Snecma is halfway through a four-month engine core test of its 9,500-12,000lb thrust (42-53kN) Silvercrest engine, a powerplant targeting next generation large-cabin business jets and 40- to 60-passenger regional jets.
The engine maker is marketing the engine to as many as six different airframers, with Embraer and possibly Bombardier the leading candidates.
The company between 30 November and 29 January had completed 35h of combustion tests on the internally funded $100 million research and development effort and had achieved engine speeds as high as 19,800rpm, representing 85% of take-off power.
The engine is situated in test chamber that supplies pressurised intake air at various temperatures and pressures to simulate a complete turbofan´s low-pressure fan section at different altitudes. Engineers during the tests are monitoring 660 real-time parameters. Laurence Finet, general manager for the Silvercrest programme, says the mechanical behaviour and performance of the engine to date have been "excellent". Tests in February and March will include take-off power, exhaust gas analysis, transient accelerations, bleed scheduling and combustion characteristics.
The Silvercrest core features a Turbomeca-designed impellor - a design choice the company says replaces two compressor stages - followed by a four-stage axial-flow compressor and a single-stage high-pressure turbine downstream of the Avio-provided combustor. Avio makes the gear boxes and combustor modules for Snecma´s SaM146 engine, a 50/50 joint venture with Saturn NPO. By choosing an impellor, Snecma has limited the future growth of the engine since thrust levels greater than 12,000lb typically require axial flow compressors. After core tests are complete in March, Finet says engineers will "pre-design" a full engine.
Sizing, however, should be appropriate for some 2,600 new large-cabin business jets that Snecma predicts will require 9,500-12,000lb thrust engines through 2017, as well as for a new generation of smaller regional jets that could be needed in the latter half of the next decade.
The company plans to offer a complete package, including engine, nacelle, thrust reverser and aftermarket support. Snecma officials last year said the Silvercrest would have on-wing times in the neighbourhood of 10,000h, two- to three-times the typical life of similar business jet engines.
Loic Nicolas, Snecma manager for the business aviation market, says all six major business aviation airframers are working on projects that could use such an engine. Although Cessna´s new large cabin Citation and Bombardier´s new Learjet 85 will require lower-thrust powerplants, both could become customers in the near future with larger aircraft.
Bombardier is said to be working on a large cabin concept dubbed M127, and Cessna will likely expand the Citation line upward over time. Perhaps closest to making a decision will be Embraer with a launch decision for the midsize or mid-light concept jets it revealed last year. "We are exchanging a lot of data with (Embraer)," says Nicolas.