The RR Spey had a "Start" and "Run" position on the Fuel Cock. Below a certain temp. the start position would be used initially to provide more fuel during start, then the lever was moved to Run. Above this temp the lever would be put straight to Run.
It may have been 10 C but I'm not sure. It's been about 30 years since I last ran a Spey.
Also as 4Screwaircrew says, the RR Dart required trim setting, but I think we used to set 75% for start and then trim back to control the temp during the start.
After start the trim was set for take off using a small rotary slide rule (called the "Trim Computer") to calculate the correct figure using temp. and pressure alt.
Last edited by dixi188; 30th Apr 2017 at 07:48.
Reason: More.