The HRH was designed to comply with the US
experimental – amateur-built rules. It features a single main rotor, a single-seat enclosed cockpit with a windshield, skid-type
landing gear and a four-cylinder, air-cooled,
four-stroke,
Subaru EJ25 automotive engine. It is the high power to weight ratio that gives the aircraft its name. The aircraft
fuselage is made from a mix of welded
4130 steel tube and bolted-together
aluminum tubing, with a composite cabin shell. Its diameter two-bladed Waitman composite rotor has a chord of . The tail rotor has a diameter. The aircraft has an empty weight of and a gross weight of , giving a useful load of . With full fuel of the payload is . The HRH can hover in ground effect at and out of ground effect at ==Operational history==