Date
1 - 11 of 11
Wing Load Testing -- Wing damage
Mike Perry
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
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
Mike Perry
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:
toggle quoted message
Show quoted text
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
Kevin Boddicker
Mike,
Follow the repair plans in the plans manual. I think it states to
sand back each ply and expose at least one inch of each ply. So the
sanding needs to be a sort of scarf. Then
re-apply the glass cloth in it's original place per the lay-up
schedule. Then apply one bid over the whole repair. I think it is in
chapter three of the plans.
My opinion is that to test without the repairs would be a waste of
time. It would be interesting, but not much value to the question at
hand.
Kevin Boddicker
Tri Q 200 N7868B 115.3 hours
Luana, IA.
toggle quoted message
Show quoted text
Follow the repair plans in the plans manual. I think it states to
sand back each ply and expose at least one inch of each ply. So the
sanding needs to be a sort of scarf. Then
re-apply the glass cloth in it's original place per the lay-up
schedule. Then apply one bid over the whole repair. I think it is in
chapter three of the plans.
My opinion is that to test without the repairs would be a waste of
time. It would be interesting, but not much value to the question at
hand.
Kevin Boddicker
Tri Q 200 N7868B 115.3 hours
Luana, IA.
On Jan 20, 2009, at 3:53 PM, Mike Perry wrote:
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:home.
I picked up the wing this weekend from Sam Kittle and brought itThe wing was cut out of the fuselage with a sawzall and their isdamagein two areas. (The fuselage is going to be used in a motorglider.) Iam asking for opinions on repairs.but does
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 corenot enter the spar caps.wall and
The rear edge of the wing has 2 cuts parallel to the fuselageabout 1 inch in. The longest of these is about 3.5 inches in length.the
In all cases the damage appears to involve the 45 deg Uni but notspar 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
Sam Kittle
Mike,
I am sorry we didn't spend more time on this subject Saturday. I recommend
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 would
be best. However, I am not an engineer.
Sam
_____
From: Q-LIST@... [mailto:Q-LIST@...] On Behalf Of
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@...
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:
toggle quoted message
Show quoted text
I am sorry we didn't spend more time on this subject Saturday. I recommend
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 would
be best. However, I am not an engineer.
Sam
_____
From: Q-LIST@... [mailto:Q-LIST@...] On Behalf Of
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@...
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
quickheads2 <groups@...>
For your convenience, as Sam pointed out, the directions are here:
http://www.quickheads.com/Q2-Plans-Chapter-3-Page-3-19.html
Cheers,
Dan Yager
www.quickheads.com
--- In Q-LIST@..., "Sam Kittle" <skittle@...> wrote:
http://www.quickheads.com/Q2-Plans-Chapter-3-Page-3-19.html
Cheers,
Dan Yager
www.quickheads.com
--- In Q-LIST@..., "Sam Kittle" <skittle@...> wrote:
recommend
Mike,
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.lines would
For testing, I would think supporting the wing at the fuselage
be best. However, I am not an engineer.Behalf Of
Sam
_____
From: Q-LIST@... [mailto:Q-LIST@...] On
Mike Perrytesting,
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@...
Subject: Re: [Q-LIST] Wing Load Testing -- Wing damage
I am still looking for ideas on repair of the wing prior to
esp. the leading edge where it attached to the seatback bulkhead.to
I would also like to hear any ideas for how to jig the wing prior
testing since the wing is no longer attached to the fuselage.home.
Mike Perry
Mike Perry wrote:
I picked up the wing this weekend from Sam Kittle and brought it
damageThe wing was cut out of the fuselage with a sawzall and their is
glider.) Iin two areas. (The fuselage is going to be used in a motor
cutam 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
but doesabout 1 inch from the bulkhead. This cut exposes the foam core
wall andnot enter the spar caps.
The rear edge of the wing has 2 cuts parallel to the fuselage
length.about 1 inch in. The longest of these is about 3.5 inches in
not the
In all cases the damage appears to involve the 45 deg Uni but
Whatspar caps.
Two questions: Do we need to repair these areas before testing?
repair would you do on the leading edge?
