Yesterday I flew out of Edmonton, and the temp was -25 C.  Both engines took multiple times to fire up, running normal starting procedure. They would start to spin up and just die.  I read a tip this morning from another Q400 pilot on Facebook Q400 group, and he suggested I run the deice program in the FMS. I did that this morning and despite the fact that it was even colder, -29C, after running deice, both engines easily started. 

i think part of the SOP is also that you have the engine intake bypass switches set to open in cold conditions, i forget what the limiting temp is tho, below 5C or something. i believe the FMC command simulates manually clearing snow and ice out of the intakes.

..hmm here's a thread on their forum about it here: http://majesticsoftware.com/forums/discussion/2640/cold-start-procedure-cold-weather-scenario-

cheers!,-andy crosby

 

I'm blown away that this is modeled in sim. A brilliant piece of work indeed