Fuel shut-off vs cut-off

[seikdel]

I'm not a real pilot, nor am I a flight engineer, but I am trying to understand a bit more about how the innards of the bird work.

My understanding is that the fuel shut-off is the valve by the tank that determines whether any fuel gets to the engine at all. What's the cut-off do?

 

And along the same lines, I accidentally killed my shut-off for my right engine in flight (whoops, wrong macro) and could NOT get the thing restarted. Every time I tried to start or crank, the temperature would raise a little bit but the engine RPM wouldn't budge. Did I do something major to the engine by closing the shut-off valve instead of the cut-off?

[BBQ]

Nor am I a real pilot--but I think that the cut-off (red levers by collective) are the valves that open to start the "light off". The engines will ramp up to 20% or so, but will not go further as their is no "ignition" yet. The bleed air from the APU is getting it going up to that point, is how I understand it. I'm about as in the dark as you, though. I know one thing--NOTHING is going to happen if the "shut-off" valves aren't open. There must be some kind of hard interlock between shut-off valves and start sequence.

[sobek]

And along the same lines, I accidentally killed my shut-off for my right engine in flight (whoops, wrong macro) and could NOT get the thing restarted. Every time I tried to start or crank, the temperature would raise a little bit but the engine RPM wouldn't budge. Did I do something major to the engine by closing the shut-off valve instead of the cut-off?

 

IIRC there is still a little 'bug' present, namely, if the engine start is engaged with the turbine at standstill and the starter air turbine still running down from the previous start, the starter clutch will be subjected to too much torque when engaging (because of all the momentum that the air starter has) and will fail, resulting in any subsequent starts not being possible. The behaviour is actually real, the only problem is that the rundown time for the air starter was modeled *way* too long, so if you try to start and shutdown and start again without a good few minutes in between, the clutch will fail inadvertently.

[Kite]

This is also my doubt. Could it be that one gave power supply to the pumps and the red levers open the valves? Maybe..

[AlphaOneSix]

There are fuel shutoff valves that allow or prevent fuel from flowing to the engine. They are located away from the engine. These valves are operated by the fuel shutoff switches on the right side panel.

 

The fuel cutoff levers attach to the fuel controls on the engines themselves, they are not electric valves, but are mechanically operated valves that are mounted on the engine itself.

 

Even with the cutoff valves shut but with the shutoff valves open, fuel will get to the engine driven fuel pump, the low pressure fuel filter, and enter into the fuel control. However, for fuel to be delivered to the fuel delivery manifolds, the cutoff valves must be open.

 

With the shutoff valves closed, fuel will be stopped several feet away from the engine.

 

The fuel shutoff valves are intended to be used as fire shutoff valves to prevent fuel flow from getting near the engine in the event of engine damage and/or fire.

 

The cut off levers are intended to allow or prevent fuel flow through the engine fuel control for normal starting and shutdown procedures.

[Kite]

I was looking for this . Thanks

[awdrgyjo]

Hi, i'm fairly new to this forum but have been lurking for a while, this is precisely the reason I decided to join, people with a wealth off information, and ready to impart this in so much detail, also the more posts I read, confirms how detailed the sim really is.