[Frank Colver]

Every once in a while I dig through my old HG boxes and files and I see things that I didn't remember were there. So I decided to participate in this HG history section by starting this section to deposit copies of drawings or photos pertaining to the Skysail and Variometer, my two contributions to what with the passage of time became part of the sports history.

Some items may already be in other sections of the US Hawks forum but this will eventually be a concentration of the historical stuff pertaining to those two original designs.

The first item deposited here, I stumbled across today, is a copy of a three view drawing I made when the Skysail was one year old. I did not remember that I had made this drawing.

As noted on the drawing it is scale 1 foot = 0,2". The background grid is 0.2" squares.

Frank Colver

Skysail 3 view 1-10-73.PDF

(764.73 KiB) Downloaded 474 times

[Frank Colver]

Here's the variometer production line in the early days.

Vario Production Line spring 1974 R.jpg (229.73 KiB) Viewed 7396 times

[Frank Colver]

Skysail frame plan. Drawn in 1971 and photo copied with notes in 2013.

Photo is Ernest Feher at the controls in Spring of '74 at the "Vineyard Rd" hill site in San Marcos (we called it Vista at the time). This was a Richard Miller flying site. The hill is still undeveloped but the landing area is covered with houses. A cement water tank on top has since been demolished.

Note: Photo shows parallel bars which was the last design configuration the wing took. much easier to ground handle.

I can't believe I taught myself to fly (but I did) on this wing, which was a sports car compared to the other gliders at the time I was learning in early '72.

Frank Colver

Skysail frame plan reduced.jpg (516.34 KiB) Viewed 7390 times

Ernest in Skysail - Vista '74.jpg (286.68 KiB) Viewed 7389 times

[Frank Colver]

An early production version of the vario. Judging by its condition this was most likely one I got back for repair. Maybe it's the one that fell 1500 feet at Elsinore and survived by going through a high bush. Its owner located it by hearing the tone it was sounding as it lay under the bush.

[Frank Colver]

A show card to identify the Skysail at a show in early 70's.

Frank Colver

Skysail show card.JPG (263.98 KiB) Viewed 7388 times

[Frank Colver]

Letter from Glenn Bowlus returning a photo (Skysail) he borrowed after the Montgomery meet in July '73.

It's interesting that he was wanting to establish a flying site on Irvine Ranch land at the time. I had forgotten about that. It never happened.

Frank Colver

Letter from Glen Bowlus.JPG (351.86 KiB) Viewed 7388 times

[Frank Colver]

This is top secret information declassified as of now.

This is the schematic of the latest model #6 (model 7XC) that was produced and the one that Wills Wing produced after I turned over the production rights to them. I went on to design one that used a 9v battery, instead of four AA cells, and used much less current, but it was never produced. In that model I changed from the sensor bridge being a voltage divider to a constant current feedback divider. It exhibited less drift over time and a more linear output.

Frank Colver

Last Production Model 7XC Schematic.JPG (441.5 KiB) Viewed 7376 times

[Frank Colver]

More top secret information declassified now.

The sensors were dual "hot wire anemometers" that had to heated elements positioned next to each other in an airflow from two nozzles and air exiting or entering a bottle due to ascending or descending would flow through these nozzles. The wire in the air stream shadow of the other wire would not cool as much as the wire facing the air stream and the balance of the bridge would shift. Thus the wire changing the most would indicate whether air was entering (descending) or leaving (rising) the insulated bottle.

The sensor elements were the filaments of tiny lamp bulbs. I developed a system where I could break the bulbs to expose the filaments to ready the lamps for construction of the sensors. If the manufacturer of the lamps didn't make a gas tight crimp between the wire and the filament then the tungsten filament would oxidize over period of time and the contact would fail. This was the main cause of "infant mortality" in new varios. In order to weed out as much of this problem as I could, in a reasonable amount of time, I would bake the newly exposed bulbs in a low temperature oven overnight and then they would sit for a couple of weeks. When I was ready to start using them, I would run each one through a test system. Not only did it identify bad parts but I also paired them, within certain parameters, to use in the sensor assemblies. There were times when I would have to trow out about half of the bulbs. Obviously, over time, I determined the most reliable manufactures to purchase from.

One German lamp manufacture claimed to weld the filament to the wire posts. Those were very expensive lamps but I figured that if I didn't have to trash any I would be ahead in the long run and fewer varios would experience failure. It turned out that I had a very high failure rate when testing those lamps. When I told the sales rep that the connections were not getting welded as claimed, the factory replied that was impossible because it was done automatically by machine and therefore could not be in error (hmm.... sounds typical German design philosphy doesn't it?). The factory didn't even check to see if there might be something to what i was claiming. Just blind faith in their automatic process to work correctly. Of course I quit buying those lamps.

