Production of AlliedSignal's new TFE731-20/40/60 turbofan family is expected to grow to more than 200 engines in 1998 on the back of increased business-aircraft sales, says the company.
The increase follows the entry into service of the TFE731-60 on the Dassault Falcon 900EX and the -40 on the Falcon 50EX and the Galaxy Aerospace Astra SPX. Production rates are also set to rise on the TFE731-20 line to coincide with the anticipated certification and entry into service of the Bombardier Lear 45.
Up to 60 engines will be delivered from the Phoenix, Arizona, production line this year with "between 175 and 225" due for delivery in 1998. Meanwhile, production of TFE731-5Bs for the Falcon 900B and Raytheon Hawker 800XP, -4s for the Cessna Citation VII and -2s for the Learjet 31 continues.
Despite the surge in activity, AlliedSignal says that the numbers will not match the records set in 1981, when around 650 -2, -3 and -5 engines were produced.
The in-service engines have amassed around 14,000 flight hours, says TFE731-20/40/60 programme manager Brian Sill. Test hours on the family, including runs of the -20 on the company's Boeing 720 testbed, increase the total by a further 5,000h. An early cold-soak starting problem on the -60, now powering 13 Falcon 900EXs, has been solved with revised engine-control software, says the company. A fuel-pump problem which emerged on the -40 has also been resolved, it adds.
Impending developments for the -60 engine include the extension of inspection intervals beyond the 2,500h hot section and 5,000h core limits set at introduction. Data are now being collected from in-service engines, which are fitted with an engine-condition, trend- monitoring system as part of the full-authority digital engine-controls. "We hope to be able to set revised inspection intervals within a short period of time using this data," says AlliedSignal, which is thought to have set goals of 3,000h and 6,000h, respectively.
Source: Flight International
