Prewar door replacement

[shipljl]

My 41 came to me with aluminum sheet metal doors that somewhere in the past replaced the original wood doors (no logbook entry). My mechanic is concerned about the legal use of these doors. I thought about making new wood ones but that's more than I want to take on right now. Any advice? What has been done in the past? Can I do a 337 for the existing aluminum doors?

[Hank Jarrett]

Re: Prewar door replacement

I have some drawings for the wood ones. Are you a master wood worker? They are works of art and NOT something the average shed builder is going to make. Maybe someone else knows for sure but I would think a simple log entry showing replacement of the early part number doors with the later metal ones would be enough as long as the hinges and latches are solid and the doors fit the new frames (the opening is different for the early and late doors so whoever replaced them had to make new frames too.
I would bet if you look closely you may not have a 41 fuselage. If the original was damaged somewhere back in "pre-history" (didn't make it to the log books), it could have been replaced with a post war one.
Hank

[shipljl]

Re: Prewar door replacement

Thanks Hank, I already have a copy of your drawings and after reviewing both the effort and the cost decided to use the existing aluminum doors for now, but my mechanic is concerned about legality.

[Larry Lyons]

Re: Prewar door replacement

My 41 Deluxe has the aluminum doors, I would have to look on the FAA CD to see if there is an entry. Or if you like wait and see how many log in here and say the they have the aluminum doors too. As I am not that sharp at looking for details like this, it may take me a day or two but I will look on my CD. By the way, Airventure is coming up and you can get your CD free from the FAA if you apply at their tent there. Larry

PS: My bird was owned and flown by a A&P/I for well over 40 years and his son an A&P/I soloed in this bird aobut 50 years ago. It has had the aluminum doors ever since he bought it!

[Hank Jarrett]

Re: Prewar door replacement

Seems like the first time someone slams the wood door with anything in the way above the base of the window it breaks the wood frame. It wouldn't surprise me at all that lots of the wood doors were changed out long ago. That said, I love the feel and sound when you close the wood door. It just "feels right".
I am still messing with trying to get Josh's plane restored back here so if anyone is willing, I would like to get a copy of the CD on his plane. There are a LOT of questions and I won't be able to make AirVenture again this year.
Hank

[NC36061]

Re: Prewar door replacement

MANY airplanes have had doors changed over the years, they are all B models built under the same ATC; I don't believe the TCDS says anything about the construction of the doors, so any door should be acceptable. If you have a BC12-65 Deluxe, wood doors were original, but if those were replaced with any other type of door used on other B models, your mechanic shouldn't be concerned. I think he just needs to be to be educated; pre-war doors were welded tube construction, 12-65 Deluxes had wooden doors, early post-war used welded tube slightly different from pre-war, later post-war switched to the aluminum doors. Any door on any B might not be historically correct, but certainly not something to worry about from an airworthiness standpoint.

[astjp2]

Re: Prewar door replacement

The door tube cross section is roll formed J, you can still get it, just need to order 1500.00 worth at a time. Tim

[Hank Jarrett]

Re: Prewar door replacement

I have some tube doors we could use to build a fixture if anyone wants to make them. They are for my 45 so I won't sell them, but they are clean straight uncovered doors that would be perfect for laying out a fixture. With $1,500 worth of "J" tube we could make a batch of tube doors for several planes. I have a GREAT welder nearby who would probably be interested in building them.
Hank

[astjp2]

Re: Prewar door replacement

That sounds great Hank, you can start your AS9100 paperwork now along with your STC application, and your Quality control Manual, when you get it done in 2- 5 years and MIDO approves the process, then someone might have the capital they are willing to invest. You would have to have every door sold before production to meet 91.303b2 and the owner would have to give you a letter approving the design for an owner produced part.

This is why I neer finished my fuel valve stc....I could if I wanted to invest the time to write 200 pages of technincal stuff and get tooling fixtures manufactured to ensure each one is exactly built the same as the others. I thought the price of 125.00 was ok, but I took a loss on every one and some people wanted to reinvent the wheel and get a race car valve installed or one off of another airplane. Tim

[Hank Jarrett]

Re: Prewar door replacement

Yea, the only way to REALLY do it is to build the doors in a way to use the owner produced parts path. We have done this before and it IS possible, but you need the feds to approve of what you are doing as part of the start up process. I think it might be a little easier with the doors since they are not primary structure and we have few customers who could be closely involved in making them.
It CAN be done, but the STC or approved manufacturer path isn't worth it for so few parts. See, we SHOULD have bought the factory when we had the chance! We need to NOT miss the next opportunity. The Mexican investors who hold it now should get tired of it some day. They are sure not going to build airplanes.
Hank

[stearman3]

Re: Prewar door replacement

Don't even bother with the Feds. Most of 'em won't know what they are looking at.
Just do it,and like Elmer Fudd says," SHHHH Be vewy,vewy quiet!"

[astjp2]

Re: Prewar door replacement

That is good for a one off fix, but if someone is to invest 1000.00 in tooling and materials, you wont be able to advertise or even let people know you have it available and if the feds catch you making it before the owner requests it, you are hosed! Tim

[Hank Jarrett]

Re: Prewar door replacement

Short run fixtures won't be nearly that expensive. I would envision wood fixtures to hold the tube for tacking the pieces together and final weld in the open, followed by putting the door back in the fixture to "encourage it" into alignment. The tube doors are not that hard to bend to match the door openings.

With only a few doors to build we would want to get the people involved together to share the design, build, QA and documentation process so all could claim "owner built".

Not easy, but not that hard. I have built a LOT of parts for my plane from scratch. The first one is tough, the second through tenth are usually easy.

Hank

Lot easier if we owned the TC. Then whenever someone made a part we could look at it as an investment for the future of all Taylorcrafts. Nothing wrong with starting that process now.