How big of a deal is hail damage?

bflynn

bflynn

Final Approach
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Brian Flynn
Don’t like to see that much hail damage. Some on the ailerons is not unusual since the skin is really thin there on many aircraft, but the wing upper skin appears to have a lot of damage and pictures typically don’t look as bad as the real thing so it could be much worse.


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I imagine this being a composite wing complicates things.
 
Is the wing skin being smooth aesthetic or is there some aerodynamics involved? (rhetorical question)

As said earlier, the pictures don't tell the story. Need to see and touch that plane to determine the extent of what can only be called damage.
 
cowman said:
I imagine this being a composite wing complicates things.
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Bonded, not composite. They used Elmer’s glue or something and fergot to put in the rivets.

Anyway, the average airframe mechanic isn’t going to be able to fix this on a Friday afternoon.
 
Make an offer that you are comfortable with, see what happens.

They can kill ya but they can't et ya, that would be against the law.
 
It’s cosmetic and more than likely not a structural issue. Looks bad, doesn’t affect the flying qualities. Might be a good deal. If I bought it right, I would fly it as is and not worry about it.
 
Greg Bockelman said:
It’s cosmetic and more than likely not a structural issue. Looks bad, doesn’t affect the flying qualities. Might be a good deal. If I bought it right, I would fly it as is and not worry about it.
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Stressed skin is slightly weakened by the thinning associated with the deformation. As you say probably not a structural problem and it has probably flown many years with the dents.
 
The only way to repair hail damage is to replace the skin.
To do that on a Grumman is a huge PITA, the skins aren't just riveted on, they must be rolled to fit. then all must be cleaned up and glued in placed. I don't know if the proper glue is available any more.
 
Clark1961 said:
Bonded, not composite. They used Elmer’s glue or something and fergot to put in the rivets.

Anyway, the average airframe mechanic isn’t going to be able to fix this on a Friday afternoon.
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Composites are bonded.

Assuming it is bonded aluminum honeycomb composite, if it's disbonded or if the dents are beyond manufacturers limits, it is serious. If it is not, and it's just aesthetics, sanding, aerodynamic filler and a paint job should do.
 
Greg Bockelman said:
It’s cosmetic and more than likely not a structural issue.
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I'm not so sure about that, how durable is the glue holding the skins when the metal is bent where it is bonded?
 
GlennAB1 said:
Composites are bonded.

Assuming it is bonded aluminum honeycomb composite, if it's disbonded or if the dents are beyond manufacturers limits, it is serious. If it is not, and it's just aesthetics, sanding, aerodynamic filler and a paint job should do.
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It’s not honeycomb. It’s a simple aluminum skin. The Grumman design isn’t a composite by any stretch of the imagination.
 
GlennAB1 said:
Composites are bonded.

Assuming it is bonded aluminum honeycomb composite, if it's disbonded or if the dents are beyond manufacturers limits, it is serious. If it is not, and it's just aesthetics, sanding, aerodynamic filler and a paint job should do.
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On the Grumman the wing skins are not honey comb. they are simple single layer aluminum 2024-T3 over ribs.
 
Clark1961 said:
It’s not honeycomb. It’s a simple aluminum skin. The Grumman design isn’t a composite by any stretch of the imagination.
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The floor and belly plank that gives the aircraft its stiffness is honey comb. but being the bottom of the aircraft it would never get hit by hail.
 
GlennAB1 said:
If it is not, and it's just aesthetics, sanding, aerodynamic filler and a paint job should do.
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Here we go again, Glen wants to sand that aluminum skin.

Where will you get approval to do that repair?
Some Job card?
 
Tom-D said:
The floor and belly plank that gives the aircraft its stiffness is honey comb. but being the bottom of the aircraft it would never get hit by hail.
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So your post is pointless in this thread on hail now isn’t it.
 
Reading the ad, I see it is hangared,, too bad it wasn't once.
 
Clark1961 said:
So your post is pointless in this thread on hail now isn’t it.
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I don't understand your statement, I simply made the point the only honey comb was the belly plank, and it would be next to impossible to get hit with hail

So much worries about honey comb, well the honey comb is well protected.
 
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Tom-D said:
The only way to repair hail damage is to replace the skin.
To do that on a Grumman is a huge PITA, the skins aren't just riveted on, they must be rolled to fit. then all must be cleaned up and glued in placed. I don't know if the proper glue is available any more.
Click to expand...

There are a few people that can do the re-skin easily, glue isn't the a problem, ain't cheap though
 
1RTK1 said:
There are a few people that can do the re-skin easily, glue isn't the a problem, ain't cheap though
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You are right re-gluing isn't the problem, rolling the skins is, not many slip rollers big enough to do it.
I know there are facilities that can and will do the re-skining, but shop labor rates pretty much make doing it impractical.
and to add a thought, Grumman has a very good structural repair manual, that dictates how this will be done.
 
Tom-D said:
I don't understand your statement, I simply made the point the only honey comb was the belly plank, and it would be next to impossible to get hit with hail

So much worries about honey comb, well the honey comb is well protected.
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I understand that you can’t understand. It’s okay Tom, we all have our limitations.
 
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GlennAB1 said:
Well, structural adhesive bonding information is found in the composites area of structural repair manuals of every aircraft Ive worked on.
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Grumman Structural repair manual is on line.
show us the info.
 
Tom-D said:
Here we go again, Glen wants to sand that aluminum skin.

Where will you get approval to do that repair?
Some Job card?
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Who said sand the aluminum? The subject aircraft is painted and if aerodynamic filler is allowed you will probably be required to scuff the surface to provide better adhesion.

I mentioned the manufacturers manual, I like to use those unlike you.

Stick to your required checklist. That's your job card.
 
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Tom-D said:
Try me..
the one you need to view is here
http://www.grummanpilotsassociation.com/wp-content/uploads/2016/11/AA1-Series-Maintenance-Manual.pdf
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Make sure you read the first two paragraphs in that manuals structural section.

"This information should be used in conjunction with A.C. 43.13-1"

and

Field repairs... "normally covered with epoxy filler to maintain surface contour and smoothness"

They obviously have no problem with the use of aerodynamic filler.

Anything else you need me to find for you?
 
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We bought our Cherokee with some hail damage. Not nearly as bad as your pic, but it’s noticable. The plane flies just fine, and I didn’t consider it damaging to the value. I think with that amount of damage I’d have to offer a low price. Any airplane is a good deal if you get it at the right price and it’s what you want.
 
With that many dimples, it becomes a plus if you ever have to land on a golf course.
You can get more backspin and shorten the landing.

Seriously: I flew a friends Piper 180 for years.Then it got a lot of hail damage after being caught out on a ramp in Indiana.
After the damage the plane was a couple of knots slower on the high end, and a couple of knots faster on the bottom end.
We "re-calibrated" everything and put the new charts in the POH. He's still flying the plane.
He calls his plane "Maxfli".
 
A friend had hail damage on his Skylane. Insurance cut him a check for what they felt the damage did to the value of his aircraft. I think he eventually sold it for that much less. He said it didn't affect the aircraft's performance at all.

Sooner or later just about all aluminum aircraft will have hail dents. Pretty unavailable if they're flown.
 
GlennAB1 said:
Make sure you read the first two paragraphs in that manuals structural section.

"This information should be used in conjunction with A.C. 43.13-1"
Click to expand...

Yes, Grumman actually tells us to use the AC 43 for repairs.
 
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