extended downwind just as I crossed the field. Once again, they were above me. The wind sock was “stuck out” horizontally, at almost 90 degrees to the runway. I practiced my crosswind landings, did not ground loop the glider. After climbing out of the glider, I had the opportunity to  watch Alex land the 2-33 in the crosswind—very nice, Alex.

It’s good to be back!

Thanks to everyone who helped me put the glider away. And thanks to Jim for towing me to lift!

Total flight time: 3 hours
Max altitude: 9000 ft MSL
Release altitude: 2000 ft AGL

PS don’t forget to wish Sergio Grejada a happy 21st birthday (Oct 8)
Editor's Note: I think the birds were Ravens. We also saw them doing rolls and split S's as they flew with us.

      Mario filling out log book after a good flight!

Mike Paoli's report:

Saturday, I made my third flight in the Libelle. Jim Rickey gave me a great tow to near the crop circle, where I climbed to 6,000 ft. Over the next hour, I was maintained from 3,500 to 5,000 ft. along the base of the Temblors, near the power lines; along the west side of the Kettlemen Hills, near Avenal; and in the area from the gliderport to the prison. I could have stayed up longer but I was becoming increasingly concerned about the surface winds.
The wind at noon was from the SE at 2 mph, gusting to 9 mph. By 5:00 PM, it was from the SSW at 15 mph gusting to 27 mph. At times, the windsock would blow in one direction while at the same time dust near red barn was blowing in another.
The wind blew directly across the runway and into our trailers while we disassembled our gliders. Thanks to great teamwork, we completed the process without mishap. I will bring a shovel next week to clean out my trailer and cockpit.
Thanks to all for the assembly and disassembly help and the encouragement throughout the day.

Joe Anastasio's Flight:

The RASP promised a strong convergence, passing over the field at about 1600.  I launched at 1500 and found good lift to 4000' west of the airfield.  Heading for the hills I found sink, some zero sink, but the lift was to the east.  The convergence moved through as scheduled, but I fell out of it as it swept over the Kettleman hills, and did not have the altitude and stones to push to the east, especially as a strong wind started blowing in from the west.

I got to practice a crosswind landing,  By 1630 the winds were gusting from the west, raising a lot of dust.

We all had to pitch in to get the gliders put away, as we had quite a dust storm to end the day.

A couple of videos by Mark Neal from the Orange Crush while flying with Mario in the 1-26: 





Amateur analysis of weather predictions for the day.

One thing to remember is,  while the RASP and some other self briefing  tools are very helpful to us soaring pilots, they do not by themselves constitute an FAA recognized preflight briefing. They do not include things like NOTAMS, TFRS, SIGMETS, AIRMETS, METARS, Terminal forecasts, Area Forecasts, Winds Aloft forecasts  and other important things you get with an FAA recognized briefing. 

The synoptic situation i.e. the "big picture" was interesting, with a closed low digging down into California from the Pacific NW. as shown by this NOAA GFS (Global Forecasting System)  computer model forecast from Friday evening  showing the 500mb "Heights" and "Vorticity".  500mb is a pressure level  corresponding to about 18,000ft. and generally  gives you the "steering winds" which parallel the lines of equal "heights", or pressures,  and give you a good idea of the large scale motions and pressure patterns in the atmosphere.  This forecast was generated Friday at 5:00p.m. PDT for Sun 10/4 at 0000Z which actually  5:00pm PDT Saturday, about when we were getting the best lift of the day. This time of year we can get some good soaring days as we start to get winter weather patterns, with low pressure systems moving in periodically.   The days are still long enough to allow heating of the still dry  ground. This  tends to  generate good thermals when combined with  these low pressure systems bringing  in cooler air aloft from the north.  Often the low pressure  systems do not have enough moisture and the atmosphere is still warm enough to keep the relative humidity low.  Extensive cloud cover and precipitation often does not develop until later in the season, leading to good local soaring conditions for a number of weeks longer.  This time of year, you need to pay closer attention to the bigger synoptic scale picture and be more selective in choosing the best days to fly,  if you want to get in the best soaring.


This is a "Water Vapor" animation from the compostite GOES  West and East  satellites shows what actually happened from about 7:00a.m. to 4:30p.m. PDT on  Saturday. You can see the same general pressure patterns,  with the closed low digging down into Northern California.  The Water Vapor Satellite imagery shows pretty much what the GFS computer model was predicting the evening before, perhaps the closed low is very slightly further to the East than the GFS predicted. Of course this Water Vapor animation was only available AFTER the events actually took place, whereas the GFS forecast was from the day before. Sometimes you can look at the Water Vapor or other Satellite  animations up to the current time, and sort of "project" them  forward a certain number of hours in your mind. This actually often works fairly well in predicting arrival of fronts or that maybe things will be rather stationary for a while,  as long as it's just a few hours ahead that you're trying to predict.

