Releasing drop tanks

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gulredrel
Posts: 6
Joined: Tue Jan 08, 2013 12:46 am
Location: Germany
Releasing drop tanks

Post by gulredrel » Thu Jun 26, 2014 7:10 am

Hello,

yesterday I tried F-86 with drop tanks again.
Full internal fuel + drop tanks.

Tank selector set to outboard and jett. position. Fuel was used from the external tanks.

At altitude with the drop tanks not empty I decided to get rid of that external ballast and drag and hit the tank jettison button.
After that, the engine quit. Internal fuel was still full. Could do an air start of the engine.

So what is the correct sequence to drop the external tanks
a) if still fuel is in there
b) if empty

Thanks
Jens

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Releasing drop tanks

Post by JonathanBleeker » Thu Jun 26, 2014 8:02 am

Gee....been a while. I cant recall exactly. It shouldn't happen since the F-86 is supposed to run off the feed tank all the time and only transfer fuel from the other tanks to the feed tank. For now I would suggest changing the fuel selector to a internal tank until I can look at this.

gulredrel
Posts: 6
Joined: Tue Jan 08, 2013 12:46 am
Location: Germany
Re: Releasing drop tanks

Post by gulredrel » Thu Jun 26, 2014 9:26 am

Okay, I'll try setting the selector knob to other than external tanks and thereafter hit the jettison button.

Could anyone else here try this?

edit: Did a new flight. After all the fuel in the droptank was used and the fuel totalizer counted back, indicating usage of internal fuel. I could release the tanks without engine shutdown. But releasing drop tanks half full the flight before resulted in engine shutdown in flight.

Selector knob position all other than "all tanks off" leads to usage of external fuel, even there are no inboard tanks installed. But that would only be the full perfectionism ;)

Ramrod
Posts: 1
Joined: Tue Jun 18, 2013 4:12 pm
Re: Releasing drop tanks

Post by Ramrod » Sun Jul 27, 2014 1:59 am

I've had my engine quit on me after jettisoning (empty) external tanks, to switch to full internals. This has only happened to me once and I sort of figured it might be because I left my engine filter screen switch in the EXTEND position; though I'm not positive if that was the reason.
Hasn't happened to me since that one time. But, to note, the manual does state on page 18 that an engine failure is possible if the Screen Switch is left in the EXTEND position during flight.

Monterey56
Posts: 12
Joined: Wed Jan 20, 2021 5:11 pm
Re: Releasing drop tanks

Post by Monterey56 » Tue Mar 02, 2021 1:01 am

I did a little experimenting and if you have the Drop Tank Selector to ALL OFF and drop the tanks, the engine keeps running.

But, if you jettison them when the selector switch is in the any other position with the engine feeding off the drop tanks it will flame out.

If they are empty the engine will continue to run in a position other than ALL OFF.

Ed


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