Capt1124 said:
My first job on a Westwind was as an SIC on a II. It had the digital ITT readout that has the "H" light up when the temp reaches 885.
Because of this, the PICs I flew with believed as long as the "H" wasn't lit up, it was OK. (The climb limit of 870 and the cruise limit of 849 often ignored.)
One day the "Fuel Controller Manual Mode" light comes on the left engine and I get the checklist. The PIC saw that it was over temping and shut it down, but it was too late. We landed and there was a stream of metal particles coming out the tailpipe.
Another Westwind I flew had minor fuel controller malfunctions (going to manual mode) but nothing particularly disturbing.
I was told once by an old hand that the reason the MSP program came about was the high unreliability of these engines when they first came out. Duncan told me these engines tend to be very beat up when coming off Westwinds and Hawkers, which I suspect is from pilots running them hot to try to make the plane go faster.
In my opinion the one thing you must do with these engines is always carefully observe the temp limits. That's ture of all engines but my impression is these are more sensitive than most.
870 degrees in Simuflite's recommended climb setting, as to not over-speed the N1s.
you can run the TFE731-3-1Gs on the Westwind at 885 degrees for 30 minutes during a single cycle. You can run them at 907 degrees for 5 minutes. I think 907 is only possible with EECs, I believe the DEECs will MAX out on the N1s first.
Anyway, Simuflite recommends running the power at 870 during the climb up to FL300, then allowing the ITTs to creep up to 885 and only adjusting throttle position as to not overspeed the N1s.
Our department proceedure is the above, we allow the ITT to creep up to 885 while not exceeding 101.4% N1.
While we run our engines hard in the climb, they were designed for that, once we reach the 30 minute mark, we pull the power back to 849, then look into the simuflite book to get a fan speed for our flight level/weight/temp for a constant mach cruise.
Sometimes we might be at 849 on the ITTs for an hour until we burn off enough fuel to start pulling the power back for a .72 cruise. (Example of a West coast trip, and we fly 4 hours 40 minutes and land with 2200 Lbs, no AUX tank, WW1)