Thank you Bud, Duncan and others for your input.
David Stanbridge reached out to me in response to my post here and I've
E-mailed them the pictures as well. Their recommendation was to remove
the rust and oil it to prevent further corrosion.
Now, my local mechanic and I decided to have me paint the W26A using
"hammer paint" after sanding. Here's to hoping that the parts will still
fit. It shouldn't rust anymore anyway...
The way I recall it, the W26B was correctly oriented when we found the
totally broken one. However, it had almost fallen off so I can't be
sure. The port side one however, which I later discovered to be cracked
as well, was correctly oriented. That is if I remember correctly. I
might again here just be assuming it was installed correctly due to
having read the builder's manual afterwards.
And yes, I am a member of the Europa Club and will sure check out the
914-tips, thank you all.
/ Erik
On 2020-09-07 17:10, D McFadyean wrote:
>
> The (substantial) wear marks on W26A show that is was installed the
> correct way around.
>
> The wear mark on the inside vertical surface of W26 just above the
> central bolt indicate that at some point W26A was leaning heavily on
> W26 in a 'negative g' direction of loading, which may explain how it
> then broke i.e. the weight of the wing transmitted in bending through
> the lift pin caused W26A to lever against W26.
>
> That wouldn't occur during a normal flight maneuver and when properly
> rigged. Perhaps the downward leverage occurred during derigging after
> removing the spar pins, and assuming the spar cups were misplaced.
>
> I'd check the lift pins for bending too and that these are not angled
> (or bent) above the centreline of the inboard spar projections (and/or
> that W26 has been set vertically).
>
>
> Duncan Mcf.
>
>> On 07 September 2020 at 14:31 Bud Yerly <budyerly@msn.com> wrote:
>>
>> Sorry to hear of your issues.
>>
>> The failure of the socket indicates the crash may have been more
>> severe than anticipated.
>>
>> In all my years, Ive seen corrosion on older socket parts that were
>> not as well protected as the new bits are. I have never seen a
>> failure in the 26A as this was a well engineered and tested part by
>> Europa. If installed backwards, this can happen.
>>
>> Please contact Europa Aircraft because the W26 part assembly has not
>> been an issue and replacement of the corroded items may be smart.
>> This area is a critical flight component and the annual inspection
>> and repair may have missed this part may have been damaged or
>> assembled incorrectly. If the socket inner W26B failed, was the
>> interior tube and attachments properly installed, checked and
>> inspected is the question.
>>
>> Loctite is between the barrel and that thin rectangular piece you
>> call it so they operate as a unit. The wing pin goes into the fully
>> assembled socket and allows it to move up and down just a bit. If
>> not Loctited the barrel can rotate and make pin insertion more
>> difficult. (Frankly, during wing install, simply note the
>> orientation of the barrel is all that is needed.) Note that the
>> assembly thin side goes on the fuselage side. Dont get that
>> backwards as it builds up stress and may be a part of the failure you
>> see.
>>
>> As far as the structural strength, the yoke piece 26A and the barrel
>> 26C carry the load of the wing pulling forward under max G load.
>> This barrel is designed to move up and down.
>>
>> As for the Rotax 914:
>>
>> There is a long and boring troubleshooting guide on my website on
>> keeping the 914 running true. The carbs are easily rebuilt with
>> proper attention to detail. I find the Rotax engine forum
>> informational, but doesnt cover in enough detail. I do find the
>> videos provided by Rotax to be quite complete. The paper I did
>> covers various phases and expands troubleshooting. See the
>> techniques section for an updated version since published in the
>> Europa Club magazine.
>>
>> Bud Yerly
>>
>> www.customflightcreations.com
>>
>> Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for
>> Windows 10
>>
>> *From: *Erik Dahlbck <mailto:erik@erikdahlbeck.com>
>> *Sent: *Sunday, September 6, 2020 5:18 PM
>> *To: *europa-list@matronics.com <mailto:europa-list@matronics.com>
>> *Subject: *Europa-List: Rear wing root socket problems
>>
>> Hello,
>>
>> First time posting here, hoping my attached photos are small enough,
>> etc...
>>
>> I'm trying to get Europa SE-XRX airworthy again after being grounded for
>> two years. At first due to some hard-to-diagnose carburettor problems.
>> 914 float bowls, enough said... If interested, I have a post about it
>> over at Rotax-Owners:
>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.rotax-owner.com%2Fen%2F912-914-technical-questions%2F6881-914ul-carburettor-gremlins%3Fstart%3D15&data=02%7C01%7C%7C8482b0ef213641821e7208d852aa5b72%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637350238926500351&sdata=pMvGV5%2BI41Zjnn3nQnSV8Wo37dGxDwnn9%2Ff%2Bu5P7T%2F0%3D&reserved=0
>>
>>
>> PROBLEM NO 1
>>
>> Anyway, after fixing the engine and while doing the annual together with
>> the previous owner/builder, it was discovered that the rear wing socket
>> housing, part W26B, starboard side, was cracked in two parts. Further
>> inspection showed that also the port side was cracked, albeit not having
>> split in two just yet. Please see attached photos.
>>
>> I've got the spares from the manufacturer however, I'm curious if this
>> is a known problem? Any thoughts on what could be the cause? Anything
>> further to look out for?
>>
>> My local mechanic seemed just as puzzled as I was when looking at how
>> thin this part is. I mean what is it, 2 mm?
>>
>> One thing to consider: The aircraft was built as a monowheel but crashed
>> on takeoff during flight testing, making a hard landing and a ground
>> loop. The incident was traced to a construction error in the control
>> line attachment to the rudder, causing alterations in the design (some
>> of might be familiar with this). The aircraft was then repaired (by some
>> sailplane workshop that seemed to know what they were doing, I've seen
>> the photos at least). Among other things it got a new tail, a CS prop
>> and was rebuilt as a trigear. Might this new discovery simply be residue
>> of that old incident?
>>
>> Also, the builder's manual states that the W26B and C parts should be
>> loctited together. However, there was no trace of this. I'm not sure if
>> that instruction has been there since the beginning or if it could be a
>> later revision? However, I sort of have my doubts as to some loctite
>> being able to strenghten this construction enough to not break from
>> whatever broke this...?
>>
>> Finally, any thoughts on how to reassemble these parts? Where does the
>> Loctite go? Just on the barrel and make sure the holes align before i
>> dries? How to you avoid getting loctite on the surfaces between the
>> barrel and the socket body (W26A)?
>>
>>
>> PROBLEM NO 2
>>
>> Due to various reasons, I only got around to cleaning the grease off the
>> rear socket assemblies, in preparation for reassembly, but doing the
>> loctite-work in a cold hangar, etc, and also enlisting the help of the
>> very busy local mechanic, was more than I could get done before last
>> winter.
>>
>> Now, on inspection, the W26A socket bodies show signs of corrosion.
>> Please see the other attached photos. Anyone have an opinion on just how
>> bad this is? Do they also need changing? And does that require
>> composite-work? I've been looking through the builder's manual but I'm
>> afraid I'm not quite up to understanding all of it.
>>
>>
>> Any thoughts on both of the above issues would be greatly appreciated!
>>
>>
>> Sincerely,
>>
>> Erik Gunneland Dahlbck
>> Linkping, Sweden
>> Europa SE-XRX
>>
>
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