Fuel tank needed please.

[Neil Spooner]

If anyone has a spare fuel tank, either damaged/leaking or in good order they could spare I would like to develop a larger capacity aerobatic one.
Any thing gratefully received !
Neil

[Bumblebee Girl]

Hi Neil

When I had my fuel tank replaced about 18 months ago, I gave the old 30 litre one to John Brompton. G-XD. I can’t remember what he wanted it for and it may be that he still has it and it’s going spare. I’ll be seeing him this weekend so I’ll ask.

Kind regards

Kate

[Paul1954]

Hi Neil,

Can I ask, are trying to develop a larger main tank that will also be available for aerobatics?

[Neil Spooner]

Hi Paul,
The idea of the fuel tank mod' is to produce a fuel tank that has about another 10-15L capacity. It will have a lower chamber where this fuel is stored and is kept full whilst there is fuel above it, it will retain the same filler, but will only have one outlet which will be via a flop tube, so there will be no need to change fuel supply. All this is to add safety. However, the aerobatic advantage is lost if you are operating a Nipper without inverted fuel/oil.
Best wishes,
Neil

[Paul1954]

Hi Neil,

OK, I’m now clearer on what your trying to do. A few things to consider when designing.

- The diagonal fuselage cross-tubes will probably dictate two separate tanks joined by tube or pipe work; Access could be tricky and require the existing mod that allows access to the pedal area by the simple removal of the small exhaust fabric protector cover plate - you know the one I mean?
- Will the fuel pump be able to lift the fuel from the new chamber?

A simpler method would be to copy/make/install the already deigned fuel tank mods developed by Barry, - remove cork fuel gauge and seal tube, fit new vent tubes, fit plastic tube fuel gauging , fit floppy tube, fit new 3-position fuel selector. Install a separate ‘suitcase’ fuel tank that sits between pilot’s legs, add plumbing/pump to feed to main tank.

If you are not familiar with these mods, I have pictures. From memory the original ‘suitcase’ tank was about 10 L - but it was removable and proven.

[Neil Spooner]

Hi Paul,
The triangular tank is a single tank, I it's a guesstimate of the capacity. I think 10L is realistic.
The use of multiple fuel tanks in an a/c without a starter motor (as in mostly VW Nippers) I believe is an engine stoppage waiting to happen, and I believe an untenable modification. My previous Nipper had a separate fuel tank from which fuel was transferred to the main tank. No fuel tank selection required, just transfer the fuel when there is capacity in the main tank, and if you were premature with the transfer the fuel just recirculated until there was capacity and the transfer pump was switched off.
There would be no issues with the ability of the fuel pump to "lift" the fuel, as the head will only be a matter of inches.
I would be interested in any photos of Barrys' set-up, but only from historic interest. How on earth was the tank filled? The space between your legs in a Nipper is minimal, I believe my set-up to be superior, the tank capacity was 15L.

[Paul1954]

Neil, Barry was able to install the suitcase fuel tank without issue. All down to good and thoughtful design. The clean cowling design and attention to detail allowed Yearby - Shuttleworth to be done without need for an on-route tech stop.

There was no issue with engine stoppage on 'YB as the fuel was transferred to the main tank when there was space available in the main.

I am pleased to hear you are content with your design so no need to post images of another design. However, I don't see a sump (low point) to collect and remove water and contaminates from your aux tank.

[Neil Spooner]

Hi Paul,
What isn't evident from the pictures is that the aux tank is not flat bottomed, but is deeper at the front, the photo of the tank was before the plumbing was complete, but you can see two bosses at the front/bottom of the tank (the deeper part) where there was a drain for the aux' tank.
The cowlings I had were a modified version of Barry Smiths excellent cowlings....mine were slightly longer as I had the Force 1 hub on my engine which extends the crankshaft by about 1.5", and I didn't want a gap behind the prop' spinner and the front of the cowling.
Neil

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Aux tank.JPG (2.71 MiB) Viewed 9478 times

[Paul1954]

Neil, forgive me, but although you say that there is a slope from rear to front, aren’t the two take-off points at the same level?

[Paul1954]

No idea what’s happening here.

[Paul1954]

No idea what’s happen here.