If we could somehow identify or "paint" turbulent air.
In the 1990s, I was involved in a lengthy UCLA/UCOP White Mountain Research Station logistics support project for a group of scientists from Allied Signal who were doing just that. At least one had worked directly on the repair of the lens of the Hubble Space Telescope. They had developed an optical device for the Space Shuttle to detect turbulence on re-entry and avoid it by changing the glide path. Each winter afternoon, I took them to Mt. Barcroft, south of White Mountain in Owens Valley, via a Tucker Snocat where they would spend hours testing and calibrating the instrument.
But for practical purposes, in hang gliding, the technology behind Alan Fisher's Thermal Snooper hasn't been beat since my prototype testing in the Owens Valley in 1987.
Wow! Pretty interesting, Rick. I can picture your launches from Mazurka Peak from my being up there last year and imagining myself running off the mountain under a HG.
I can only imagine how well that thermal sensor would have worked in conjunction with the extremely fast response and very high sensitivity of my Colver variometer. Too bad I had retired from the vario business before it came along, or I would have definitely paired them.
Model glider flyers and free flight modelers have used thermistors, mounted on poles upwind in the field, for many years to detect a thermal coming across the field to time launches.
After flying with it for a while, I started thinking of the vario and the thermal snooper as one instrument - the instrument that should have been built back then. That instrument would have employed a pressure variometer and a temperature variometer with audio output. Today a visual mapping feature could be added, using GPS and telcom linking gliders, that could be used by cross-country pilots travelling together. A thermal map could be generated by the gliders in flight, showing thermal activity or sink (via the pressure variometer) and potential thermal proximity or lack thereof (via the temperature variometer) along the flightpaths of the participants by combining the data, visualizing it and sharing it on the instrument cluster display of each pilot. Can you imagine what a cross country contest would be like using this equipment? Pilots would flock to the strongest thermal, climb, race away and spread out, then repeat. It would also indicate the best paths for dolphining. I do not see how it could not result in the longest cross country flights in history.
This hang glider pilot is flying with a Thermal Snooper. I can't vouch for his technique but I'm glad he posted these on YouTube so you can get the idea of what it's like flying with one.
The US Nationals sailplane champion at the time, Peter Masik, fitted a Thermal Snooper to his sailplane but, for him, the results were inconclusive. I am certain it was due to the higher speed of the sailplane. Alan Fisher designed the instrument for the slower speeds of hang gliders. The hang gliding community was offered a spectacular opportunity but completely dropped the ball. You can't even find a Thermal Snooper today.
When using the Thermal Snooper to locate sloughing thermals, the same techniques are used as when locating thermals with a vario. The Snooper and vario work in unison, enhancing the likelihood of finding lift. Think of them as one instrument. The Snooper is the more sensitive aspect of this device. It tells you a thermal is nearby. The vario tells you when you are actually touching the thermal. It verifies your guess. The Snooper will "beep" when it senses the warm eddies sloughed from the thermal (1). If the "beeps" stop, immediately execute a 270 degree turn that leads back to the central point of the beeping (2). Regardless of which way you choose, you will intersect the thermal. The Snooper will continue to beep as you approach the core, but the vario and tactile feedback must be employed to center it (3).
I flew almost exclusively with one of Gilbert Robert's very responsive breadbox vario/altimeters that I bought from him in the early summer of 1981. I mounted a lovely new Hamilton Vertical Compass, earphones and a strobe light into it. It stuck out in front about 18 inches and you'd rotate it up to land. In 1986 I added a Thermal Snooper. Last time I checked, everything still worked - 34 years later!
"The Hamilton Vertical Card Compass is a dry compass, designed to replace the float/liquid type compass. -- no more leaking fluid or backward azimuth readings. It uses eddy current damping and as such has no overshoot. Consists of a 2" vertical rotating dial which is compared with a fixed miniature airplane (lubber line) to present the magnetic heading of the aircraft at all times. Heading information is more natural because the heading is read at the 12 o’clock position and off the nose of the miniature aircraft. The compass card rotates and presents all quadrants in their true relation to line of flight. Requires no power (except for lighting) to operate. Fully TSOd. Installed in many current production aircraft & helicopters. Size: 2-7/8"H x 2-3/8"W x 2-1/8"D. Wt. 0.6 lb. Also suitable for use in sailplanes."
The first few years I flew hang gliders, I flew religiously with a Hall Wind Speed Indicator and a yaw string. But when I transitioned to bowsprits, I never used the WSI again. Funny, I realized I was never looking at it anymore so I ditched it. I always flew with the yaw string, though.
When I started flying the Owens Valley on a single surface Seagull 10-meter variant, a deflexored Spectra Zodiac designed by my hang gliding mentor Carlos Miralles http://www.pbs.org/saf/1109/hotline/hmirales.htm, I did not have a variometer. I learned to work big thermals by feel. Don Partridge taught me a parallax ascension technique that seemed to work pretty good with the big mountains nearby. My altimeter was out of one of the B-24s my dad flew in WWII. I was really pretty satisfied with that until I got a vario.
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by dhmartens » Tue Sep 08, 2015 5:52 pm 
