The Longitude super mid-size aircraft will be powered by the Snecma Silvercrest, a clean-sheet 8,500-12,000-lb.-thrust turbofan that promises 15% better specific fuel consumption than current engines in this thrust class, along with a 50% margin to CAEP/6 NOx limits and 20% margin to Federal Aviation Regulations (FAR) 36 Stage 4 noise limits. It will be rated for takeoff up to 11,000 lb.
The deal with Cessna, signed only recently, represents the first acknowledged application of the Silvercrest. The engine is also to power the Dassault SMS, which has not been formally launched, and will be a larger aircraft than the Longitude. Assembly of the first new Dassault Falcon is set to start next year, with first flight in 2014 and entry-into-service expected around 2016. The aircraft will feature a Honeywell cockpit.
Ground trials of the first Silvercrest engine are due to begin this summer as Snecma works to begin flight trials of the business aircraft engine in the first half of next year.
The Silvercrest design covers a thrust range of 9,500-12,000 lb.
Engine certification is planned in 2015, says Francois Planaud, Snecma's general manager for commercial aircraft engines.
Snecma will build eight development engines, adds Laurence Finet, Silvercrest general manager. Flight trials will take place on a company Gulfstream G3.
The engine, with a 5.9:1 bypass ratio, will sport a 42.5-in.-dia. fan with 20 wide-chord metallic blades, a high-pressure compressor with four axial blisk stages and a single centrifugal compressor. Silvercrest also will have a single-stage high-pressure turbine, a compact four-stage booster and a four-stage low-pressure turbine.
A high-pressure core demonstrator ran in 2007-08, with full-scale development launched in third-quarter 2010.
On the Longitude, Garmin will provide its G5000 flight deck (already the baseline for the Latitude), with three large touchscreens. It is the largest aircraft application yet for Garmin, as it tries to penetrate the market that has been long-dominated by Honeywell and Rockwell Collins. The G5000 also is being used on the Citation X and Bombardier Learjet 70/75 (see p. 20).
The aircraft will receive a new wing design, with a super-critical airfoil, a straight leading edge with a 30 deg. sweep and small winglets. The modest wing sweep results in a relatively sharp increase in drag above its Mach 0.82 design cruise speed, but that is still 11 kt. faster than Columbus.