Flight testing of the US Navy's Boeing T-45 Goshawk jet trainer is planned for May in an effort to eliminate engine surges experienced at high angles of attack.
Windtunnel testing of a model inlet and wing has been conducted at NASA Langley in a bid to isolate the problem, which occurs during air combat manoeuvre training, says Navy programme manager Capt Tim Heely.
Solutions identified include cutting 50mm off the jetpipe, which would reduce thrust slightly, and modifying the inlet and wing, which would be expensive. The alternative is to live with the problem, he says.
Efforts to overcome the surge problem are not fully funded, Heely admits. A programme is under way already to increase the hot-section life of the T-45's Rolls-Royce Turboméca Adour 871 turbofan to the originally specified 1,000h. The hot-end improvement programme is "pretty well funded", he says.
R-R, meanwhile, is trying to interest the Navy in its latest Adour 900, while AlliedSignal is still working to get its F124 engine on to the T-45, but Heely says the issue is "money".
Heely says that the T-45 mishap rate is "very good", but investigation continues into a recent take-off collision thought to have been caused by inadequate directional stability during the take-off roll.
Source: Flight International