Mike
No intention of ruining it for anyone but just need to know to live. The
thread wasn't started by me anyway see below.
If the information is there then let's have some acknowledgement that
the items have been properly normalised the PFA is a branch of the CAA
anyway. As I said I know my nose leg was normalised, but can't see why
it touches any raw nerve to ask about the rest, they may well be, but
let someone confirm it? I found a flaw in the material of my Jabiru
engine mount and the pro. who fabricated it couldn't believe he missed
it. So why shouldn't it be asked if this work has been done and more to
the point lets hear of the check of the status of those that cracked.
There's no such cracks on mine with a heavy engine and an exceptionally
heavy prop(but very correctly balanced) but then I did have the
foresight to redux some close fitting thick walled tube in place 7 years
ago, before any load cycles were applied. It is also conceivable that
the "gods in the PFA" won't accept my application for exemption.
After all some people just may prefer (having floated their engine
forward) to replace the whole landing frame having had some reassurances
that the new issue ones have been up rated and normalised instead of
doing mod 72.
If there is a shortfall of strength in existing frames so needing mod 72
then IMHO it is just conceivable that cyclic fatigue is already present
unless the frame was supported from scratch and prior to application of
any load whatever.
As you see I have not posted this rant on the full forum.
Regards
Bob H
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Mike Parkin
Sent: 20 January 2007 21:41
Subject: Re: Europa-List: Mod 72 question
Bob,
This is why we are able to operate our aircraft so cheaply. If you want
certificates and batch numbers, buy a certified aircraft and pay for
your annual and C of A. Also you would not be allowed to perform your
own maintenance. If you are not happy with the certified/experimental
world, then do not ruin it for those of us that are.
regards,
Mike
----- Original Message -----
From: R.C.Harrison <mailto:ptag.dev@tiscali.co.uk>
Sent: Saturday, January 20, 2007 9:34 AM
Subject: RE: Europa-List: Mod 72 question
Hi! Tom
This is now two photo's of failed items I've seen which, IMHO I have to
agree 100% with you every indication of fatigue is there. My training is
likely "old Hat" particularly considering modern alloy extruded tube but
I wonder what traceability exists of annealing/stress relieving :-
a) done to these and all frames ? (do certificates exist and where?)
b) what such heat treatment is actually called up on the metals and
complex joints in question?
c) what investigation has been undertaken with Rockwell Hardness tests
over the whole of the failed frames and in particular close to the
failure?
This is all shutting the gate after the horse has bolted but in the
total shape of things we need to know along with the question will new
ones be produced with up rated tubes and will they have an appropriately
designed heat treatment with a certificate?
NB I do have evidence that my nose leg has been "normalised".
Regards
Bob Harrison. G-PTAG
Robt.C.Harrison
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Tom
Friedland
Sent: 20 January 2007 04:52
Subject: Re: Europa-List: Mod 72 question
Hi Graham
I doubt that you will get an answer what caused the break. It looks to
be that it was most likely a tension break with perhaps some fatigue
factor. The upper tubes will have tension in the upper parts and that
will be increased by the thrust. There also could be some problem with
non annealed brittleness from the closeness of the weld.
The lower tubes should be ok as they have tension stress from weight
bearing but that is cancelled by compression.
But then what do I know. My engineering studies were 50 years ago! Now
I am just a dumb doc.
Tom
On 1/19/07, Graham Singleton <grahamsingleton@btinternet.com> wrote:
grahamsingleton@btinternet.com <mailto:grahamsingleton@btinternet.com> >
Roger
what type of failure was it, bending, shear or fatigue?
Graham
Roger Bull wrote:
>O.K. Bob, you woke me up!
>
>
>Rob Housman's answer is on the ball. Using Redux would necessitate
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Date: 20/01/2007 10:24
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