Enstrom 480

Design and development

In the 1980s the Enstrom Helicopter Company was producing two helicopters, both powered by horizontally-opposed piston engines. When the United States Army revealed a requirement for a turbine-powered training helicopter, the company designed a larger, turbine-powered version of its 280 Shark. The proposed unit was designated TH28 (TH for "training helicopter" derived from the 28(0), since the Army's proposal was NTH, "new training helicopter").

The Army contract effort was not successful, but the company effort looked promising enough that management committed to continue with a commercial version, which was introduced in 1993. Its power was provided by the C20W variant of the Rolls-Royce Model 250 turboshaft engine.

Design

The 480 fuselage consists of a welded steel-tube framework with aluminum cover and tailcone. The pilot controls the aircraft from the left seat, which is unusual for helicopters. The aircraft does not have a hydraulic system; a trim system absorbs rotor feedback and allows the pilot to position the desired stick setting. The 480B engine is capable of producing 420 shp, but in this application it is limited to 305 shp for 5 minutes and 277 continuous shp, which is available to 13,000 MSL on a standard day. Thus hot-temperature or high-altitude operations have a considerable degree of confidence. The engine drives a three-bladed rotor of 32 feet diameter and a tail rotor of 5 feet diameter. The main rotor and hubs weigh a total of 300 pounds, so there is considerable inertia in the system during a loss of power. Autorotation landings are uneventful.

Variants

480

Five-seat civil version based on the Enstrom TH-28, certified in November 1993.

480B

Enhanced and with increased gross weight (3000 lb) and power limits, certified in February 2001. The gross weight and useful load were increased by approximately 150 pounds.

480B Guardian

480B configured for police or law enforcement operations, fitted with a front-mounted camera and searchlight.

TH-28

Based on the Enstrom 280FX with a turbine engine, a larger cabin and larger horizontal and vertical stabilizers. Certified in September 1992 Military training, light patrol version, six built.

Civil operators

The aircraft us operated by a large number of small commercial and flight training operators, most operating one or two aircraft.

Former

 Canada

York Regional Police

Military and government operators

 Equatorial Guinea

Military of Equatorial Guinea

 Estonia

Estonian Environmental Inspectorate

 Indonesia

Indonesian National Police

 Japan

Japan Ground Self-Defense Force

 Thailand

Royal Thai Army

 Venezuela

Venezuelan Air Force

Specifications (480)

Data from The International Directory of Civil Aircraft, 2003-2004

General characteristics

Capacity: 5 total

Length: 29 ft 10 in (9.09 m)

Main rotor diameter: 32 ft 0 in (9.75 m)

Height: 9 ft 7 in (2.92 m)

Main rotor area: 804 ft² (74.7 m²)

Empty weight: 1,675 lb (760 kg)

Gross weight: 2850 lb (1,293 kg)

Powerplant: 1 × Rolls-Royce Model 250-C20W turboshaft, 285 hp (215 kW)

Performance

Range: 435 miles (700 km)

Service ceiling: 13,000 ft (3,962 m)

Rate of climb: 1,500 ft/min (7.62 m/s)