Enough left to make restoration worthwhile?

[Saville]

Looking at the photos of the Honduran P-63, in another thread, I wonder:

How much airplane has to be left to make a restoration to airworthy status a reasonable thing? "Reasonable" depends upon how much money you have, I imagine. But I'd think there would be a point where it would be easier to build one from scratch rather than try to refurb one that had been on a stick for a while. I just wonder where that point is.

Are the spars and basic structure of a 60 year old plane usually in good enough shape to keep?

Is it the case that some refurbs are really built-from scratches with just a few parts of the original to maintain the tail number?

thanks

[bdk]

Are the spars and basic structure of a 60 year old plane usually in good enough shape to keep?

Is it the case that some refurbs are really built-from scratch with just a few parts of the original to maintain the tail number?

Everything is based upon condition. Either corrosion or induced damage (crash, mishandling, etc.) can condemn any part. Some parts can be spliced or straightened, others cannot. Some parts are cheaper to replace than to fix.

There are a surprising amount of usable parts even on the most corroded hulk or the proverbial smoking hole sometimes.

Building from a pattern is often far easier than building from a paper blueprint also.

[Randy Haskin]

I understand that often times it's the little parts...brackets, fittings, etc,...which can be obtained from a hulk which make a rebuild so nuch easier than with a ground-up construction just from scratch.

[Broken-Wrench]

Are the spars and basic structure of a 60 year old plane usually in good enough shape to keep?

Is it the case that some refurbs are really built-from scratch with just a few parts of the original to maintain the tail number?

Everything is based upon condition. Either corrosion or induced damage (crash, mishandling, etc.) can condemn any part. Some parts can be spliced or straightened, others cannot. Some parts are cheaper to replace than to fix.

There are a surprising amount of usable parts even on the most corroded hulk or the proverbial smoking hole sometimes.

Building from a pattern is often far easier than building from a paper blueprint also.

Amen

[Rob Mears]

Building from a pattern is often far easier than building from a paper blueprint also.

IMO, beginning a restoration / reproduction with what is effectively a complete airframe mounted in a jig makes things WAAAY more reasonable than beginning with a empty shop and a set of prints. The two circumstances aren't even comparable. Even the "new production" Me-262's, Zero's, and Ki-43's required the presence of a pattern airframe in order to be successful. The fact that Flug Werk successfully recreated their Fw-190's using only prints as the basis of their efforts is beyond astounding to me.

There are often discrepancies between the factory blueprints and the actual aircraft as well, not to mention the many thousands of small changes incorporated on the assembly line during the original production years. Even if every ounce of sheet metal on the FAH P-63 was replaced before all was said and done, it's value as a pattern plane would be most substantial to anyone wanting an airworthy P-63 for themselves.

[bdk]

Another thing most people don't realize is that airplanes are made off of master tools. Engineers define the shapes, but then tooling technicians have to turn two dimensional drawings (or now electronic 3D models) into actual master tool shapes to make drop hammer dies, stretch forming tools, etc. In the old days the drawings were all done by hand and the 3D representation made by the tooling department to create the master models had a great deal of "artisanship" involved. Two different artisans would invariably end up with slightly different shapes. With the 3D electronic models now being used and automated electronic measurement equipment accuracy is much improved and less tinkering is required in production.

The bottom line is that a pattern saves a lot of time when it comes to duplicating parts.