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ACRO E-mail Archive Thread: [Acro] Re: Extra aileron actuator arm attachment

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ACRO E-mail Archive Thread: [Acro] Re: Extra aileron actuator arm attachment


Thread: [Acro] Re: Extra aileron actuator arm attachment

Message: [Acro] Re: Extra aileron actuator arm attachment

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From: "Philipp Hilker" <philipp at>

Date: Fri, 29 Mar 2002 10:20:51 UTC


  Hi Ian,

sorry to offer you just a guess, but since you won't have a bolt locking eg.
safetywire on the outside, you will need a selflocking nut or drilled bold
with cotter pin and castle nut on the inside.

That's the engineering side. Walter won't have done it any other way.

But if you are a patient guy, you may use the following technique with
simple tools:

Locate the front edge of the spar

Take a large coin (at least 1 1/2 inch better 2) or jam glass cap and draw a
circle around the position of the nut.

Remove the paint within that circle. The paint will be aprox. 0.4 to 0.6
millimeter , so you may use a sharp blade like used my scaleplane builders .
Once you got a start, you will be able to remove the paint easily without
hurting the fabric. All this will you do to recover it later with a small
round patch of fabric.

Now you may already  apply new ceconite super seam fabric cement. This  you
do so early because after cutting the need hole into the fabric the edges
would bend more in- or outward.

Let is dry for half an hour and than cut your hole. It just needs to have
the size of  your wrench.

Take some adhesive tape and add it to the wrench. From the outside you might
have to reduce the outer diameter of the nut-wrench to fit it onto the
bolthead within the bracket.

From their on it's a ball game. Disassemble bolts and nuts. The large washer
on the inside will probably stay at the spare due to sticking to the paint
on the wood. Else you will have to catch it with a srewdriver and some
sticky tape before it false down and rolls away. If it happens use a
clothwrapped magnet to bring it to your hole.

Assemble every thing again, use a new selflocking nut and place a pinked
patch over your hole.

After that apply for a job as gynecologist and you might be able to pay for
your 230 AND  a twoholer.

Now I got to start my old jodel to Juist a small island in the northern sea.

Mit Hals- und Beinbruch

Philipp Hilker

Pitts S2a  D-EXPH
Jodel D117a D-EACI
Lo-100 D-7163

based in EDKD

----- Original Message -----
From: "Ian Scott" <ian.scott at>
To: <acro at>
Sent: Friday, March 29, 2002 9:08 AM
Subject: [Acro] Extra aileron actuator arm attachment

> Hello,
> Yet another question.
> Would anyone know how the aileron actuator arms are attached to the
> of Extras (Extra 230's in particular). From what I can see the bracket is
> attached with two bolts to the aileron spar. I'm wondering what these
> into. Are there blind nuts on the other side of the spar or are there
> ordinary locking nuts (which would mean the fabric on the aileron would
> to be opened up to remove the bolts).
> I spotted what appears to be a small crack running along the radius of one
> of the actuator arms yesterday. It may be a scratch where someone has
> scratched off the paint in order to allow an inspection of the bare metal
> however I can't remember seeing it before so we will do a dye penetrant
> check today.
> The aluminium variety of these actuator arms have a history of cracking
> as such, have an AD which requires regular inspections. Replacement with
> steel arms cancels the AD. I have the steel actuator arms.
> I'll let the group know what we find out.
> Best regards,
> Ian


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