PPRuNe Forums - View Single Post - Max motoring or min N3 / N2 for fuel on at start ?
Old 23rd May 2008, 13:14
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lomapaseo
 
Join Date: Mar 2002
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groundfloor
The thing is jets are air cooled so you need to pump air in to cool them - a cold slow start can be very detrimental. Your temp indication might be low but as there is insufficient airflow (low comp rpm) certain components will be cooking.
Thanks for that

I was having trouble getting my head arround the suggestion of increased TIT or EGT with low RPM starts.

What I believe that you are saying is that for a nominal TIT (turbine inlet temp) the actual blade and vane temps may be much hotter due to reduced cooling air flow from the compressor.
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