Here is what the RASP model was saying by  late Friday Evening.  The next 3 images are for the "BL max Up/Down" or "Convergence" from 1300, 1500 and 1700 PDT. The convergence was over the Diablos at 1300 PDT, but the RASP  was predicting that it would move to the East and be over the Kettleman Hills by 1700 PDT

The predicted "BL top" from the next 3 RASP blipmaps was about 9000 MSL at 1700 PDT just over the Kettleman Hills. The BL top is the highest thermals should go. Often you can't quite get that high, especially in a low performance glider, but Mario Pauda climbed to 9000 MSL in the predicted location of the convergence and best BL Top RASP forecast at that time. 

The surface winds changed dramatically as the convergence arrived and moved over the airport to the East. This was predicted quite well by the RASP as well. You can see the very light winds still at 1300 PDT, shifting by 1700 PDT to the West and SW and increasing in strength on the next 3 blipmaps. You can also see that the winds on the East side of the convergence are still out of the SE and fairly light. Also note the very sharp change in wind direction and strength along the convergence line just to the East of Avenal roughly paralleling the Kettelman Hills and I-5.

The RASP also predicts cumulus clouds. It predicted there would be very few or no cumulus most of the day, even though the convergence lift was still  forecast to be quite good along the Diablos early in the day to the West,  and later in the day as the convergence moved East,  over the Kettleman Hills. It showed on the 1700 PDT "Cu cloudbase where Cu Potential > 0" forecast that there would be a few cumulus with bases at  8500 MSL over the Kettleman Hills in a line towards Coalinga and the San Benito Mts. North of there. We did see some individual persistent cumulus clouds over the San Benitos with nice flat bottoms. We saw some transient more whispy ones along the predicted convergence line over the Kettleman Hills. The cloud bases were estimated to be pretty close to what the RASP predicted. 



One of the whispy cu's the RASP predicted on the convergence line.

 The RASP produces "sounding" forecasts that are plots of the temperatures aloft, dew points aloft, wind strength and direction aloft. They are plotted on a logarithmic graph called a SKEW-T/LOG-P format. These are very useful when you get used to working with them. You can glean much information about conditions over a given point on the ground. They also show high level clouds such as cirrus that do not show up on any of the blipmaps. Another thing they show that RASP blipmaps do not, is the altitude and thickness of multiple cloud layers,  and whether there will be any preciptiation. They are not as good as blipmaps for looking for convergence lines and mountain waves.  However,  you can see the effect of the convergence moving over Avenal airport by noting the sudden change in wind direction and the jump in potential thermal height when the convergence arrived over the field in the following samples.



Saturday, October 3, 2015


Visibility: Hazy but more than 30 miles
Wind: Northwest at 10 knots
Altitudes: 4000 msl
Time Aloft: Several hours
Max Lift: 6 knots
Temperature: Mid 80's
Comment: Many demo flights.
Tow pilot: Karl Kunz, Jim Rickey, Harold Gallagher


It wasn't a great day for soaring but if one got lucky and encountered lift soon after release, you could remain aloft for several hours. Not too many pilots did that today partly because the lift was fickle, and often narrow, and broken up by the wind aloft. Some demo flights were very good for time aloft and altitude gained but others were short and not too high. That's Mother Nature. We'd like to count on having all our flights be long and high but that's not always in the cards. For some there was disappointment, for others there was the thrill of having been aloft in a glider for the first time regardless of time aloft.

The work goes on for restoring Big Bird. We continue to thank those few who have devoted a large measure of their time to working on the glider rather than flying. Besides Jan Zanutto and Martin Caskey, others are well known around the field and since I don't want to leave out anyone, I'll just say, THANK YOU FROM ALL THE CLUB MEMBERS.

Jan Zanutto spraying the fuselage with the first coat of primer.

Jim Rickey is almost always working on Big Bird when he isn't towing.

We had the Avenal Gliderport Corporation annual meeting this morning at 9:00 am and were finished by about 10:00 am. Mark Neal had arrived hoping to perhaps get someone to fly with him and sure enough Dan Gudgel was able to make several flights with Mark on his way to his license.
Mark Neal waiting for Dan Gudgel to board the glider.
Ed Mandibles running the wing for Dan and Mark.
 One of the stockholders decided to go for a ride since it had been several years since he flew the last time.
Tom Marchione had fun with Dan, staying aloft for enough time to satisfy anyone.
Dan Gudgel doing more demos, this time with Tom Marchione from Los Angeles.
Another demo flight was made by Ethan Ronat for Jeremy who arrived about noon for his flight.

