Tony asked Everard about the Gryphon, and a plan view drawing was quickly done on the only plain white paper readily available.
A year later a digital sequence of plan views became a short section in Everard's Hang Gliding Ground School, a computer-based hang gliding theory training program. This led to The Evolution of the Flexwing, an article in the BHPA's magazine SkyWings, in October 1992. Much of its content is incorporated in this history.
During the late 1970s and early 1980s the author, an amateur artist, created more than fifty hang gliding paintings. Most are based on small black-and-white photographs printed in the USHGA's magazine Hang Gliding and its forerunner Ground Skimmer. Together with images from Hang Gliding Ground School, digitised photographs of those paintings constitute a ready source of illustration for this history. There are, at the time of writing, few quality early hang gliding photographs whose copyright holders can be traced in order to obtain permission to use those images in a work such as this.
More recent illustrations are provided by the author's wing-mounted camera, a Ricoh FF-9, and a ground-based Olympus OM-10 SLR with a zoom lens and tripod.
Additionally, photographs of modern 'class two' (rigid) hang gliders and powered ultralights have been provided by hang glider pilot and historian Justin Parsons.
Wessex club paraglider pilot Mike Adkins travelled the California coast in July 1978. There he took a number of photographs of hang gliders with his 110-format camera -- using slide film. The photos of the Icarus II / Easy Riser and the Electra Flyer Olympus' came from that collection.
During 1976 early Wessex hang glider pilot Dave Lewis took a number of photos, using 35mm slide film, of hang gliding action in the region. Selected images from Dave's collection are used in the two pages titled Kimmeridge Khmer Rouge.
Thanks to Wessex Hang Gliding & Paragliding Club web-master David Daniels for digitizing Dave's and Mike's original transparencies.
Hang glider designer Len Gabriels provided digitised photographs and history of his firm Skyhook Sailwings (of Oldham, Lancashire, England) and a summary of his background and other inventions.