to strawberry boy and NSEU
to my favorite strawberry type
if the APU is delivering "plenty of ducktpressure" you dont have to perform a ground air start. its performed when the APU does´nt deliver pressure
to NSEU
as we know the Demand pumps are AUX/ AUTO for engine start. 1,2 and 3 are AUTO and 4 is AUX
you asked why do i run the Demandpumps.its MAGIC! because the selector is in AUTO. It stands for AUTOMATIC
.they run by them self. the conditions for demand pumps to jump in are
Respective Engine Driven Pump output pressure is low or respective Fuel Control Switch in CUTOFF
when hot and high and especially on ground air you are starting one engine at a time, its usually 2 or 3. ALL conditions are met for demand pump auto function. the number 1 demand pump runs magically by it self. this reduces "ductpressure"
unless you turn number 1 demand pump selector to OFF instead of AUTO.
try it next time. if the APU is running normally, maybe the rise in PSI is not so significant, but if you are on a cart you will see the difference.
dont know if the FS2000 support this feature for the simmers
happy enginestarts
Lars