Dyke Delta

The Dyke JD-2 Delta is an American Homebuilt aircraft designed in the United States in the 1960s and marketed for amateur construction. It is a monoplane with retractable tricycle undercarriage and seating for four. The wings can be folded for towing or storage and hinge upwards to lie flat above the fuselage, one atop the other. Construction is of SAE 4130 grade steel tube framework with fiberglass and fabric skins.
In its standard configuration, the aircraft is a true double-delta with no horizontal stabilizer; however, a small T-tail is an option for trimming variants with higher-power engines. Since the mid-1960s, designer John Dyke has sold the aircraft plans to homebuilders. No kits were ever marketed. Over fifty examples have been completed.
Development.
Designer John Dyke said his inspiration for the aircraft came from Alexander Lippisch's delta designs, specifically the LP-6 glider and later the Convair F-102 Delta Dagger. The double delta layout of the Saab 35 Draken was incorporated into the design. A lifting body fuselage was incorporated after tests.
For research into the proposed layout, Dyke built models mounted on the front of his car and flew radio-controlled models to determine aerodynamic qualities. When the original Dyke JD-1 Delta was destroyed in a garage fire, after 145 hours of flight-testing, his wife persuaded Dyke to build an improved version as the Dyke JD-2 Delta.
The Dyke Delta JD-2 flew for the first time on July 18, 1966, with the prototype flying more than 2,000 flight hours over a span of 40 years.
Design.
The aircraft is metal framed with skin of laminated fiberglass or covering of Dacron fabric.
It has retractable landing gear.
The delta configuration offers a relatively high cruise speed compared to conventional aircraft of the same weight and power and a relatively high stall speed of 70 to 75 Mph. Approach speeds range from 110 to 100 mph with a flare at 70 mph.
Operational history.
Including the prototype, under a dozen are in a known flying condition today, though nearly that many are currently under construction.
The Dyke Delta was involved in NASA-funded flight-testing . Kelly Aerospace towed the Delta behind another aircraft to obtain flight towing and engine-off (glider) controllability data for use on future space-travel designs. The Dyke Delta flew quite well in tow and in a glide. Over the years, the JD-2 structure was evaluated by the University of Utah and the Wright Patterson Air Force Base (Ohio) Structural Laboratory. 
Variants.
The JD-2 was preceded by the JD-1 Dyke Delta, a slightly smaller version that was lost in an accidental garage fire on June 4, 1964, after about three years of service. Portions of the JD-1 were used in constructing the JD-2.
The Delta Stingray was a one-off development effort by Dyke, utilizing wood construction for the single-place airplane. It was flown for nearly 30 years before being retired to a museum.