Area Out / Capabilities
Area Out / Capabilities
(OP)
Hello,
I have an area out question.
On my (hypothetical) airplane control surface, some corrosion was discovered and trimmed out.
To determine the area loss/capability, is it the thickness of the material times the length (or width) of the trimmed surface?
So if the material was .063 inches thick, it would be Ftu(.063 x L), with Ftu used to determine a more conservative allowable.
Thank you in advance for answer my question.
I have an area out question.
On my (hypothetical) airplane control surface, some corrosion was discovered and trimmed out.
To determine the area loss/capability, is it the thickness of the material times the length (or width) of the trimmed surface?
So if the material was .063 inches thick, it would be Ftu(.063 x L), with Ftu used to determine a more conservative allowable.
Thank you in advance for answer my question.





RE: Area Out / Capabilities
Regards, Wil Taylor
Trust - But Verify!
We believe to be true what we prefer to be true.
For those who believe, no proof is required; for those who cannot believe, no proof is possible.
Unfortunately, in science what You 'believe' is irrelevant – "Orion"
RE: Area Out / Capabilities
Don A&P PE
RE: Area Out / Capabilities
"... surface, some corrosion was discovered and trimmed out.
To determine the area loss/capability, is it the thickness of the material times the length (or width) of the trimmed surface?
So if the material was .063 inches thick, it would be Ftu(.063 x L), with Ftu used to determine a more conservative allowable."
Also for a [simplified] longitidunal load example, Your equations should probably read Ftu x 0.063 x LT [sheet width] = load-max
Load-after localized corrosion blend-out ~ = Ftu x [(0.063 x LT sheet)-(blend-depth x LT width of blend)]
Note: this equation probably should have a Kt associated with it... to account for localized thinning at an arbitrary location across the psan of the skin.
Absolutely conservative would be to factor the blend depth across the sheet width.
CAUTION: cross-load cases would cause this problem to "blow-up".
I suspect You need to take a liaison engineering course, so You can see all the factors associated with damage analysis.
Regards, Wil Taylor
Trust - But Verify!
We believe to be true what we prefer to be true.
For those who believe, no proof is required; for those who cannot believe, no proof is possible.
Unfortunately, in science what You 'believe' is irrelevant – "Orion"
RE: Area Out / Capabilities
Quando Omni Flunkus Moritati
RE: Area Out / Capabilities
I am not the OP however it seemed like he was doing a repair of a light aircraft, and reading 43.13 may get him were he needs to go faster than trying to learn stress analysis. I can do the former but not the latter.
RE: Area Out / Capabilities
Take it from me... a 36-year practicing liaison/design structural/mechanicl enginurd... there is a LOT more about the direction of this question than meets the eye... and only formal liaison training could get him on a path where we can even begin to have a sensible discussion.
I am pretty close to red-flagging You and born2fly as non-engineers looking for engineering advice.
Regards, Wil Taylor
Trust - But Verify!
We believe to be true what we prefer to be true.
For those who believe, no proof is required; for those who cannot believe, no proof is possible.
Unfortunately, in science what You 'believe' is irrelevant – "Orion"