HELI-EXPO: Rolls-Royce adds FADEC, power boost to venerable Model 250

Las Vegas
Source:
This story is sourced from Flight International
Subscribe today »

Rolls-Royce is bringing a full authority digital engine control (FADEC) to the 700shp (522kW)-class commercial helicopter engine market.

The Model 250-C47E Evolution unveiled at the Heli-Expo convention in Las Vegas features a dual-channel FADEC, says R-R senior vice-president of helicopters Greg Fedele.

It helps the latest variant of the M250 series deliver a 7.7% thrust increase compared with its predecessor, the M250-C47B/M, with power margin to spare if a manufacturer requests more thrust, he adds.

The drop-in re-engining candidate is also designed to reduce direct operating costs and fuel burn, Fedele says.

It also represents the latest advance for FADEC technology into ever-smaller applications, where once the units were too expensive to justify the improvement in response times and flight management.

Pratt & Whitney Canada's rival PW200-series engines, by contrast, feature a single-channel electronic engine control (EEC). An EEC differs from a dual-channel FADEC because it uses a less precise hydro-mechanical back-up system if the digital controls fail. However, EEC reliability has improved so much that it is essentially considered a fully digital system by the market.

P&WC has integrated FADEC controls into turboshaft engines at slightly higher power levels, but has no plans to replace the EEC with a FADEC in the PW200 series, which offers engines in the 500-700shp range.

Instead, the engine manufacturer has rolled out new reliability improvements for the PW206 and PW207 turboshaft engines, extending the time between overhauls.