Fuel tank orientation

[Walts]

Hi all, Just a quick question. Is there any reason why a fuel tank can not be installed vertically as opposed to laying down? I have serious space issues in the nose of the model. The picture shows both the tank and engine in question, in roughly the position they will be situated in the model in relation to each other.

Many thanks.

[Stuart Z]

I think the reason for a horizontal tank is the fuel height will only vary by a smaller amount compared to a vertical tank.  In your illustration you can see the fuel height will vary much more than the other way round.

S

[Don Fry]

It’s not an exact science. I used to own a Junior 60, and I used the tank as you proposed for many hundreds of flights without ever having an issue. But when I set the engine up, it was done with say half a tank of fuel in it to minimize the differences. That said, I flew a J60, trundling about. 
Inverted flight is out, clunk  not in the fuel, and acrobatics won’t end well as the G forces effect fuel flow. 
If you need a proper (normal) fuel flow, and you have room elsewhere for a second tank, a chicken hopper system is worth considering. But that needs careful planning, and the greater number of fuel pipes needs a bit more care to install and maintenance is more critical.

Edited August 22, 2021 by Don Fry
Spellchecker blues

[Walts]

OK. Thanks for the replies guys ?