Scratch Build of B-17G 43-38083 "Happy Valley Express"

[FoCoB17G]

Latest update on the CAD model, here are several images. I've been working on the cockpit and related.

[cptsmith]

The navigators/bombardier compartment BLK 1-3 is a sub assembly, the forward fuselage BLK 1-6 is a major assembly. The B-17 SRM shows the breakdown. It also shows the part and BAC numbers needed for the sub assemblies.

[FoCoB17G]

The navigators/bombardier compartment BLK 1-3 is a sub assembly, the forward fuselage BLK 1-6 is a major assembly. The B-17 SRM shows the breakdown. It also shows the part and BAC numbers needed for the sub assemblies.

I have not encountered any subassemblies of 1-3. There are subassemblies specific to that part of the fuselage, as with all other areas, such as floor installations, instrument mounts, etc, all under the major subassembly 55-7330 (forward fuselage).

[cptsmith]

In the E & M Instructions the major assemblies are shown on page 55 and the sub assemblies are on page 56. All the forward sub assemblies make up the forward fuselage assembly (55-7330).

[FoCoB17G]

In the E & M Instructions the major assemblies are shown on page 55 and the sub assemblies are on page 56. All the forward sub assemblies make up the forward fuselage assembly (55-7330).

Oh! Alright, I see what you were talking about.

I beleive those are for maintenance and repairs? More or less making it quick and easy to find parts or assemblies that need to be fixed without having to dive through the maze of microfilm. The aircraft isn't actually built that way from my understanding. It may have been, but recalling pictures from the factory I'm not sure. In any case, it certainly wasn't drafted in those categories, and none of the drawings reference them at all.

[cptsmith]

Thats the way they were constructed towards the end of the run, not sure about the initial process. The SRM has some pics of the sub assemblies and I have seen pics of the radio room sub sections being built. All the forward sub assemblies were combined in a fixture and skinned with the cockpit enclosure being added later.

[cptsmith]

Here is a photo that shows bomb bay sub sections.

[FoCoB17G]

Very interesting! I haven't worked much on the model for horizontal stiffeners yet, I had assumed that they ran between major assemblies as specified in the instructions, "overlapping" for extra strength. From what I can see of the bomb bay sections that might not be the case? I'll try to pull up the drawings when I have a chance to dig through them.

[cvairwerks]

Usually for high rate production, section joints were simple bolt or rivet bulkhead face to face, or skin to bulkhead joints. With smaller aircraft, having a longeron lap joint is possible, but it does make the mating much harder than a face joint, or skin overlap.

While this video is for the B-24, it does give a decent idea about how production ran: https://www.youtube.com/watch?v=p2zukteYbGQ

[FoCoB17G]

I think it's time for another update on my work so far for the B-17. My new short term plan is to build a complete cockpit, and use it as a simulator. I think it would be a great opportunity to go around to local airshows and connect people with this history. I haven't gone too far down that path yet, but I am working on castings for the cockpit, and assembling a panel.

[FoCoB17G]

I've finished making 4 sets of 41-9804 "Aileron Chain Guard" out of 356 aluminum.

They will eventually be treated to T6, and machined to become 41-9817. I made a post elsewhere if anyone is in need of these impossible to find and hard to make parts.

Just another step towards the cockpit!