Wartime Aluminum Extrusions

[Stressmerchant]

Hi

First post, hoping that someone out there will be able to help me with this query.

I'm working on a vintage PBY Catalina aircraft. Some of the design drawings call out aluminum extrusions that have an identifier I haven't seen before. The Structural Repair Manual includes a table of materials that refers to various Alcoa sections, and gives their dimensions. These are typically sections such as K11271, K78F, 1288, etc

However, on some drawings (particularly fuselage areas), there are references to extrusions such as Y2A-44T and Y6A-26T. These sections do not appear in the SRM at all. To add to the confusion, some drawings have different formats for the section identifier; I have seen (eg) Y2A-44T, Y2-A-44(t), etc.

Most of my work is done on C47 / DC-3 types. I have checked the the various Douglas documents on extrusions, since they often supply the Douglas number and the ALCOA die number. No luck.

Does anyone know where these sections came from, and what the section properties were? If I can identify the properties, I can specify a modern equivalent for the work.

 

[MikeHalloran]

You need a cross reference to Consolidated, not Douglas, part numbers.
Sorry, I don't have such a thing.

A Google search on <"PBY" extrusions> was _slightly_ productive, in finding a few actual extrusions offered.

Scribd came up with a PBY5 SRM, in which reference is made to a 'section VIII', where one might find equivalent built-up sections for unavailable extrusions. Unfortunately, the document does not include a section VIII.



Mike Halloran
Pembroke Pines, FL, USA

 

[MiketheEngineer]

You might check with some restorers - such as the Confederate Air Force out of Harlingen, TX or even the Smithsonian!! They have restored many such aircraft.

 

[epeus]

I would head down the direction that MiketheEngineer mentioned, check out others who have restored these aircraft, I am not sure what country your in but the first place I would contact for info about the catalinas would be the Historical Aircraft Restoration Society Inc (HARS)(see

http://www.hars.org.au/

for contact details) in australia, they have restored this particular aircraft and its regularly belting around the skies. There is another in the process of being retsored at Bankstown aircraft, from memory its the Catalina Flying Memorial who are doing this one, however I don't think they are doing much major structural repair at this point, but you never know they may have some info. see

http://www.catalinaflying.org.au/

for contact details.

hth.

 

[Stressmerchant]

Hi

Thanks for the responses, have emailed the various restorers.

I have the SRM for the aircraft, including section VIII. Unfortunately it doesn't include the extrusions I am looking for. I do find it a bit odd - the original drawings call out these extrusions, but the SRM does not include them in the list of repair materials (Appendix 1), or equivalent built up sections (Section VIII).

My reference to the Douglas parts was simply because many manufacturers sourced their components from a a common source - typically ALCOA or Bohn for extrusions. Douglas have their own part numbering system, but the Douglas drawings often give the ALCOA number as well. I had been hoping that if I waded through the Douglas drawings, I would find a reference to the "Y" numbers I was looking for. Sadly no luck.

Consolidated tended to refer directly to the ALCOA numbers for their extrusion numbers. I have emailed ALCOA, but had no reply.

Thanks for the help, let's hope someone at the various restorers has some insight.
Regards

 

[debodine]

I would also consider checking out the USAF Museum at this web address:

http://www.nationalmuseum.af.mil/

There are a lot of links at that site and one or two might lead you to some restoration or research folks.

And also consider checking out the Wright B Flyer restoration organization at this web address:

http://www.wright-b-flyer.org/

The USAF Museum has decades of experience at restoring older military aircraft. The Wright B Flyer organization of course won't be focused on the aircraft you are working, but the members of the Wright B Flyer organization are mostly retired officers with very good connections to the people at the USAF Museum. Many years ago when I met a couple of members they turned out to be retired general officers, and you know they have connections.

If someone from the Wright B Flyer organization was able to put you in contact with a specific person in the museum you might find what you need.

 

[GregLocock]

When you find the section dimensions bear in mind the cost for an aluminum extrusion die is remarkably cheap - of the order of $2000.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[Jonpark]

If you have the section dimensions have a look at the Castle metal extrusion catalog here for the next closest shape. You can search by shape as well.

http://www.amcastle.com/Aerospace/login.aspx