Explorer PG-1 Aqua Glider
One of the very few waterborne gliders, the Aqua Glider single-seater is also unusual in being a biplane; it is intended for tethered gliding by unlicensed pilots, and is towed behind any speedboat that can attain a speed of 30kt (35mph). The pilot can also cast off from the speedboat when airborne and make a free flight before landing back on the water, but to do this he must have a licence. The Aqua Glider was designed by Col William L. Skliar, USAF (Ret'd), who began design work on it in September 1958, the prototype making its first flight in July 1959. After making about 1,000 flights and being flown by about 60 pilots, the prototype was donated to the Experimental Aircraft Association Museum in Milwaukee.
Approximately 1,000 sets of plans have now been sold to amateur constructors in more than 20 countries all over the world, and about 200 Aqua Gliders were under construction; about 12 are known to have flown, in the Bahamas, Brazil and Japan as well as in the USA. The forward staggered single bay biplane wings are conventional single-spar wooden structures with fabric covering, and there are spoiler-type light alloy ailerons on the lower wing only, immediately behind the main spar.
Balance floats - basically just plate-type fairings - are carried at the extremities of the lower wing tips. The pilot sits in an open cockpit in the unstopped watertight wooden hull and, instead of a conventional planing bottom, take-offs are made on a pair of standard jumper skis, 6 ft in length, attached to small wire-braced struts below the hull. The latter is of spruce with a mahogany plywood bow, bottom skins and sides, the plywood being glass fibre covered below the waterline. There is a towing hook on the nose. The wire-braced tail unit is of spruce with plywood and fabric covering, and is carried on a boom of welded steel tube or wire-braced wooden construction. The rudder is conventional and the tailplane an all-moving one-piece surface.
Span: 4.87m / 16 ft
Wing Area: 14.28 sq.m / 95 sq.ft
Aspect ratio: 5.0
Airfoil: NACA 4412
Length: 13 ft 8 in
Height: 5 ft 0 in
Empty Weight: 83 kg / 180 lb
Payload: 100 kg / 220 lb
Gross Weight: 182 kg / 400 lb
Wing Load: 20.61 kg/sq.m / 4.5 lb/sq.ft
Max speed: 65 mph (in smooth air)
Stalling speed: 35mph
L/DMax: 6.5 at 72 kph / 39 kt / 45 mph