[JoeF]

Our forum has some notes on the Hawk hang glider by Percy Sinclair Pilcher. See the fertile Pilcher thread HERE which includes some fundament Hawk notes and resources. But this heron dedicated discussion thread invites a close study on the Hawk. He had other gliders, but this topic thread invites profound study of the Hawk, his fourth glider: "soaring machine". He intended some modifications of the glider Hawk for powering under a 4 hp engine, but such version never materialized as a flight breakage in Hawk glider resulted in a crash that resulted in his passing.
Some starter source links:
National Museum of Scotland, at Edinburgh
Percy Pilcher
Pilcher's monoplane gliders "Pilcher completed work on four gliders between 1895 and 1899: Bat (1895), Beetle (1895), Gull (1896), and Hawk (1896)" and regarding the Hawk: "It was the only Pilcher aircraft to include a wheeled undercarriage."
A video below:

Another video

=======================================
Some talking points:
Tail not always being shown, it seems. What is going on with the tale of the tail. Touched-up photographs? Final flight: tail breaking? His patent word choice: "rudder" ... and he noted horizontal only or horizontal and vertical choice ....
Aerodynamic effects of big hole at center of the "two" wings
Aerodynamic effects of body position during flight
Was sister's photo ever of a towing? Did she ever glide off tow?
Pilot's postures
Two king posts and two queen posts? His patent refers to "masts."
Approximal triangle landing gear (not flight control, as he was postured up at plane level)
His related patent: GB189609144 (A) ― 1897-03-06 There are 13 pages including drawings. "Pilcher's Improvements in Soaring and Flying Machines"
We pilots of HGs per Pilcher would be "aeronauts."
He considered the Hawk made of "two wings" generally in one approximate plane. A bird features two wings, a left and right wing.