Miscellaneous
Miscellaneous
When to shut down engine?
Before you decide to shut down engine pay special attention to engine and other systems associated to concerned engine. Based on that make a decision if and when to shut down the respected engine. When you are hit and get Master caution warning light open the BIT page on your MDI and check what systems have been damaged.
Here are the systems you must pay a special attention to:
- L/R BLEED AIR
- L/R OIL PRESS
- L/R FUEL PUMP
When you're done whit that open the ENG page on your MDI and look for following engine data:
- EGT: When you get BLEED AIR warning monitor closely your EGT (Exhaust Gas Temperature) in degrees Celsius. Maximum normal (at Max power-100%AB) temp. For engine is 930 +/- 10 C . When/if your EGT is starting to rise above that the things are staring to geting Hot. When the EGT reaches the 1400 C shut down the respective engine. If you decide to still run that engine you're risking of checking fire. That will occur when your EGT temp reaches 1450-1500 C when you reach that temp, you have around 5-60sec before FIRE warning accuser and you'll have to activate the fire extinguisher.
- OIL PRESS: When you get OIL PRESS warning monitor closely your OIL PRESS in psi. Maximum normal (at Max power-100%AB) psi for engine is 150 psi. However, when getting OIL PRESS warning (that means your engine is loosing oil pressure) your main concern is not to drop below the minimum oil pressure and that is 35-40 psi. When the psi reaches the 40 shut down the respective engine. If you decide to still run that engine the temp of the engine will rapidly increase and you're risking of catching fire. That will occur when your EGT temp reaches 1450-1500 C when you reach that temp, you have around 5-60sec before FIRE warning accuser and you'll have to activate the fire extinguisher.
When you get FUEL PUMP warning you are (engines) really not in any danger. However, if you get both pumps warning drop bellow 30K baro and don't use AB or you are risking of flaming out your engines.
Shutting down engine before it catches fire is better choice than using the fire extinguisher when on fire because once you use extinguisher you can't use it again. There are no guaranties that the fire will be extinguished and then you are in big dudu. Also you can't restart engine once the extinguisher has been used. However, if you shut down the engine before it reaches 1450 C you have a good chance to restart the engine (just live it some time to cool of - around 5min will do - to cca. 1000 C ? that is if your oil pressure is OK.
Blitz:
Here is one little anecdote from one of my "Near Fire" experiences.
I sustained some damage on one of my sorties, nothing big at the start but when I was around 50nm from Mother got a L and R BLEED AIR warning. I immediately checked the BIT and ENG MDI's and found out that other engine stats were OK other than getting hot. Then I shut down L Eng. immediately and run on 70% R engine. Checked the fuel state, jettisoned all stores and called for emergency landing, AC diverted me to AB located 110nm from me so I knew my only chance is to land on Carrier.
When my R Eng. reached the 1400 C ? I restored the L engine and shut down the R engine. I repeated this procedure 2 times. 10nm from Mother I got a OIL PRESS warning on the R engine that I've joust restarted so I had to reengage L Eng. Now I was running on bought engines that were getting hot weary quickly (especially R Eng. Due to low pressure). My plan was to gain as much of air speed and altitude as I could before I shut down R Eng. Around 5nm from carrier my R Eng. got on fire before I could shut it down so I had to use extinguisher. I was at 6K alt and around 200 KTS whit single engine, which was getting in to dangerous Fire temp zone rapidly. Around 2.5 nm from mother the EGT reached 1500 C ? and I knew I don't have much time left. I put the power to idle and glided to carrier. My speed decreased fast my glideslope was getting dangerously low and I risked a ramp strike so I had to apply some power to correct AoA and VC prior touchdown. I knew it was a matter of seconds before my engine catches fire. I just hoped not before I trapped. I trapped a 2nd wire successfully and shut down the engine immediately.
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