Thank you for all of this info Steve, it will be a big help as I
reconstruct mine. My current plan is pretty much in line with what you
have done so far. At the end I should come out of this with a more
robust tank with a greater volume and a better CofG that I get now using
the Europa long rage axillary tank that sits in the baggage bay. Will
let you know how I get on.
Regards
Sue and Bill Sisley
On 14/11/2013 5:19 p.m., hagargs wrote:
>
> --
>
> Bill:
>
> I had been in the same tank situation as you. However the issue
> occurred at about 20 hours just as all the flight testing had been
> completed. The plane was down for maintenance and I drained the
> gas out of the tank as it was getting stale. Upon filling some
> time later gasoline started coming out of the plane almost as fast
> as it was being put in. Having the tank dry caused it to shrink
> back from its fuel expanded shape . The tank pulled away from one
> of the fiberglass mounts causing a good sized tear.
>
> I was pretty soured at the situation as the tank is really the
> first thing put into the cockpit . After doing some research I had
> found out there are kit car companies out there that offer
> rotationally molded polyethelyne tanks. The sell them with one
> caveat. They will absolutely not warrantee them if they are
> fiberglassed into the car as instructed to in the Europa. My
> soured disposition turned to one of disgust. That along with
> changed priorities and financial situation has led to the plane
> being grounded for I dont know how many years. The serial # is
> 143 so count from there. She gets pushed out in the driveway about
> every 10 weeks or so and the 914 is run for an hour cycling up and
> down at different RPM levels to prevent engine atrophy.
>
> However I did spend some time at getting a new tank designed for
> aluminum construction and have a few thoughts, suggestions and
> many photos to provide. I am a mechanical engineer in an
> industrial facility and am presented with the opportunity to
> perform many design and repair/rework efforts that are similar to
> this .
>
> The first issue is the fact that the tank does not come out whole
> if you want to leave the joggles that form your door window sills
> in place. I did not want to mess with these as they perform a
> major stiffening function in the fuselage top. The tank was cut up
> to get it out after taking the backrest top off. I do have a
> replacement polyethylene tank and attempted to place it in after
> making some spreader bars to perhaps push the fuselage out to
> allow the tank to drop back in. This was not successful as the it
> was putting too much stress on the structure for my liking. So it
> was on with designing an aluminum tank as was my original plan.
>
> Now if you have some time to spend and are willing to look at
> things in a different way I believe you can come up with something
> much better than the original design. I had seen the aluminum tank
> design and how it closely approximates the original. I was going
> to approach it the same way. I faced some trepidation seeing all
> the welding and pockets and curves in the front section of the
> tank to clear the aileron mechanism spar etc and still keep an
> acceptable volume in the tank.
>
> The original tank is 41 wide, the replacement unit would have to
> be about 2.5 narrower in order to make it an easy
> re-installation. This is conservative .When ever I design one
> thing to fit in another and one of the pieces is a big project as
> far as time an money goes I have never been sorry in 20 years by
> making it fit loose instead of tight. Its a lot easier to take up
> space than it is to make new space. However I would be losing
> volume . I thought the tank was too small to begin with. (I did
> have the extended range tank, that has a new home in Erich
> Trombleys bird). However with the top of the back rest off and
> looking at the stock tank , it became readily apparent that there
> was an opportunity to be had. The largest horizontal cross section
> of the tank is at the top. This will give the greatest incremental
> increase in fuel capacity for each incremental increase in height.
> Using a conservative measurement of 38 span wise and 11 wide you
> get about 1.75 gallons for each inch in height. There are also
> other opportunities to be had.
>
> Now with this thought in mind I saw that the complications with
> forming the aluminum and shaping the replacement like the original
> with tight clearances down low are slowly fading away. Design for
> excess clearance in order to make mounting and access for
> maintenance easier and make up the lost volume up high. The CG
> will also favor the front (the good direction). Without the
> complicated shapes the whole tank may be able to be made with 5 to
> 7 larger pieces with less welding required (see photos with
> patterns). My tank pattern has much more clearance around the spar
> and aileron bell cranks. The central tunnel is much larger. You
> can get your hands inside from the access panels. I had thought
> about having all the fuel fittings come out in the tunnel pointing
> in to the center instead of coming out the front of the tank to
> make re plumbing it easier.
