One Eleven question

TobyV · Post by **TobyV** » 04 Oct 2006, 21:52

Does anyone know why, when unpainted, the fuselage skin panels immediately adjacent to to the wings such a much higher quality finish than the rest of the airframe? :think:

See pic http://www.airliners.net/open.file/0220696/L/

Its not just teh AA jets, I have a b&w pic of G-ASYD as it first flew and thats the same :think: Was the manufacturing process different for this panel, e.g. milled-from-the-solid? :think:

Post by **Garry Russell** » 04 Oct 2006, 22:19

Hi Toby

The metal was different in that area and the manufacturing process left it with a dull finish that could not be polished.

This was a problem for American so that area was covered in metal foil to blend in nicely with the overall shine

Unfortunately the aircraft quickly dulled but not the foil leaving that appearance.

Garry

TobyV · Post by **TobyV** » 04 Oct 2006, 22:31

Thanks Garry, thats cleared that one up, might have guessed you'd know the answer

Post by **Garry Russell** » 04 Oct 2006, 22:37

In fact Toby the whole natural metal thing was a special order

BOAC and BUA were polished bottoms then but the 1-11 and VC 10 were grey

On the line they were a yellowish green en naturelle

Quebecair and US Air stripped their 1-11's but mostly natural metal bottoms were rare unless the aircraft was ex American

G-ASYD was in American basic at first and G-ASYE was built with a polished bottom.....but it was not the norm.

Garry

cstorey · Post by **cstorey** » 05 Oct 2006, 11:18

The yellow green is not natural - it is zinc chromate primer!

Post by **Garry Russell** » 05 Oct 2006, 11:26

I know it's not naturel for the metal as such

What I mean is the unpainted aircraft on the line is that colour that is the natural colour of the assembled aircraft after the part have been treated ready for assembly. I read about the pre assembly trestments they went through and finally beinf coated with the primer.

So the natural colour of the One-Eleven not the metal.

VC10 · Post by **VC10** » 06 Oct 2006, 17:24

The answer is the skin panels in that area were machined from billets

To quote from an article in 'Aircraft Engineering' - May 1963 about the One -Eleven -

"This region is heavily loaded in shear and needs considerable stiffener support, and if full advantage is to be taken of the furnishing line for the frames, the stringers are discontinuous. By machining the stringers & skin from solid, in the same way as the wing, a considerable reduction is made in the number of parts and in the assembly time in this area."

Paul