Fuel tank empty

[X_legio]

Hi there, I was in mission and suddenly the ka tell me that the rear fuel tank is almost empty, I have a look and ok the front is still with a lot of fuel, after a while the engine n2 stops for lack of fuel and I have to do a rtb with one engine running. During the flight back I have seen that all the switch for the aft and front fuel tank was on. Any guess ?

 

[razo+r]

Did you get shot?

 

[X_legio]

Nope 100 sure 

[Flappie]

Next time it happens to you, please save a track and attach it here.

[X_legio]

ok, How I can do it ? 

There is nothing with the crossfeed valve ? 

 

Edited November 25, 2021 by X_legio

[Volk.]

The one fuel tank takes 705kg fuel, and the other 745kg. So the one tank will likely always run out before the other.

The cross-feed ("x feed" I think it's called, next to APU fuel) allows both tanks to feed both engines. So if you're running low fuel, switching that on prevents one engine dying earlier. No idea if that actually lets you keep flying longer, as you're powering both engines, but at least you still have the lift you're expecting.

[Flappie]

1 hour ago, X_legio said:

ok, How I can do it ?

To save a track when playing a single player mission, exit the mission and click the "Save Track" button.

When playing a multi player mission, tracks are automatically saved in "Saved Games/DCS.../Tracks/Multiplayer".

[Rongor]

Multi-engined helicopters are often equipped with different sizes of feeder tanks.

This is a kind of built-in life insurance for the most careless of pilots, who failed to manage their fuel correctly and eventually are even up to ignore the fuel warnings. The idea is to have the crew land within a specific amount of minutes after the low fuel warning (as will be defined in the checklist/AOM). If the crew still carries on, one tank will empty before the other, so the shutting down of one engine will be your last and final warning.

The first engine shutting down would normally be the left engine (number 1) with the Blackshark, as it is fed from the front fuel tank, which has a capacity of 705 kg. The rear tank bears up to 745 kg, so you will have around 40 kg left on the right engine (number2) to bring the helo to an instant but safe landing.

If the rear tank is empty first while the front is not, something has gone wrong. The applicable emergency action would be to open the crossfeed valve to keep both engines supplied from the front tank and keep an eye on the fuel meter to verify front tank fuel level isn't suddenly dropping as well. Consumption from front tank will increase now of course.

Edited November 25, 2021 by Rongor
I like editing stuff

[Fastbreak]

What might have happened: You have not turned the APU off after starting the engines or you have had the APU running very long before take off, so that during flight the Rear Tank pumped dry before the Forward Tank.
The APU also gets its fuel from the Rear Tank, which again feeds the right engine (Engine 2) with Cross-feed valve closed.

[X_legio]

I can't replicate the issue so probably some peones with a small firearms (ak) hit my Ka making an hole into the  rear fuel tank. For sure was nothing big because around wasn't nothing so dangerous...

Thank you Rongor for the explanation... 

[Volk.]

The tanks are self-sealing, so small arms fire is maybe unlikely to cause a significant leak.

Also not sure if I've seen leaks in the Shark's fuel, rather than just death.

[X_legio]

Ok so we have a mistery here.... The only thing I know for sure are that the aft fuel tank get dry and the engine 2 shut down after the ekran alert. On the front fuel tank was enough to come back ( if I remember 500kg).

[Rongor]

2 hours ago, Fastbreak said:

What might have happened: You have not turned the APU off after starting the engines or you have had the APU running very long before take off, so that during flight the Rear Tank pumped dry before the Forward Tank.
The APU also gets its fuel from the Rear Tank, which again feeds the right engine (Engine 2) with Cross-feed valve closed.

interesting point. Something to be tested.

[randomTOTEN]

5 hours ago, X_legio said:

On the front fuel tank was enough to come back ( if I remember 500kg).

That tells me you had a fuel leak. I like the APU idea too. And I have actually experienced a fuel leak in the Hokum so I know that's modeled.