The Napier Eland is a British

turboshaft A turboshaft engine is a form of gas turbine that is optimized to produce shaft horsepower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the ex ...

turboprop A turboprop is a Gas turbine, gas turbine engine that drives an aircraft Propeller (aeronautics), propeller. A turboprop consists of an intake, reduction drive, reduction gearbox, gas compressor, compressor, combustor, turbine, and a propellin ...

gas-turbine engine built by Napier & Son in the early 1950s. Production of the Eland ceased in 1961 when the Napier company was taken over by

Rolls-Royce Rolls-Royce (always hyphenated) may refer to: * Rolls-Royce Limited, a British manufacturer of cars and later aero engines, founded in 1906, now defunct Automobiles * Rolls-Royce Motor Cars, the current car manufacturing company incorporated in ...

Design and development

The Eland was first tested in flight in 1953 in a Vickers Varsity aircraft. Further flight proving was carried out from 1955 using the first production Airspeed Ambassador 2. The Eland was dropped from production when Napier was acquired by

Rolls-Royce Limited Rolls-Royce Limited was a British luxury car and later an aero-engine manufacturing business established in 1904 in Manchester by the partnership of Charles Rolls and Henry Royce. Building on Royce's good reputation established with his Crane ( ...

in 1961. The only production applications for the engine were two variants of the Convair CV-240 family, the Royal Canadian Air Force Canadair CC-109 Cosmopolitan and the civil Convair CV-540. The military and civil operators had perpetual trouble with the engines which were considered complex. Due to their unreliability The Department of Transport reduced the time between overhauls. The CC-106 had its Elands replaced with the

Allison T56 The Allison T56 is an American single-shaft, modular design military turboprop with a 14-stage axial flow compressor driven by a four-stage turbine. It was originally developed by the Allison Engine Company for the Lockheed C-130 Hercules tran ...

turboprop and the CV540 was re-engined with the

Pratt & Whitney R-2800 Double Wasp The Pratt & Whitney R-2800 Double Wasp is an American twin-row, 18-cylinder, air-cooled radial aircraft engine with a displacement of , and is part of the long-lived Wasp family of engines. The R-2800 saw widespread use in many important ...

piston engine. Potential production applications which were subsequently cancelled were the Westland Westminster heavy-lift helicopter and the Fairey Rotodyne gyrodyne. The Rotodyne operated as an autogyro in forward flight using the Eland turboprops. For vertical flight the rotor was driven using an auxiliary compressor clutched to each Eland. They supplied compressed air to a combustion chamber at each rotor tip.

Variants

; Eland N.El.1: + residual thrust, static at sea level ICAN conditions. ; Eland N.El.3: Powerplant for the Fairey Rotodyne driving the propeller and an auxiliary compressor to feed the rotor tip jets + residual thrust, static at sea level ICAN conditions. ; Eland N.El.4: + residual thrust, static at sea level ICAN conditions. ; Eland N.El.6: ; Eland N.El.7: The 504 adapted to helicopter / convertiplane, compressed air generator use. ; Eland E.211: The 504 adapted for mechanically driven helicopter rotors. ; Eland 504:(N.El.6) ; Eland 508: 504 with increased max continuous rating.

Applications

Airspeed Eland Ambassador at Farnborough 1955

Turboshaft

* Westland Westminster

Turboprop

* Airspeed Ambassador * Canadair CC-109 Cosmopolitan (CL-66) * Convair CV-540 * Fairey Rotodyne * Vickers Varsity (one aircraft as an engine test bed in 1954)

Engines on display

A turboshaft Eland is on display at the Helicopter Museum,

Weston-super-Mare Weston-super-Mare ( ) is a seaside town and civil parish in the North Somerset unitary district, in the county of Somerset, England. It lies by the Bristol Channel south-west of Bristol between Worlebury Hill and Bleadon Hill. Its population ...

.The Helicopter Museum - Fairey Rotodyne
Retrieved: 28 July 2009

Specifications (Eland N.El.6)

References

Notes

Bibliography

* Gunston, Bill. ''World Encyclopedia of Aero Engines''. Cambridge, England. Patrick Stephens Limited, 1989. *

External links

Atlantic Canada Aviation Museum - Napier Eland 504 information sheet
a 1959 ''Flight'' article {{Napier aeroengines Eland 1950s turboshaft engines Axial-compressor gas turbine engines