Text by Steve Leonard
Pictures by Dick Russell
This HP-12A located in Kansas now belongs to Dick Russell. It is the one Dick Johnson built. It was always refered to on the contest circuit (near as I can tell), as an HP-13M.
Editor's Note: Dick performed numerous flight tests on this bird. A copy of these tests were recently forwarded to the Schreder website by Jeff Casto.
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The fuselage is that of an HP-11A. The wing has been raised 5.5 inches (I believe) to put the wing at the top of the fuselage. At the time, it was believed that this wing location would provide the lowest overall drag. The tail feathers have been modified. The moveable portion was extended about 14 inches beyond the tip rib, providing increased control surface area and a aerodynamic balance to reduce the overall control forces. The tail feathers are also removable. Dick made a very clever tongue and groove arrangement for the main spar and used what looks to be very similar to the Schreder original fittings at the front. Each surface is held on by two spring loaded pins.
The wing is an extended, beefed up HP-14 wing. Three feet was added to each tip, beyond the aileron. The aileron was not extended. An interconnect system has been added to be able to raise or lower the ailerons to match the flaps in an effort to improve the higher speed and thermalling performance of the ship.
The ship has integral water ballast tanks in the wings. The tanks are the leading edge of the wing for about the first 5 feet from the root. The lightening holes at the end of the tank are covered with a riveted on aluminum cover. There is a fill port (with vent holes) in the top surface, just inboard of this rib, and just ahead of the spar. The drain for the tank is a tube sticking through the root rib just ahead of the spar. I do not think there has been any water in the tanks for many, many years.
It was sold by Dick Johnson to a club in Minnesota in 1974. They owned and operated the ship until 1983. The ship was assembled in the Spring, and one of the ruddervators was not properly engaged. The aircraft crashed on takeoff. Bob Park bought the plane and repaired it. He flew it for a few years before selling it to Gary Trimpe. Gary is one of our hang glider converts.
Gary put a great deal of effort into the glider and the trailer, fixing things up, re-contouring the nose, and adding a retractable, steerable tailwheel. Gary got out of soaring and sold the HP back to Bob. Bob flew the HP (wining our clubs Kowbell Klassic contest a number of times with it) until he sold it to Dick Russell.
I guess once an HP comes to Kansas, they never leave. They just change hands.