Laser9 Posted June 17, 2022 Share Posted June 17, 2022 From what I remember if I tried starting without turning the inverter on the igniters would not be powered and the engines would be flooded with fuel. If I tried restarting without motoring it would not work. Now it seems you don't have to motor them anymore you can just restart. I am remembering wrong or did they change it? Link to comment Share on other sites More sharing options...
jaylw314 Posted June 17, 2022 Share Posted June 17, 2022 (edited) Interesting, nice catch. You can actually go through the start sequence with the inverter and igniters off, then flip on the inverter and it appears to start perfectly fine. Edited June 17, 2022 by jaylw314 Link to comment Share on other sites More sharing options...
zinhawk Posted July 7, 2022 Share Posted July 7, 2022 Hmm, I only dug into engine behavior a couple years ago and as far as I know they always started right up. If they did change it, it was changed to the more correct behavior, with the caveat that you are now inducing a hot start that doesn't seem modeled. Starting without ignitors would create a long tornadoing fuel cloud coming out the tailpipe. Flicking on ignitors would create a giant fireball. Which is funny for YouTube videos followed by shear panic, but the engines would start. The correct procedure after non ignition is motoring for 2 min, wait 5, and check the pipe for pooling and try again. We do this all the time on test cell to prime the fuel system before the first light off. You may be remembering procedures or they used to enforce the procedure with the start sequence. In any case, its correct operation as is besides the lack of explosion. [sIGPIC][/sIGPIC] Ryzen 5 3600 (4.1Ghz), 32 GB DDR4, Sapphire R9 390X Nitro, Fatal1ty B450 K4 TrackIR, Warthog Stick and Throttle, CH Pedals Link to comment Share on other sites More sharing options...
jaylw314 Posted July 7, 2022 Share Posted July 7, 2022 6 hours ago, zinhawk said: Hmm, I only dug into engine behavior a couple years ago and as far as I know they always started right up. If they did change it, it was changed to the more correct behavior, with the caveat that you are now inducing a hot start that doesn't seem modeled. Starting without ignitors would create a long tornadoing fuel cloud coming out the tailpipe. Flicking on ignitors would create a giant fireball. Which is funny for YouTube videos followed by shear panic, but the engines would start. The correct procedure after non ignition is motoring for 2 min, wait 5, and check the pipe for pooling and try again. We do this all the time on test cell to prime the fuel system before the first light off. You may be remembering procedures or they used to enforce the procedure with the start sequence. In any case, its correct operation as is besides the lack of explosion. LOL, that would be a funny YT video I also assumed that the essential AC bus that the igniters are on would be powered by the APU generator, but in DCS it seems to require the inverter switch to be on STBY, regardless of whether the APU generator is running or not. Link to comment Share on other sites More sharing options...
zinhawk Posted July 8, 2022 Share Posted July 8, 2022 (edited) On 7/7/2022 at 4:06 PM, jaylw314 said: LOL, that would be a funny YT video I also assumed that the essential AC bus that the igniters are on would be powered by the APU generator, but in DCS it seems to require the inverter switch to be on STBY, regardless of whether the APU generator is running or not. Ignitor power is routed through the inverter regardless of power source. I'm weak on aircraft E/E, but If memory serves we could run the inverter off the main battery. I only say that because I don't recall needing a power cart for ignitor checks, but I've also done it with which is like listening for a blinker with someone firewalling a CAT 6 ft away. That aspect of no ground power and no APU and still getting inverter may or may not be a booboo. Edit: Verified for sure inverter runs on Main Battery in case there was any lingering doubt. Edited July 9, 2022 by zinhawk 1 [sIGPIC][/sIGPIC] Ryzen 5 3600 (4.1Ghz), 32 GB DDR4, Sapphire R9 390X Nitro, Fatal1ty B450 K4 TrackIR, Warthog Stick and Throttle, CH Pedals Link to comment Share on other sites More sharing options...
jaylw314 Posted July 8, 2022 Share Posted July 8, 2022 1 hour ago, zinhawk said: Ignitor power is routed through the inverter regardless of power source. I'm weak on aircraft E/E, but If memory serves we could run the inverter off the main battery. I only say that because I don't recall needing a power cart for ignitor checks, but I've also done it with which is like listening for a blinker with someone firewalling a CAT 6 ft away. That aspect of no ground power and no APU and still getting inverter may or may not be a booboo. LOL, you're right, I looked at the electrical diagram a little closer, and smack in the middle it says "NOTE" the AC essential bus receives no power from any source when the inverter switch is off. I have to imagine the battery is capable of powering the igniters, otherwise a ground air start wouldn't be possible (not that it is in DCS). Link to comment Share on other sites More sharing options...
Recommended Posts