"Soft spot" on the side of the fuselage

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salim
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"Soft spot" on the side of the fuselage

Post by salim »

Hello,

During one of my recent pre flight visits, I noticed this soft spot on the side of the plane.

Any idea of the cause, how serious it is, and how it can be fixed ?

Thanks a lot !

Salim
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pietromarx
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Re: "Soft spot" on the side of the fuselage

Post by pietromarx »

When you say soft ... what do you mean? Like you can push in with your hand? Or textured to the touch?

I am sure it can be fixed, but it may be a bit of an ordeal given where it is.
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salim
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Re: "Soft spot" on the side of the fuselage

Post by salim »

Thank you for your answer. Yes you can slightly push in with your hand.
No clue how something like that can happen
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pietromarx
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Re: "Soft spot" on the side of the fuselage

Post by pietromarx »

That's a classic sign of composite damage. (Usually one can tap along with a coin edge to see if there are acoustic changes between bonded and unbonded areas of the composite.) I would absolutely get that addressed with a shop who can make composite repairs. With luck it won't be too big a deal.
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Re: "Soft spot" on the side of the fuselage

Post by Lance Murray »

Take a quarter and do a tap test. See if you hear a difference in the dent area.
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salim
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Re: "Soft spot" on the side of the fuselage

Post by salim »

thank you for your answers ! any idea of the cause ?
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Re: "Soft spot" on the side of the fuselage

Post by ememic99 »

The place is very strange. If it was more forward, I'd say it could be the ice detached from prop. If it was somewhere more frontally, I'd say bird hit. if it was somewhere rear side of fuselage it could be hit in hangar during manoeuvring.
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Davestation
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Re: "Soft spot" on the side of the fuselage

Post by Davestation »

ememic99 wrote: Tue Mar 31, 2020 8:30 pm The place is very strange. If it was more forward, I'd say it could be the ice detached from prop. If it was somewhere more frontally, I'd say bird hit. if it was somewhere rear side of fuselage it could be hit in hangar during manoeuvring.
Agreed, that does not seem like the place to take damage. Could it just be a thinner section of the structure?
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Re: "Soft spot" on the side of the fuselage

Post by Antoine »

Davestation wrote: Thu Apr 16, 2020 2:24 am
Could it just be a thinner section of the structure?
The fuselage is normally rock solid at this location.
i guess the only reasonable explanation would be delamination due to poor resin diffusion during manufacturing...
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salim
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Re: "Soft spot" on the side of the fuselage

Post by salim »

So I got an answer both from Diamond and a service center.
It is a fairly common issue related with the fact the skin is thin at this location.
There is a void between the skin and the main structure, and in some conditions the aerodynamic pressure creates this defect.
It can be corrected fairly easily (1h) by injecting a filler from the inside.
But in any case they both say it is not essential and i can wait before doing it.
Best
Salim
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