fuel pumps always working

[DarkWanderer]

Oh and btw, most modern fuel systems and engines will "gravity feed" the fuel isn't "sucked" out as such. The fuel tanks are also pressurised by conditioned bleed air from the engines which aids the process. Obviously, any hard manoevering may cause a flameout, especially at low fuel states.

It's a chopper, not a B747. Engines are above the hull.

And IIUC there's no tank pressurizing either.

Edited July 16, 2009 by DarkWanderer

[Druid_]

ok so how exactly is the fuel sucked upwards to the engines? It has a seperate mechanical pump capable of pulling the required fuel from the tanks?

 

Tank pressurising helps stop fuel pump cavitation and helps regulate the flow of fuel, but for a low altitude heli you could be right. If Nitrogen is used in the tank however, pressurisation is normally required.

[DarkWanderer]

ok so how exactly is the fuel sucked upwards to the engines? It has a seperate mechanical pump capable of pulling the required fuel from the tanks?

http://www.digitalcombatsimulator.com/index.php?lang=en&end_pos=1638

[Druid_]

That diagram doesn't help I'm afraid, although it does answer the fuel crossfeed question. Also looked at the engine diagram but again not enough detail.

A detailed diag of the pneumatic/air con system would've been nice, then we might have had an answer to the fuel tank pressurisation question.

[AlphaOneSix]

The engines have engine-driven fuel pumps. Obviously, they don't work very well until the engine is spooled up, but once the engines are operating normally, the pumps are capable of sucking fuel out of the tanks without the help of the tank pumps unless you get up to high altitude.

 

The crossfeed is just a valve, it allows either tank to feed either engine. With the crossfeed closed, the forward tank fuels the left engine and the aft tank fuels the right engine. With the valve open, both tanks feed both engines.

 

Some helicopters have nitrogen inerting units that put nitrogen into the fuel tanks as fuel is removed, but many use simple vents that allow outside air to replace used fuel. I do not know for sure what the Ka-50 uses, either would not surprise me.

[leafer]

So...is it a bug then?