Toni Carrera Posted July 15, 2013 Share Posted July 15, 2013 Is there some mechanical reason why when I fly inverted for more than about 20 seconds the plane shuts down. Both engines flame out and won't restart. I know it is not common practise to fly in such a manner but I was just curious. IR Toni Carrera (Ice Rhino) ThrustMaster HOTAS Warthog Throttle & A10C Stick, ThrustMaster F/A-18C Stick, ThrustMaster TFRP Pedals, ThrustMaster Cougars x 2, fitted to CubeSim USB Screens, TrackIR 4 Active LED & Cap Reflector, Stream Deck XL Intel® Core™ i7-5820K 12 Core Processor, 32GB RAM, 1 x 500GB SSD, 2 x 256GB SSD, 1 x 1TB SSD 4 x 4TB Western Digital Mechanical. 2 x ASUS GTX 1080's SLI, ASUS 29" Ultrawide flanked by 2 x 22" IPS Monitors Link to comment Share on other sites More sharing options...
Corvus Posted July 15, 2013 Share Posted July 15, 2013 Is there some mechanical reason why when I fly inverted for more than about 20 seconds the plane shuts down. Both engines flame out and won't restart. I know it is not common practise to fly in such a manner but I was just curious. IR From DCS A-10C manual p. 133 "Note: For negative G flight, the A-10C has collector tanks that will supply the engines with sufficient fuel for 10 seconds of operation at MAX power. If you fly at negative G for more than 10 seconds, you risk the engines shutting down due to lack of fuel supply." My YT channel https://www.youtube.com/user/corvuscorp81 Link to comment Share on other sites More sharing options...
Harzach Posted July 15, 2013 Share Posted July 15, 2013 Is there some mechanical reason... Fuel starvation. Link to comment Share on other sites More sharing options...
HugePanic Posted July 15, 2013 Share Posted July 15, 2013 They should restart, but i didn't try it... Link to comment Share on other sites More sharing options...
r813 Posted July 15, 2013 Share Posted July 15, 2013 They do restart. Put the aircraft upright again, then shut off the throttles to the engines. Spool up the APU. Once it is at 100% then move the first throttle to idle and wait for the start up cycle to run through. Then do the same on the other engine. If one engine is still running I think you can use bleed air from it to start the other one but it is a while since I have done this. You won't need the APU for that. Link to comment Share on other sites More sharing options...
311Gryphon Posted July 16, 2013 Share Posted July 16, 2013 They do restart. Put the aircraft upright again, then shut off the throttles to the engines. Spool up the APU. Once it is at 100% then move the first throttle to idle and wait for the start up cycle to run through. Then do the same on the other engine. If one engine is still running I think you can use bleed air from it to start the other one but it is a while since I have done this. You won't need the APU for that. Yeah if you have one running the easiest way (in my opinion) is to go into a dive, turn the Bleed Air switch off, flip the Crossfeed switch to Crossfeed, wait for the ITT to get below 150C, then set both throttles to Max and set the Engine Operate switch of the engine you're trying to light to IGN. Once it's up and running pop it back to NORM and turn the Crossfeed to off and the Bleed Air to on. That one has never failed to work for me even when I haven't done it exactly right. Once I forgot to set my throttle back (I had shut it down to kill the engine for practice) and I ran out of room to dive but the engine did start when I kicked the throttle to Idle. The APU mid-air restart is harder for me to get although I've done it. But you're correct about the single engine and both engines with the APU. http://www.youtube.com/user/311Gryphon i7-8700, 32 GB DDR4 3000, GTX 1080 TI 11GB, 240 GB SSD, 2TB HDD, Dual (sometimes Triple) monitor, TM Warthog HOTAS, Saitek Pro Combat Pedals, TrackIR [sIGPIC][/sIGPIC] Link to comment Share on other sites More sharing options...