Thanks for any help --
Mike Perry
[Non-text portions of this message have been removed]
Mike Perry
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:
toggle quoted message
Show quoted text
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:
Mike,
I am sorry we didn't spend more time on this subject Saturday. I recommend
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 would
be best. However, I am not an engineer.
Sam
_____
From: Q-LIST@... <mailto:Q-LIST%40yahoogroups.com> [mailto:Q-LIST@... <mailto:Q-LIST%40yahoogroups.com>] On Behalf Of
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@... <mailto:Q-LIST%40yahoogroups.com>
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
Mike Perry
I guess I should add, initially I was thinking the areas might not need to be repaired because they are inside the fuselage and not part of the spar-cap, but I now realize that's not the way to approach this problem.
Mike Perry
Mike Perry wrote:
toggle quoted message
Show quoted text
Mike Perry
Mike Perry 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:recommend
Mike,
I am sorry we didn't spend more time on this subject Saturday. Ifollowing the Q2 plans for the repair, page 3-19 para 4.2.would
For testing, I would think supporting the wing at the fuselage linesbe best. However, I am not an engineer.<mailto:Q-LIST%40yahoogroups.com>
Sam
_____
From: Q-LIST@... <mailto:Q-LIST%40yahoogroups.com>[mailto:Q-LIST@... <mailto:Q-LIST%40yahoogroups.com><mailto:Q-LIST%40yahoogroups.com>] OnBehalf Of<mailto:Q-LIST%40yahoogroups.com>
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@... <mailto:Q-LIST%40yahoogroups.com>Subject: Re: [Q-LIST] Wing Load Testing -- Wing damagedamage
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 isdoesin 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,___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
In Waddelow's test of the main wing and subsequent failure he felt that if the wing had been glassed in place to a fuselage just like in real life the results would have been different.
The compressive side of the wing (top) is held in place and the moment arm is moved out by being glassed to the fuselage sides.
You would actually get an extra external rib at the fuselage sides.
I believe the the main wing failed in the middle in Marc's test which probably wouldn't happen if glassed in place. I would probably happen out side the fuselage 1st.
If you compare apples (original wing) to oranges (Waddelow's) the Waddelow has extra step down shear web (bid) across the back plus tapered spar caps. There is also a BID layer across the top and bottom out to about BL 15. Plus BID 6" wide from front to back matching the fuselage sides Heavier but stronger.
Is the main wing a Waddelow? It would be nice to test both types for comparison. But then who has the time to build and do that.
Bruce Crain
N96BJ
____________________________________________________________
Click to find the latest solutions to enhance your small business.
http://thirdpartyoffers.juno.com/TGL2131/fc/PnY6rbut0fcMoUpj9t7gK8jhmltorabfqRerqsKv9F3vx26piMhte/
The compressive side of the wing (top) is held in place and the moment arm is moved out by being glassed to the fuselage sides.
You would actually get an extra external rib at the fuselage sides.
I believe the the main wing failed in the middle in Marc's test which probably wouldn't happen if glassed in place. I would probably happen out side the fuselage 1st.
If you compare apples (original wing) to oranges (Waddelow's) the Waddelow has extra step down shear web (bid) across the back plus tapered spar caps. There is also a BID layer across the top and bottom out to about BL 15. Plus BID 6" wide from front to back matching the fuselage sides Heavier but stronger.
Is the main wing a Waddelow? It would be nice to test both types for comparison. But then who has the time to build and do that.
Bruce Crain
N96BJ
____________________________________________________________
Click to find the latest solutions to enhance your small business.
http://thirdpartyoffers.juno.com/TGL2131/fc/PnY6rbut0fcMoUpj9t7gK8jhmltorabfqRerqsKv9F3vx26piMhte/
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
enough.
I'm sure that the bulkheads to contribute to the strength of the entire
assembly.
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
www.samhosoksins.blogspot.com
toggle quoted message
Show quoted text
really know is how a repaired wing holds up - not a new one. Maybe that's
enough.
I'm sure that the bulkheads to contribute to the strength of the entire
assembly.
