Willie,
I can think of no reason why not.
The only point you need to check is the bolt head to rear bulkhead
clearance. The circumference of the TP9 and TP12 is only about 16mm away
---From this bulkhead - so the total assembly thickness is a limiting factor
and I'm not sure how deep a 3/8" bolt head is.
If this did prove to be a problem, small 1/4" to 3/8" step-down spigots
would solve the problem and allow you to use 1/4" bolts.
Nigel (The other one)
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com]On Behalf Of William
Harrison
Sent: 25 June 2007 12:09
Subject: Re: Europa-List: Tailplane flutter
<willie.harrison@tinyonline.co.uk>
Nigel,
Would there be any problem with doing this with 3/8 bolts on an
aircraft which had Mod 62 already done to it?
This is such an appealing idea I think.
Willie
On 25 Jun 2007, at 11:29, Nigel Graham wrote:
> <nigel_graham@btconnect.com>
>
> Hi Graham,
>
> FYI - I am working with Ian Rickard at the moment to document
> exactly what I
> did and present this to the PFA.
>
> To enlighten those of you not familiar with this mod:
> A long time ago I identified the inherent shortfall with the TP14
> method of
> securing the drive arms to the torque tube. Merely replacing these
> pins with
> oversized pins would not in my opinion, cure the problem - only
> delay the
> next re-occurrence once play developed.
>
> I developed a simple arrangement (KISS technology) that positively
> clamps
> the drive arms (TP9 and TP12) onto the torque tube by replacing all
> four
> TP14 pins with 1/4" x 2.125" AN bolts.
> To support the torque tube and prevent it distorting, 15mm wide
> cross-drilled discs are inserted into TP4 at each of the four
> stations.
> To spread the clamping load over a larger surface, "saddle
> blocks" (profiled
> to mate with the OD of TP9 and TP12) are fitted under the bolt head
> and
> castellated nut.
>
> The beauty of clamping is that it introduces a torque damper into
> the drive
> system - eliminating the shock "chattering" that wears the standard
> TP14
> pins and elongates the holes - and it can be retrofitted to tubes
> with worn
> holes.
>
> Nigel (The other one) Graham
>
|