Hang gliding 1977
This page follows Hang gliding 1976 part 2.
The images on this page are my artistic derivations of contemporary photos. See Copyright of early hang gliding photos.
On June 24th, 1977, Bob Wills of Wills Wing was killed when his hang glider was struck by the down-wash of a helicopter filming him for a Jeep advert. Rob Kells, Steve Pearson, and Mike and Linda Meier took on the development of Bob’s latest design, and Wills Wing continued as one of about sixteen major hang glider manufactures in the USA. (1)
Wills Wing re-used the name Cross Country for their popular 1995 wing.
See my related topics page Sport Kites/Wills Wing of California.
The damage in this incident was limited to the power line and the glider.
Jim and Henry Braddock were second and first, respectively, at the U.S. national championships held at Heavener, Oklahoma, in July 1977. (Heavener rhymes with heathen, not heaven, apparently.)
Powered hang gliding was going through its early stages at this time. (See Early powered ultralights in Powered flight.) It brought problems additional to those inherent in hang gliding. The man standing and speaking in the following picture is hang gliding photographer and columnist Bill Allen.
The original photo by Jim Theis, on which this artistic rendering is based, is of Dan O’Neil dune-soaring an Electra Flyer Cirrus 3 in a gale on the dunes at at Boca Raton, Florida, during tropical depression Anita in August 1977.
Grouse Mountain, where Leroy Grannis took the photo on which this image is based, overlooks the city of Vancouver, Canada.
Hang gliding was still regarded as a spectator sport in the late 1970s. Here is a snippet about pilots John Davis and Glenn Hockett and competition promoter Don Whitmore:
Davis and Hockett and Whitmore were interviewed for national TV, and the remaining pilots packed their gear in the warm late afternoon sunlight. The city of Vancouver was shining, the ships in the bay swinging into the seabreeze.
— Hang glider pilot and English teacher W.A. Roecker writing in Hang Gliding, September 1979
Former movie actress Bettina Gray travelled the world to photograph hang gliders and her shot of the Skyhook Sunspot on which this artistic derivation is based shows the shape of the sail in flight.
The wing that Ash is flying in this picture is a Birdman Moonraker.
When British manufacturer Birdman of Marlborough, Wiltshire, developed the Moonraker with its low-billow sail and chord-wise battens, Roly the sail-maker took the opportunity to upgrade their ‘intermediate’ level glider, the Firebird. He replaced the radial battens (which stay in the sail when the glider is de-rigged) with five chord-wise battens each side, resulting in an appearance similar to the Electra Flyer Cirrus 3. They designated the new version Firebird S. It had much improved performance, but the umbrella-like quick rigging of the original Firebird was gone.
Ken Messenger of Birdman and competition organizer Brian Milton attempted to cross the English Channel in their Moonrakers by first being lifted to altitude beneath hot air balloons. Milton released at 14000 ft and ditched into the channel to be picked up by a Russian ‘trawler.’ (This was during the cold war.) Its crew took some persuading that Milton was a ‘sporting man.’ Messenger released at 20000 ft to land in the same field in France from which Louis Blériot had taken off for the first ever flight across the channel nearly 70 years before. Meanwhile aboard the balloon that had lifted Ken in his hang glider to altitude…
On the way up I got my oxygen equipment tangled up when I was changing cylinders, so I was without oxygen at about 15,000 feet for a while, which gave me a bit of a headache… I was on top of a cloud. It looked so solid… I felt I could get out and walk on it. I had a terrific urge to get out and walk on the cloud!
— Balloon pilot David Liddiard (2)
See my related topics page Birdman of Wiltshire, England.
Aspect ratio, or span divided by average chord, measures the spindliness of the glider. More span provides greater efficiency, in principle. In practice, however, increasing span incurs problems in controlling the washout (span-wise twist) of the sail and it also imposes higher structural loads and it can incur handling problems.
In 1977, Electra Flyer added the state-of-the-art Olympus to their successful Cirrus series of wings. See my related topics page Electra Flyer of Albuquerque, New Mexico.
At first we had hoped to conduct strength tests using a car-top aerodynamic loading system, but we were warned by the experience of UP and Albatross in America that any test done in this manner tends to result in a large pile of scrap after the smallest fault develops in the glider. We therefore opted to test the strength of the glider by a static loading method (as is used for conventional aircraft).
— Steve Hunt of Hiway Hang Gliders writing in the BHGA magazine Wings, September 1977
As the airframe and sail distort, the washout distribution changes, which guides you in where to place the next sandbag. According to Hiway Hang Gliders, the crosstubes of the glider were first to fail, by Euler buckling.
Notice in the Albatross test that the control frame down-tubes, which are normally straight, are bending under compression. Straight edges in the background are straight, so the curvature is not merely a photographic effect.
While sandbag testing of single surface gliders suspended upside-down is effective, there is a particular problem with sandbag testing of double surface sails: You cannot reach the underside of the upper surface to put sandbags on it. Even if you could — and even if there was enough room — how many sandbags should you place on the lower surface to add an ‘upward’ (downward in the Hiway upside-down test) force on the cross-tubes?
That was one impetus behind hang gliding associations in several countries creating structural test rigs subsequently.
This topic continues in Hang gliding 1978 and 1979 part 1.
Ashley Doubtfire, legendary hang gliding instructor, on British Hang Gliding History, which includes text I contributed in 2017
1. Mike Meier, Wills Wing–The Early Years in Sky Adventures, Legends and stories About the Early Days of Hang Gliding and Paragliding edited by Jim (Sky Dog) Palmieri and Maggie Palmieri, 1998
2. Farmer, rally driver, balloonist, and airship pilot David Liddiard interviewed for Barley & Balloons, David Liddiard remembers, by Jennifer d’Alton, 1998