Hillberg EH1-01 RotorMouse

The Hillberg EH1-01 RotorMouse is an American helicopter that was designed by Donald Gene Hillberg and produced by Hillberg Helicopters of Fountain Valley, California, first flying in 1993. Now out of production, when it was available the aircraft was supplied as a kit for amateur construction.

Design and development
The EH1-01 RotorMouse was designed to comply with the US Experimental - Amateur-built aircraft rules. It features a single main rotor, a two-bladed tail rotor, a single-seat enclosed cockpit with a windshield, skid-type landing gear. The acceptable power range is 145 to 250 hp and the standard engine used is a 145 hp Garrett AiResearch 36-55 auxiliary power unit (APU).

The aircraft's semi-monocoque fuselage is made from 2024-T3 aluminum sheet. Its 20 ft diameter two-bladed rotor employs a NACA 0012 airfoil. The aircraft has an empty weight of 635 lb and a gross weight of 1300 lb, giving a useful load of 665 lb. With full fuel of 33 u.s.gal, located in a crash-resistant fuel cell, the payload for pilot and baggage is 441 lb. The cabin width is 24 in and the aircraft mounts stub wings similar to the Bell AH-1 HueyCobra.

Operational history
By 1998 the company reported that one aircraft was completed and flying.

By March 2015 one example had been registered in the United States with the Federal Aviation Administration. The sole one on the registry was in the name of the designer.

Variants

 * EH1-01 RotorMouse
 * Single seat version, one completed


 * EH1-02 TandemMouse
 * Proposed two seats-in-tandem version to resemble the Bell AH-1 HueyCobra. It was proposed to have been powered by a Solar T-62 turbine engine of 150 hp.