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
www.samhosoksins.blogspot.com
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:recommend
Mike,
I am sorry we didn't spend more time on this subject Saturday. Ifollowing the Q2 plans for the repair, page 3-19 para 4.2.would
For testing, I would think supporting the wing at the fuselage linesbe best. However, I am not an engineer.Q-LIST%40yahoogroups.com <Q-LIST%2540yahoogroups.com>>
Sam
_____
From: Q-LIST@... <Q-LIST%40yahoogroups.com> <mailto:[mailto:Q-LIST@... <Q-LIST%40yahoogroups.com> <mailto:Q-LIST%40yahoogroups.com <Q-LIST%2540yahoogroups.com>>] OnBehalf OfQ-LIST%40yahoogroups.com <Q-LIST%2540yahoogroups.com>>
Mike Perry
Sent: Tuesday, January 20, 2009 1:53 PM
To: Q-LIST@... <Q-LIST%40yahoogroups.com> <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
Paul Buckley
How about those two cuts in the trailing edge?
If they are on the centre section inside the fuselage they will have severed the shearweb.
If outside then the 3.5" cut may have come close.
If the shearweb is intact I would first close out the exposed foam by tying the top and bottom skins together, probably with BID, and then glass both front and rear of the centre section to sturdy plywood to simulate the bulkheads,
The way I see it is that the 45 deg. UNI is there to prevent torsional twisting, although it does contribute a little to spanwise strength.
Regards
Paul B.
toggle quoted message
Show quoted text
If they are on the centre section inside the fuselage they will have severed the shearweb.
If outside then the 3.5" cut may have come close.
If the shearweb is intact I would first close out the exposed foam by tying the top and bottom skins together, probably with BID, and then glass both front and rear of the centre section to sturdy plywood to simulate the bulkheads,
The way I see it is that the 45 deg. UNI is there to prevent torsional twisting, although it does contribute a little to spanwise strength.
Regards
Paul B.
----- Original Message -----
From: Mike Perry
To: Q-LIST@...
Sent: Wednesday, January 21, 2009 4:17 AM
Subject: Re: [Q-LIST] Wing Load Testing -- Wing damage
> > > 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.
> > >
.
From: Mike Perry
To: Q-LIST@...
Sent: Wednesday, January 21, 2009 4:17 AM
Subject: Re: [Q-LIST] Wing Load Testing -- Wing damage
> > > 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.
> > >
.
Mike Perry
Thanks Paul:
The shearweb is involved with one of the cuts (the other goes barely into the top surface of the wing). I plan to repair the shearweb the same way I repair the rest of the glass.
I am thinking of glassing the wing to plywood as you describe -- but the Prof wants the students to solve these problems for themselves. (I keep asking questions here so I know what I'm talking about when I meet with the students. Unlikely I'll succeed, but I keep trying)
Mike Perry
"I may be older but I refuse to grow up."
Paul Buckley wrote:
toggle quoted message
Show quoted text
The shearweb is involved with one of the cuts (the other goes barely into the top surface of the wing). I plan to repair the shearweb the same way I repair the rest of the glass.
I am thinking of glassing the wing to plywood as you describe -- but the Prof wants the students to solve these problems for themselves. (I keep asking questions here so I know what I'm talking about when I meet with the students. Unlikely I'll succeed, but I keep trying)
Mike Perry
"I may be older but I refuse to grow up."
Paul Buckley wrote:
How about those two cuts in the trailing edge?
If they are on the centre section inside the fuselage they will have severed the shearweb.
If outside then the 3.5" cut may have come close.
If the shearweb is intact I would first close out the exposed foam by tying the top and bottom skins together, probably with BID, and then glass both front and rear of the centre section to sturdy plywood to simulate the bulkheads,
The way I see it is that the 45 deg. UNI is there to prevent torsional twisting, although it does contribute a little to spanwise strength.
Regards
Paul B.
----- Original Message -----
From: Mike Perry
To: Q-LIST@... <mailto:Q-LIST%40yahoogroups.com>
Sent: Wednesday, January 21, 2009 4:17 AM
Subject: Re: [Q-LIST] Wing Load Testing -- Wing damagewall andThe rear edge of the wing has 2 cuts parallel to the fuselage.about 1 inch in. The longest of these is about 3.5 inches in length.
___