>
> The tank comes up in height several inches, but also it is built
> up to form the mounting surface for the back rest pads as shown.
> The space between the 2 rests has been omitted and it is one
> continuous cross section from left to right. With this tank I
> would also get rid of the fuel filler cobra. Note the cap on the
> aluminum fuel cell in the photos. A cap like this would go on the
> right side of the right head rest area just inside the door. You
> open the door to refuel. This is what is done when the extended
> range tank is filled anyway. The large opening makes filling easy
> and does not present the venting issues with the cobra. My rough
> calculations give the tank about 3~4 gals greater fuel capacity
> than original.
>
> You will also be able to customize your reserve side to your
> liking as you will need to put a baffle in for stiffening. A
> suggestion would be to make the baffle all the way to the top and
> add perforations on the top side to dampen fuel sloshing from left
> to right when banking. When re-plumbing the line to the reserve
> side adding a T to it and going back to the primary side will
> allow you to use the fuel left in the main when you switched to
> the reserve. You will have to put a check valve in to keep from
> drawing on the reserve during normal operation.
>
> Of course you need to design in all the fittings. vents, return ,
> fuel gauge etc. Put in a ball valve for draining and an extra
> fitting for aux fuel hook up.
>
> Caveats:
>
> I have not built up the tank , but use these thoughts and photos
> as a guide of sorts to start the effort. This is how I would do
> it. Kim Prout inspected my original build and had no qualms with
> my workmanship and techniques. The plane flew hands off and was
> very stable. At this time there are no plans to ever fly it again.
> I may decide to part it out when I get tired of pushing it in and
> out of the garage.
>
> It looks like I can only attach 3 photos at a time so I will send
> additional reply submissions
>
> Steve Hagar
>
> A143
>
> Mesa, AZ
>
> ---Original Message-----
> From: bill
> Sent: Nov 11, 2013 3:43 PM
> To: europa-list@matronics.com
> Subject: Re: Europa-List: XS Fuel Tank
>
> Thank you Nigel,
>
> Having got the top off now I can see that the leak is at the shelf on
> the front of the tank where it sits on the mount. It appears that the
> fibreglass had bonded to the tank and with movement caused a fracture
> due to the stress. Having looked at the tank now which is very
> deformed
> and reducing capacity, I am sure a "metal" one will be much superior.
> Fortunately there are some very good craftsman around here so
> fabrication will not be a problem. Not sure we will get to the same
> volume as you have but will certainly look for more than I have now.
> Will send some pic,s when all done.
>
> Regards
>
> Sue and Bill Sisley
> On 12/11/2013 8:55 a.m., nigel_graham@m-tecque.co.uk wrote:
> > Hello Bill,
> >
> > I'm a bit late getting back on this one but as others have said, I
> > built a tank out of 5251 quarter-hard magnesium alloy.
> > It weighs 7850 grams and has a capacity of 110 litres.
> > I incorporated internal baffles, and breathers with proper AN
> fittings
> > to accommodate alloy pipework. It is also fitted with a full length
> > capacitive probe and four solid-state optical fuel level sensors.
> > http://www.europaowners.org/main.php?g2_itemId=28719
> >
> > The only advice I would offer is: allow yourself a long time to
> make and perfect your cardboard templates - the fuselage is partly
> conical in section so the development will be an interesting
> shape. Choose a welder based on his ability to weld alloy and
> don't fall into the trap I did of restricting yourself to a CAA
> approved welder whose self-belief exceeded his ability!
> >
> > Nigel
> >
> >
> > On 08/11/2013 21:37, bill wrote:
> >>
> >> After 1100hrs I have suffered a failed fuel tank on my XS Mono.
> Not
> >> sure exactly where the fault is other than it is high up on the
> tank.
> >> Will know more when I get it out.
> >>
> >> My question to the forum is, has anyone tried fabricating a metal
> >> (aluminium) tank rather than using the Polyethylene plastic one as
> >> supplied with the kit. If so, were you able to obtain the same
> volume
> >> and any other advice you may be able to offer.
> >>
> >> Many thanks
> >> XS Mono
> >> Kit 456
> >> 914 and Airmaster
> >> 1100hrs
> >>
> >>
> >> Sue and Bill Sisley
> >>
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