H03-1 S-51 Main Components

Excerpts from the S-51 Manual:

DESCRIPTION:

GENERAL. The model H03S-1 helicopter is a four seat, single engine helicopter accommodating three passengers and a pilot. Helicopters, Navy Serial Nos. 122508, 122509, 122512, 122513, and 122514, have been modified for dual control and accommodate only a pilot and co-pilot. Helicopters BuNos. 1231 18 and subsequent are equipped with flotation gear and a jettisonable auxiliary fuel tank. The purposes of the H03S-1 are short range liaison, observation, performance of courier mission, rescue and miscellaneous purposes for which this type of aircraft is adaptable.

FUSELAGE. Fuselage structure consists of the following three principal separable sections, bolted together: cabin structure, centre section, and tail cone. The engine mount and the transmission mount are located in the centre section.

UNDERCARRIAGE. The undercarriage gear consists of a tripod type, two-wheel main gear and a single nose wheel assembly.

HYDRAULIC SYSTEMS. Four individual hydraulic systems are installed: main rotor damper system, main rotor brake system, main undercarriage gear wheel brake system, and a hydraulically operated rescue hoist.

OIL SYSTEM. The oil system consists of an oil supply tank; an oil cooler; two oil drain valves; pressure and temperature indicators; an oil dilution system; and tubing.

FLIGHT CONTROLS. Flight controls consist of a conventional control stick, a main pitch control, and tail rotor control pedals installed in front of the pilot's seat. There are provisions for the installation of dual controls at the rear seat. On helicopters Navy Serial Nos. 122508, 122509, 122512, 122513, and 122514, the dual controls are already installed.

COMMUNICATIONS. Three radio sets are installed in the helicopter: a VHF transmitter-receiver, a range receiver, and a navigation receiver.

HEATING AND VENTILATING SYSTEM. The heating and ventilating system consists of an electrically controlled heater and a duct system. A plastic nose defroster is also installed.

ELECTRICAL SYSTEM. The electrical system is a conventional 28-volt, direct-current, single-wire type. Energy for the system can be obtained from any one of three sources: belt-driven generator, battery, or external power. The receptacle for the latter is located on the lower aft cone support section.

ENGINE. Power is supplied by a single Pratt and Whitney Wasp Junior, model R-985-AN-5, nine cylinder, air cooled, radial engine.

TRANSMISSION SYSTEM. The engine is connected by a drive shaft to the main gear box, which is located above the centre section of the fuselage. The main gear box is supported by a main rotor and transmission support. The main rotor head receives power through a drive shaft, extending from the top of the main gear box. By a take-off drive and a tail rotor drive shaft, power is transmitted to the tail rotor through a generator drive located in the cone support section of the fuselage.

FUEL SYSTEM. The fuel system consists of two removable metal tanks housed within the centre structure and protected by fire walls; either an external auxiliary fuel tank installed on the right of the centre section, or a jettisonable belly tank; a fuel selector valve and control; an auxiliary fuel pump; a strainer; an engine driven a fuel pressure line; an engine primer; and tubing.

Fuselage layout