Re: Wing Load Testing -- Wing damage

Sam Hoskins

Sadly, I think you muffed it. You could repair, per plans, but all you will
really know is how a repaired wing holds up - not a new one. Maybe that's

I'm sure that the bulkheads to contribute to the strength of the entire

You might want to take some photos and show them to the engineering
professor and see what he/she says about it all.

Sam Hoskins
Murphysboro, IL

On Tue, Jan 20, 2009 at 10:10 PM, Mike Perry <dmperry1012@...> wrote:

Obviously I wasn't clear. I understand the basic repair process.
However, I am dealing with two areas that attached to bulkheads. Do
those bulkheads contribute to strength? Do they prevent twisting in some
way that is important to the strength?

I am mainly interested in the possible weakness at BL 40 suggested by
Marc Waddelow. I think I can do simple repairs of the wing without the
bulkheads, support the center section (what is inside the fuselage) and
load the wing to failure. If the wing fails at or beyond the load of
4200 lbs then we can quit worrying about Marc's analysis.

Other opinions?

(The engineering students will be doing their own analysis of this
problem. They and their professor are far better qualified than I to
decide what is an adequate repair and how to support the wing. I wish
we could have tested the wing still mounted in the fuselage, but life
got in the way last fall and now the wing is cut out of the fuselage.)

Mike Perry

Sam Kittle wrote:


I am sorry we didn't spend more time on this subject Saturday. I
following the Q2 plans for the repair, page 3-19 para 4.2.

For testing, I would think supporting the wing at the fuselage lines
be best. However, I am not an engineer.



From: Q-LIST@... <> <mailto: <>>
[mailto:Q-LIST@... <> <mailto: <>>] On
Behalf Of
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@... <> <mailto: <>>
Subject: Re: [Q-LIST] Wing Load Testing -- Wing damage

I am still looking for ideas on repair of the wing prior to testing,
esp. the leading edge where it attached to the seatback bulkhead.

I would also like to hear any ideas for how to jig the wing prior to
testing since the wing is no longer attached to the fuselage.

Mike Perry

Mike Perry wrote:

I picked up the wing this weekend from Sam Kittle and brought it home.
The wing was cut out of the fuselage with a sawzall and their is damage
in two areas. (The fuselage is going to be used in a motor glider.) I
am asking for opinions on repairs.

The front edge of the wing attaches to the rear of the seatback
bulkhead. In this area the wing was separated with a rather wavy cut
about 1 inch from the bulkhead. This cut exposes the foam core but does
not enter the spar caps.

The rear edge of the wing has 2 cuts parallel to the fuselage wall and
about 1 inch in. The longest of these is about 3.5 inches in length.

In all cases the damage appears to involve the 45 deg Uni but not the
spar caps.

Two questions: Do we need to repair these areas before testing? What
repair would you do on the leading edge?

Thanks for any help --

Mike Perry


Join to automatically receive all group messages.