Guy Norris/CINCINATTI
CFM International is in negotiations with prospective launch customers for the CFM56-3 core upgrade and could launch it within 90 days, says CFMI engineering vice president Bill Clapper.
The upgrade combines the three-dimensional (3-D) aerodynamically designed core of the -7B engine developed for the Next Generation 737, with the original low-pressure system of the 737 "Classic" -3 engine. "When you do that you get a reduction in EGT [exhaust gas temperature] of 15íC and a 1% improvement in sfc [specific fuel consumption]," says Clapper, adding that the upgrade is potentially applicable for around 1,000 aircraft.
The upgrade also provides longer life on wing, and reduced maintenance costs, Clapper says, adding that the design has been finalised following more than 100h of operability tests.
The company is also working on an extensive upgrade package for the CFM56-5A/5B engines powering the Airbus A320/A321. The upgrade includes a more durable high-pressure turbine (HPT) blade, coated with a more resistant platinum aluminide layer, which is expected to tackle oxidation issues on the current design, and is due to be available in the second quarter of 2002.
Also being tested is a noise reduction programme for the-5A/5B aimed at bringing the engines into full compliance with likely Stage IV standards. The package includes the chevron nozzles developed in the Tech56 programme, additional noise treatment in the fan duct lining and modifications to the outlet guide vanes behind the fan. The programme, being developed with Airbus, is scheduled to move to full-up engine tests "towards the end of the year". The full kit, to be available in 2003, will be for retrofit and new-build engines.
Meanwhile, the first of four test engines in the CFM56-5C/P upgrade for the A340 Enhanced is scheduled to run in November, with engine certification expected to coincide with first flight of the improved A340 variant in October 2002. Aircraft certification is due around April 2003. The package incorporates the 3D core of the-5B/P and -7B engines with the larger fan and low pressure system of the -5C4, as well as the new HPT blade design and a new LPT stage one nozzle.
The package, which will also be available as an upgrade kit from the fourth quarter of 2003, is expected to improve the -5C4 in-flight shut down average, reduce sfc, EGT and maintenance costs.
Source: Flight International
