Cruizzzzer Posted June 18, 2021 Share Posted June 18, 2021 Hey everyone! Does anyone know the max "starter duty cycle" for the ATS? Cannot find any limitations in the manuals... just don't think you can crank it without any limit... Link to comment Share on other sites More sharing options...
Cepheus76 Posted June 18, 2021 Share Posted June 18, 2021 I am not sure, but I think the Hornet uses compressed air supplied by the APU to turn the compressor for engine start, so there shouldn't be a starter cycle limit. Same goes for the ignition circuitry, provided its rated for continous operation. Link to comment Share on other sites More sharing options...
cjladd11 Posted June 18, 2021 Share Posted June 18, 2021 Correct. The ATS (Air Turbine Starter) used compressed air fed off a bleed valve from the APU introduced to it depending on what side motor you want to crank or start. As long as you have 10 percent N2 and 10 oil PSI, those were the start limits, at least on F414GE400s for a Rhino. The air drives the starter which drives the AMAD which then drives the Power Transmission Shaft to start spooling the blades and getting air into the turbines and combustion chamber. At the limits described above (I don’t recall what they were for Charlie’s) you moved the throttles from off to idle and completed the start. The only thing you had to worry about was ATS cautions which has its own EP. You could move the throttles from the lower limit all the way up to when it stabilizes after you hit the crank switch. Would have to get a NFM to get the exact number, high 20s percent for the N2 RPM I think. Sent from my iPhone using Tapatalk Pro 1 Link to comment Share on other sites More sharing options...
VIKBELL Posted June 18, 2021 Share Posted June 18, 2021 Most real life aircraft has a duty cycle 5 minutes on 10 minutes off. There are 2 categories of fighter pilots: those who have performed, and those who someday will perform, a magnificent defensive break turn toward a bug on the canopy. Robert Shaw Link to comment Share on other sites More sharing options...
Mo410 Posted June 19, 2021 Share Posted June 19, 2021 No limit to cranking, just don't engage it above 30% RPM or you risk a shear of the ATS, not sure if this is modeled, unlikely is my guess. Just air until the APU runs out of fuel. 1 Link to comment Share on other sites More sharing options...
Cruizzzzer Posted June 19, 2021 Author Share Posted June 19, 2021 Hey everyone! Thanks for your replies. Sure the ATS takes the bleed air and cranks the ENG through the gear box. But there MUST be a starter limit (time) as you cannot endlessly crank the ENG, though the limit is not the ENG but the ATS. On "mine" it is for example: 2min ... ON and 10sec ... OFF. Anyway... no big deal, just thought anyone knows as NATOPS doesn't give any details. Thanks to all!!! Link to comment Share on other sites More sharing options...
HILOK Posted June 19, 2021 Share Posted June 19, 2021 3 hours ago, Mo410 said: No limit to cranking, just don't engage it above 30% RPM or you risk a shear of the ATS, not sure if this is modeled, unlikely is my guess. Just air until the APU runs out of fuel. just tested it: RPM doesn't go beyond 29%N1 in DCS Link to comment Share on other sites More sharing options...
Cruizzzzer Posted June 19, 2021 Author Share Posted June 19, 2021 39 minutes ago, HILOK said: just tested it: RPM doesn't go beyond 29%N1 in DCS It is meant the other way round: if the ENG runs up but doesn't light up correctly (e.g. hung start) you need to wait for the ENG to spool down below 30% before you reengage the starter Link to comment Share on other sites More sharing options...
mongo52 Posted June 19, 2021 Share Posted June 19, 2021 Been a while but if I remember right I believe ground maintance mode (apu to windmill either eng but not actually start the eng) was limited to 30 mins at a shot. Link to comment Share on other sites More sharing options...
Mo410 Posted June 19, 2021 Share Posted June 19, 2021 8 hours ago, HILOK said: just tested it: RPM doesn't go beyond 29%N1 in DCS More for a hot start, where you go cutoff at day, 45 percent, and since you are required to motor the engine for two mins, you need to wait until it is below 30 percent before engaging the crank switch. Link to comment Share on other sites More sharing options...
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