Thank you John. Hadn't thought of that. Wonder if a check valve could be
used? Andair quotes < 0.7 PSI (< 0.05 bar), Rotax requires < 0.25 bar
for whole return line. Bad idea? Clogging would give carburettor
overflow. Two in parallel?
Jan de Jong
>
>> Hi all,
>>
>> I have a question if I may.
>> Mod 33 shows the starboard drain tank outlet used also as the return
>> line tank inlet.
>> The pictures I see with Graham Singleton's adapters for threaded
>> connections all show the return line going to the vent outlet if I'm
>> not mistaken.
>> Is this recommended, if so why?
>
> Several years ago I submitted a Modification request to PFA
> Engineering to cover a revised fuel system with aluminium pipes and
> home-brewed tank fittings, much like Graham's. The return feed went
> back via a drain outlet.
>
> Francis made several comments. One of them was that this return route
> was not the best as in the event of a serious engine bay fire in which
> the flexible hoses were destroyed it would be possible for fuel to be
> fed from the tank along this return line which could not be turned
> off. In theory most of the tank contents could feed the fire.
> Raising the return point to the vent inlet removed this possibility
> (unless you came to rest on the ground inverted, tail high).
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