Frank Colver

Filament Test System.JPG (536.48 KiB) Viewed 7376 times

Filament Test Current.JPG (345.15 KiB) Viewed 7376 times

[Frank Colver]

Here are photos taken during Skysail construction in 1971. Construction started on November 5, 1971 and the wing was first taken out to fly on January 22, 1972. The up only ailerons were quickly abandoned in favor of tip drag rudders when it was discovered that the glider wanted to pitch up when a turn was initiated.

Frank Colver

Building the Colver Skysail 1 R.jpg (537.91 KiB) Viewed 7366 times

Building the Colver Skysail 2 R.jpg (643.9 KiB) Viewed 7366 times

[Bob Kuczewski]

A review of Big Blue Sky posted on the Oz Report features the Colver Vario:

Big Blue Sky
The Hang Gliding pioneering movie

Harry Sudwischer <harry> writes:

“Big Blue Sky” Dreams, Fears, Joy and Tears

Bill Liscomb has managed to reach down into the part of my brain that holds all the emotion I’ve accumulated since I first wanted to leave the Earth and Fly.

The collection of restored 8mm home movies, stills, interviews and the reporting of first-hand participants had me enthralled. Waves of memories dimly recalled have been restored to me. It’s as though a Veil of Gauze was brushed away and I was there rediscovering the most significant moments of my youth. Powerful recollections of the time when I and untold thousands of dreamers realized that the gift of personal flight was there for anybody to take.

The stories of the rediscovery of Hang Gliding includes the context of the 1970’s and the realization that society was ready for this leap of personal freedom. Of course with that freedom came personal tragedy as a movement into the sky for so many included the loss of friends and loved ones. Today we still suffer the loss of friends but not to the extent and scale of the early days of what was sometimes seen a "Death Sport."

The narrative is California centric with a nod to the Eastern pioneers but basically that’s the way Hang Gliding really developed. I got my inspiration from “Low and Slow” and "Ground Skimmer". My enthusiasm for being a Man Bird knew no bounds. Every couple of weeks another publication arrived in the mail and leaps of imagination, techniques, new radical ideas flowed like a drug into my brain. My personal journey included discovering local Hang Gliding junkies by accident. Driving along the Long Island Expressway on my way to work in September 1974 I saw to my amazement 4 or 5 colorful kites in a sand pit to the side of the highway. Forget my job I stood on the brake and swerved off the next exit backtracked to the sand pit and so ended my rational ordinary life. Everybody in that sand pit was as addicted to the notion of personal flight as I was.

The film is true to the feel of the times. Maybe it is best appreciated by those who lived the dreams of the pioneers of Hang Gliding. Fear was also present, when I first found myself thousands of feet above the ground at Mittersil Ski Area in New Hampshire in August of 1975. Hanging under a 43 pound Wills Wing 20/20 Swallowtail Standard Kite with my recently purchased Colver vario screaming UP UP UP. I had the same thoughts as expressed by Sky God Taras Kiceniuk flying his Icarus spiraling up into the big blue sky: "what am I doing here". I wasn’t alone in the sky that day. Just off my left wingtip was Terry Sweeney in the new Sky Sports Kestral. He proceeded to get even higher than me and went XC upwind several miles from the mountain before landing.

My fears of that flight were overcome later that day by joy when it sunk in what I had just done. The next morning I met Tom Peghiny in the LZ at the base of the Ski Slope. I told him I was impressed with the Kestral that he and Terry Sweeney had developed. He was all enthusiastic about the gold colored Colver audio vario hose-clamped to my control bar. I was in the presence of the "Sky Gods", great fellows who shared all they knew and reached out to help anyone who asked for help.

So it continued. I met Stu Smith “Future Sky God” that very same weekend. We rode up the ski lift and he was pumping me for flying tips. I guess he thought I knew what I was doing when all I really knew was how to hang on really tight and let the sky have its way with me. I was extremely lucky to have lived and survived those early days. My tears came years later hearing of the death of Stu Smith at Grandfather Mountain. Stu, a champion gymnast, became disconnected from his wing while doing aerobatic maneuvers and was not able to hang on, I cried again last night.

I am grateful Bill Liscomb was able to capture the time of my and many of my friends lives in this important work of love. It faithfully focuses on the passion of those heady early days. The story is now frozen in time. We can all revisit it and remind ourselves how we really Left Earth.