Hole in Cowling

NealRomeoGolf

NealRomeoGolf

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Is there a rule of thumb for what would deem the breach of a cowling (i.e. a hole) unairworthy? Hole size? Hole placement? Any hole at all?
 
NealRomeoGolf said:
Is there a rule of thumb for what would deem the breach of a cowling (i.e. a hole) unairworthy? Hole size? Hole placement? Any hole at all?
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Hole in cowling is kind of ambiguous. Could range from a stop drilled crack (ok) to a gaping hole after cylinder head fails (decidedly NOT ok)…..
 
NealRomeoGolf said:
Is there a rule of thumb for what would deem the breach of a cowling (i.e. a hole) unairworthy? Hole size? Hole placement? Any hole at all?
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Depends. If you are adding a hole to the cowling some fall under a major alteration per 43 Appx A. If you are repairing a hole in the cowling it follows other requirements.
 
Bell206 said:
Depends. If you are adding a hole to the cowling some fall under a major alteration per 43 Appx A. If you are repairing a hole in the cowling it follows other requirements.
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This would be a hole found on preflight that shouldn't be there. About half a cm square, maybe smaller.
 
NealRomeoGolf said:
This would be a hole found on preflight that shouldn't be there. About half a cm square, maybe smaller.
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So, something is rubbing against the cowling that shouldn't oughta be rubbing?
I would be less concerned about the cowl and more concerned about what is rattling around loose under the cowl.

But, I ain't no A&P.
 
NealRomeoGolf said:
This would be a hole found on preflight that shouldn't be there. About half a cm square, maybe smaller.
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How the hole got there would determine my level of concern about the hole itself. It would also be the deciding factor on if I flew the aircraft again before working on it to correct the problems found.
 
NealRomeoGolf said:
This would be a hole found on preflight that shouldn't be there. About half a cm square, maybe smaller.
Click to expand...
Technically, its a discrepancy and should be addressed. But as noted above, what caused the hole should be determined to ensure there are no other issues or any hidden damage.
 
I love you guys.

Remeasured it at .25mm so it's pretty small. A&P says I'm fine and he will patch it.
 
.25 cm is roughly 3/32 for those from 'Murica...or slightly larger than a c-hair for those that can't read a real tape measure
 
I'm not positive, but I think it's OK to use mm in Texas to describe artillery.

If it's 88mm, it could be German. I think 37mm could either be Russian or US. 20mm or 40mm could be just about anybody.
 
A hole that is 0.5 CM converts to 0.19 inches, or about 3/16 inch. I'm betting that somebody ran some equipment into it. On top, on the side, the front? Metal or FG? Engine OK? 0.177 is an air rifle caliber.
As 206 said, FAR 43 Appendix A, Para (C) preventive maintenance is authorized if you are the owner, pilot or operator. There is a list of the do-able things that you can do. #12 is: "Small simple repairs to fairings, cover plates, cowlings,....etc". I would go to a boater's supply store and pick up a fiber glass repair kit and don't look back.
 
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WDD said:
There are two types on countries. Those that use the metric system, and those that put a man on the moon.
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When America put men on the moon, Canada was still imperial. Inches and feet. The metric system wasn't mandated until about 1976 or '77, and even after 45 years we still buy lumber and plywood in inches and feet. And build houses that way. The supermarket has prices for metric weight and often in pounds and ounces as well. Us old guys still think in terms of miles and acres and stuff like that, and some of use are good at converting on the fly. When talking to young people we have to remember to give specs in metric. I can't tell a kid that my favorite lake is 1100 feet deep; got to tell him it's 330 metres deep. On POA I have to talk in 'Murican measurements. And spell words in 'Murican.

Primacy. Whatever is first learned is really hard to break. Not until everybody born before 1977 is dead will it go away here, and even then, if the US remains a world power, we'll still have to deal with the old systems.
 
One of the surprising things I learned during my recent trips to the UK is that the English still use feet, inches, miles per hour, etc. I'd have thought they'd gone metric by now, since their currency did back in 1971.

The other big surprise is that those people drink coffee ALL the time... don't know that I ever saw anyone drinking tea.
 
To be serious for a second - yeah, the metric system is much better. Knots, nautical miles, statute miles, inches of mercury, ……. It’s odd


Hey - we lead the work with soda in 2 liter bottles !
 
WDD said:
To be serious for a second - yeah, the metric system is much better. Knots, nautical miles, statute miles, inches of mercury, ……. It’s odd


Hey - we lead the work with soda in 2 liter bottles !
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And every auto engine is in liters.
 
Nautical miles and knots at least have a basis in physical geography.
 
Yup....he needs to keep looking for the oil leak. Hasta be with that round fired into it. o_O
Maxnr said:
A hole that is 0.5 CM converts to 0.19 inches, or about 3/16 inch. I'm betting that somebody ran some equipment into it. On top, on the side, the front? Metal or FG? Engine OK? 0.177 is an air rifle caliber.
As 206 said, FAR 43 Appendix A, Para (C) preventive maintenance is authorized if you are the owner, pilot or operator. There is a list of the do-able things that you can do. #12 is: "Small simple repairs to fairings, cover plates, cowlings,....etc". I would go to a boater's supply store and pick up a fiber glass repair kit and don't look back.
Click to expand...
 
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