Dan Gudgel and Mark Neal watch as Ethan Ronat prepares Jeremy for his flight.
Now they're ready to launch and the dust devils seem to be getting more numerous.

Around 1:00 pm, the family arrived who had been scheduled for one demo ride. That turned out to be the grandmother, accompanied by her husband, her daughter, and their tiny grandson.

 Of all the people who I meet at the donut shop every morning, this "young" grandmother was the only one to accept the challenge and go for a glider ride. Good for her, and this should embarrass the others to finally decide to "risk all" with a glider ride.

Grandfather, daughter and grandson were having fun on the patio.
Grandmother and daughter walk to the launch area but had to wait for refueling and several launches.
Sergio Grajeda and Ed Mandibles push Carl Engel and his glider into place for a launch.
Our club gliders have already flown this morning and will fly again all day.
Carl Engel waiting patiently for launch but it wasn't to be quite soon.
In the meantime, after walking to the launch area, Grandmother and Daughter had to wait for refueling the tow plane and for the high performance gliders to launch. While waiting they made themselves busy looking at the gliders, and taking pictures.

With Carl out of the glider, what is so interesting that everyone is looking at?
What? A substitute pilot? An invader? A Future Glider Pilot of America?
Nope, just a lovely Grandson not at all dismayed by all the fuss over him.
Now with Carl back in his glider, the launch may not be too far away.
Well, finally, the high performance gliders were all launched and now came Grandmother's turn to fly. She is a great sport, anxious to experience what it's like to fly silently, no engine noise, few bumps, some lift, a bit of gained altitude, and a tour of the Avenal area.

She is absolutely looking forward to this, her first glider flight.
A few words about helping do the release and re-trim the controls and Harold is satisfied she is ready.
One last hug from her Daughter and her pilot will crawl into the backseat.
The launch is underway and Grandmother is going aloft in a glider!! Imagine that!!
Grandmother was not nervous at all and had ample time to take this photo on tow.
Still on tow going past 2250 msl, Grandmother took another picture of Avenal.
Thousands of feet in the air and still on tow behind the tow plane.
Grandfather points out the baby's Grandmother way up in the air. WOW!!
And so the experience ended. Not a lot of lift, nor a lot of time aloft, but the flight was valuable nonetheless. All the elements of a glider flight were present in even a less-than-lengthy flight so Grandmother was happy to have done it for the first time.

Jennifer Bauman brought three of her classmates in Aerospace Engineering from Cal-Poly to take their first glider flights. They all had a good time, not all had stellar flights for time aloft. But that's the nature of glider flying and the odd chance of lift being where you are at any moment.

Andrew Palmer aloft at just after release. We found lift and gained about 1000 feet overall.
Yes, Andrew enjoyed the flight and told the others about his experience.
It's Daniel Stalters' turn helped by Andrew Palmer, Paul Kujawa, Carl Engel, Jennifer Bauman and Jim Rickey.
A great  group of our future leaders of America in technology and other disciplines.
Jennifer, Andrew, Paul, and Daniel in the cockpit.
They are putting away the DG-100 that Carl flew today.
After landing, Daniel Stalters enjoyed the flight as much as Andrew.
Mark Neal stayed on today after his early morning flights to not only help out with the launches but to take a series of really nice photographs. I couldn't use them all but tried to pick out some of the best in his series. He was especially good at shooting the landing sequence of the 1-26 flown by Ed Mandibles.

Nice shot of the Orange Crush quite high at this point. He used a good telephoto lens.
The right turn from base to final for runway 7 at Avenal.
In flight and there were a good series of these shots, all of which could have been shown.
On final, dive brakes opened, for runway 31L, at Avenal, piloted by Ed Mandibles.
Nicely aligned for the runway, Ed kept it under good control.
Just a nice sequence of photos by Mark Neal of Ed Mandible's flight.
About 10 feet or so above the runway Ed is bringing it down slowly and carefully.
That 1-26 is just a good looking glider and very fun to fly as well as mostly forgiving.
Bill Shoemaker had a minor mishap that thankfully occurred on the ground and not in the air. We all breathed a sigh of relief at the outcome. The day was about ending and both he and Carl Engel headed back to the Bay Area soon after.

It turned out to be a very busy day with six or seven demo flights and more flights by students and high performance glider pilots. If you missed today, you missed a good one so plan on being out at Avenal soon. The weather will be superb from now on, likely in the mid-80's so very comfortable on the ground.

See you next week.

Harold Gallagher.