Plans to transfer assembly of Rolls-Royce Turboméca Adour 871 (F405) engines to R-R's US subsidiary Allison Engine have been suspended after the US Navy killed the effort by calling it "unnecessarily risky".

The decision comes as a blow to Allison, which has been working on the transfer plan since October 1996. The transfer was conceived as part of efforts by R-R to bolster the US-based element of the programme following intense pressure from AlliedSignal to displace the engine on the Boeing (formerly McDonnell Douglas) T-45A Goshawk with its F124 turbofan.

Allison and R-R say that they "-agreed to cease all F405 transition activity" after receiving a USN position letter on conversion of the F405 contracts. In a statement they say: "The letter effectively denies any transfer of the F405 in the short term by listing 20 preconditions that must be satisfied prior to the Navy programme manager requesting a Federal Acquisition Regulation waiver for conversion. Adherence to the preconditions would have delayed F405 transition at least a year."

Although details of the specific preconsiderations were not given, they are understood to involve the setting up of a more complex and vigorously scrutinised transfer process. Allison also adds that "-Navy personnel feel that R-R Military Aero Engines has done a good job in supporting the programme, and viewed the risk associated with moving the programme, albeit small, as unnecessary. The Allison F405 team is being broken up and personnel assigned to other programmes".

The plans to transfer engine assembly were well advanced when the scheme was torpedoed by the USN. Assembly of the first engine, the 112th F405 for the T-45 programme, was to begin in mid-October, with its first run due in November. After testing, stripping for inspection and verification, the engine was due to be delivered to the T-45 St Louis, Missouri, assembly line by April 1998.

Source: Flight International