PFunk1606688187 Posted July 16, 2013 Share Posted July 16, 2013 I believe for a proper APU start of the engine(s) after a flame out you need to set the Engine Operate Switch for the affected engine to MOTOR. This purges unspent fuel from the engine, and failing to do so could cause the engine to not ignite correctly. Also make sure you actually shut it off behind the Cutoff detent before trying to restart the engine. Switch the Operate Switch from MOTOR to NORM once the engine restarts. Gryphon pretty much has the windmill restart procedure down. Warning: Nothing I say is automatically correct, even if I think it is. Link to comment Share on other sites More sharing options...
311Gryphon Posted July 16, 2013 Share Posted July 16, 2013 I believe for a proper APU start of the engine(s) after a flame out you need to set the Engine Operate Switch for the affected engine to MOTOR. This purges unspent fuel from the engine, and failing to do so could cause the engine to not ignite correctly. Also make sure you actually shut it off behind the Cutoff detent before trying to restart the engine. Switch the Operate Switch from MOTOR to NORM once the engine restarts. Gryphon pretty much has the windmill restart procedure down. I think you are correct about that. I may be mistaken but I think you could have a hot start if you don't motor them. I have to hold my TM Warthog engine op switches to motor them. They won't stay in that position although they will stay in the IGN position. Good point though on the Motor setting and setting the throttles behind the detent. http://www.youtube.com/user/311Gryphon i7-8700, 32 GB DDR4 3000, GTX 1080 TI 11GB, 240 GB SSD, 2TB HDD, Dual (sometimes Triple) monitor, TM Warthog HOTAS, Saitek Pro Combat Pedals, TrackIR [sIGPIC][/sIGPIC] Link to comment Share on other sites More sharing options...
Hamblue Posted July 16, 2013 Share Posted July 16, 2013 . I have to hold my TM Warthog engine op switches to motor them. They won't stay in that position although they will stay in the IGN position. . Mine will stay in motor but have to hold in IGN position, exactly opposite. Asus Sabertooth P67 Motherboard 2600k CPU, 16 gig DDR3, 1600. Samsung 830, 256 gig hard drive, GTX780 Video Card, Warthog Hotas, Razer Mamba mouse. Saitek Combat Rudder Pedals. Trackir 5, Verizon FIOS 25Meg Up/Down Link to comment Share on other sites More sharing options...
311Gryphon Posted July 17, 2013 Share Posted July 17, 2013 Mine will stay in motor but have to hold in IGN position, exactly opposite. Maybe I have that backwards. I'll have to check. http://www.youtube.com/user/311Gryphon i7-8700, 32 GB DDR4 3000, GTX 1080 TI 11GB, 240 GB SSD, 2TB HDD, Dual (sometimes Triple) monitor, TM Warthog HOTAS, Saitek Pro Combat Pedals, TrackIR [sIGPIC][/sIGPIC] Link to comment Share on other sites More sharing options...
PFunk1606688187 Posted July 17, 2013 Share Posted July 17, 2013 From the A-10A Flight Manual Two engine operate switches (figure 1-4), one for each engine, are located on the engine control panel. These switches are placarded ENG OPER Land R, with each switch having three positions placarded IGN, NORM. and MOTOR. The switches are spring-loaded from IGN to NORM positions. The switches must be raised when moving between NORM and MOTOR. Momentarily placing the engine operate switch to IGN will supply ignition to the corresponding engine for 30 seconds regardless of the throttle position or engine core rpm. NORM is used during normal engine operation and for engine starting. MOTOR is used for air-purging of excessive fuel, cooling the engine or manual starting. When the switch is moved to MOTOR the following actions are accomplished, provided electrical power and an air source are available: • ATS valve opens causing the ENG START CYCLE light to come on • ECS shutoff valve closes • Both engine bleed air shutoff valves open. NOTE • The throttle must be in OFF or IDLE in order to motor the engine. The engine operate switches are powered by the DC essential bus. Seems you don't need to hold the IGN switch. Warning: Nothing I say is automatically correct, even if I think it is. Link to comment Share on other sites More sharing options...
Recommended Posts