Author Topic: Hurri I and negative G engine shotdown (Read 661 times)

DiabloTX · « **Reply #15 on:** August 31, 2003, 10:24:29 PM »

Errrrgh...no, my question was in AH if you go neg g's too long does the engine cut require a restart manually? In my experience the engine always came back after a pull up but have not seen what it does after sustained neg g's.

DiabloTX · « **Reply #16 on:** August 31, 2003, 10:25:01 PM »

Errrrgh...no, my question was in AH if you go neg g's too long does the engine cut require a restart manually? In my experience the engine always came back after a pull up but have not seen what it does after sustained neg g's.

DiabloTX · « **Reply #17 on:** August 31, 2003, 10:26:14 PM »

Wow...how did that happen? Sorry.

Xjazz · « **Reply #18 on:** September 01, 2003, 01:16:29 AM »

Quote

Originally posted by DiabloTX
Errrrgh...no, my question was in AH if you go neg g's too long does the engine cut require a restart manually? In my experience the engine always came back after a pull up but have not seen what it does after sustained neg g's.

Hi,

I just tested this sustain neg G condition.

I climb to the 20k alt and start left hand INVERT dive turn. I glide down 160-200mph(IAS) and I could keep prety constant -1.5G. Alter 1+ minute I rollout from invert dive turn at 1k and engine start it self without problem.

Concerning my experience it has take only ~10sec neg/zero G for totally engine shotdown... As I say before, this has occure only few times.

Maybe lateral forces has something to do with this. Sudden lateral transition from -G to the +G flooding the left/right side carbs?

I dont say this is a bug or any problem. Its just cause those "Whatta Heck?!" moments and paniced fuel & damage checks.

Hades55 · « **Reply #19 on:** September 01, 2003, 02:25:03 AM »

real hurry & first spit pilots was not doing neg G.
They was rolling and diving with +G.Inverted.

MiloMorai · « **Reply #20 on:** September 01, 2003, 06:06:14 AM »

Xjazz,

the Merlin was only fitted with 1 carb and that was before the blower.

Xjazz · « **Reply #21 on:** September 01, 2003, 06:26:22 AM »

Quote

Originally posted by MiloMorai
Xjazz,

the Merlin was only fitted with 1 carb and that was before the blower.

Thanks Milo.

I was just guesing.

loser · « **Reply #22 on:** September 01, 2003, 11:52:12 AM »

Perhaps the engine is not really shutting down. It may be that the time the engine takes to get back running is proportional to the time or severity of the negative Gs you are pulling.

Im just thinking of when pulling extreme and extended positve Gs, you black out for longer. Sometimes I have had a completely black screen for ten seconds! (no my pilot wasnt wounded. I'll point out that this has happened after i have released all pressure on the stick.

So maybe this egine cut out is the same thing. Next time it happens (when your engine seems totally dead,) just try waiting. Worse thing that could happen is you hit the ground and you have to re-up.

And no use trying to recreate this problem you experience. You know bugs never occur when you want them too.