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FDX016 - Nick

Question regarding the Spar and Engine fuel valves

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Hi All,

 

Earlier today I was climbing out of Memphis in the NGX and was recording my takeoff with FSRecorder. To end the recording, I have to hit ESC... Well, my two engine master cutoff switch hot keys are right below the ESC key and I bet both of them on accident. I quickly hit my two engine master idle hot keys and the flight resumed normally. I must have hit them quick enough as not to totally interrupt the flow of fuel to the engines.

 

Ok, now for the part I'm wondering about- why did the left and right engine/spar valve closed lights stay on for the entire remainder of the flight? I figured they only come on when the two master switches are in cutoff, but why would they stay on in this case despite the master switches being in idle?

 

Thanks in advanced!


Thanks!
Nick Crate
Chief Executive Officer
FedEx Virtual Air Cargo

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I'm guessing it is a error in the simulation. If those valves were actually closed the engine would not be running. I have noticed when I move the start levers to cutoff there is a delay before the engines actually begin to spool down in the NGX. Moving them back and forth so quickly you may have confused the simulation. In the real plane the engines shut down pretty much instantaniously after moving the start levers to cutoff.


Tom Landry

 

PMDG_NGX_Tech_Team.jpg

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The light is bright? If yes it could explain that the valve is neither open or closed, in transit or it disagrees the start lever position.

However, if no failures are present the valve must be opened (light off) when engine is running.

There are 2 valves feeding the engines, the spar valve is the one on the aircraft, the other (HPSOV) is on the engine. Both are needed open to let the fuel go to the fuel injectors.

The delay in shut down is because during valve closing and after it the remaining fuel is still burned.


Regards

Andrea Daviero

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I believe ( and I may be wrong ) I read somewhere a while back that it's an FSX limitation/problem. Add it to the list...


Dave Wegner

 

- Don't be afraid of common sense or the search function.

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I will try but I remember that all lights are working correctly on the NGX, I will recreate the replay situation.


Regards

Andrea Daviero

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They are working exactly as they should- except in this one case. Accidental down-up of the master levers for engine 1/2 while in-flight.

 

I've also had a few pilots report to me about having one of those lights on for the whole flight. It's very odd... And they had no failures active.


Thanks!
Nick Crate
Chief Executive Officer
FedEx Virtual Air Cargo

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I noticed it to, if you cycle the fuel cutoff levers quickly the ENG VALVE and SPAR VALVE closed light illuminates brightly telling the flight crew there is a disagree between the fuel cutoff levers and the actual position of the valves,

 

When you switch the fuel cutoff levers from cutoff to Idle the valve indicator lights goes from DIM to BRIGHT and than to OFF.

 

When these indicator light's are in DIM the valves are closed.

When these indicator lights are BRIGHT the valves are in transit or there is disagree between the valve position and the cutoff lever, and when the indicator lights are OFF the valves are open.

 

In this case where cycling the lever quickly, the valves are not making a (simulated) full cycle and stops half way. to correct this is to switch the fuel cutoff levers to IDLE or CUTOFF to let the valve fully close or open and than switch the levers back to the original position in this case is to restart the engine's.


Mark Scheerman

 

Boeing 737-6/7/8/900 Ground Engineer

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