CSK
Does that mean that if there is no N2 rotation by the time of 30 sec I need to abort?
Without knowing your engine type I would have aborted the start long before 30secs. If no N2 either indication fault, starter valve not opened or starter drive has sheared.
Engines that I am familiar with would have after start selection, 1-2 secs starter valve OPEN indication then N2 indication.
Further, the time during starter selection is recorded primarily for starter motor duration limitation for the required amount of cooling before next start.
Another time that is noted will be the 'fuel ON time' and if more than say 20-30secs abort the start as engine has not lit.
Maybe ignitor fault, on side selection or fuel fault. After engine has run down the second start would utilise ign BOTH for the second attemp.
maintenance technician uses the starter for dry motoring
and the pilot when a wet start has occurred, to clean the engine of unburnt fuel before second attemp, also to cool the engine down prior to fuel ON if say engine EGT greater than 100'C or what ever your engine requires after a short hot transit.
A typical Air Turbine Starter duration would be
3mins ops then 1min cooling
3mins ops then 1min cooling
3mins ops then 30mins cooling for example
or
5mins ops then 30mins cooling possibly used during tail pipe fire or other emergency.
Clearly a good normal start would be completed well before the 3mins applied.
TW