only)
Hi! Frans/Peter/all.
I would draw your attention to a simple fact that when the flaps are
extended at 82 knots a large proportion of the aircraft weight is
carried on the flap hinges. The hinges at the outboard end of the
flaps are integral with and cured in place as part of two ribs which
extend over the full width of the wing which in turn also is cured and
envelopes the wing spar thus spreading any loading over a massive part
of the wing structure.
These structural factors are I would venture to suggest likely
stronger than any integral tie down that could be separately
constructed into the wing anywhere else without such considerable
weight increase when an existing potential facility is already
available.
With regards to receiving snatch blows through the aircraft "bucking
about" this is entirely without foundation since on tying down through
these points it is possible to load up and deflect the main gear legs
to ensure the system is constantly in tension.
In conclusion I can advise that G-PTAG has always been tied down in
this manner and has withstood some severe gusting wind conditions
without any damage ensuing what or where ever over it's 900 hours life
time. However all this advice is provided without liability as to the
engineering capability suggested. In other words why don't you all do
as you prefer but with the benefit of Neville Eyre's information I
suggest you establish your own aircraft's integrity with regards to the
type of block in use.
May I thank Neville Eyre for his kind intervention on this matter and I
can confirm that the blocks on G-PTAG are aluminium alloy and were part
of it's original Mono Wheel Kit since the aircraft was originally built
as a convertible so embodying all things Trike and Mono together.
Best regards
Bob Harrison G-PTAG
-----Original Message-----
From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-
server@matronics.com] On Behalf Of Frans Veldman
Sent: 21 November 2011 16:11
Subject: Re: Europa-List: Eye bolt tie down through wing/flap hinge
block (trike only)
nl>
On 11/18/2011 08:04 PM, Bob Harrison wrote:
> Hi! Herewith a photo of the tie down location on the wing/flap hinge
block
> on G-PTAG .
Ehm, the flap hinge is designed for holding the flap in position.
Tying
down the aircraft with it imposes the hinge to possible jerking
loads,
in a different angle than the hinge is supposed to receive during its
intended use. I remember some notes about not using pencil marks on
this
apparently sensitive and critical part. Can anyone make an educated
guess whether using this part as tie down point would not compromise
the
attachment or strength of the hinge?
Frans
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