CL 65 Eng Fuel question

[Ebnyflyer]

My guess, thanks

Thanks guys and girls for your responds. The fuel system pumps consist of a jet pump (pri), AC pump (sec), and engine driven pump. My feeling/guess was the engines would continue to run below a max altitude. The EDP by nature should be able to pull fuel out of the fuel lines. I also suspect the eng driven fuel pumps are altitude rated in the event of a motive flow pump failure. While I understand how motive flow (jet pump) works, its purposes in life is just to provide positive fuel VOLUME in the fuel lines. Head pressure to the EDP is the result. The EDP is what regulates fuel pressure to the FCU and VSA.
I knew this was the right forum to ask.
Thanks again and for your help.
LL

 

[Timebuilder]

Great info.

Does anyone know of any free, online info about topics like this: system diagrams, theory of operation, checklists, flows, callouts, etc?

Nothing proprietary, just general stuff?

Thanks. This was interesting.

 

[gump88]

The engines would continue to run based on your scenario. One question: how do you "lose" a motive flow pump. It is simply a piece of steal shaped like a venturi.

If the high pressure engine driven fuel pump failed then the associated engine would quit!

gump

 

[JETBOUND]

I agree with everyone that this situation, should it occur, would be beyond rare. However, I have heard of a situation in which the motive flow(Jet Pump, Venturi Pump, whatever you want to call them) has failed. Again, very rare! In this case(don't remember the Aircraft), someone had dropped a piece of cloth, towel or something in the tank. The fuel somehow separated the threads of the cloth and it ended up clogging the motive flow.

Should probably be in the General posts, but good Thread!

 

[Slim]

Here are some numbers which may explain things better...

The engine driven fuel pump delivers fuel at 800+ psi. The electric boost pumps go to standby when the engines are operating. They come on line when the fuel line pressure drops below 9 psi. As you can see, there's no way the electric boost pumps can sustain engine operation when the engine driven pump fails.

Fly safe!

Slim