Hangar Thirteen Foundation

05/25/2026

Today is Memorial Day.

This is not just a holiday - it's why we do what we do.

We must never forget.

05/23/2026

05/20/2026

05/12/2026

The electric motor for Boeing B-17F Lucky Thirteen's ball turret is still not back from the shop, however...

The motor for the top turret IS here. And, we have just completed its restoration!

So, here is a video of Lucky Thirteen's top turret motor running live and ready for its transmissions. Just need one more Hobart transmission, and we can start working to find top turret gear boxes.

Hope you like the new format. The spark is funny - it only does that when I'm filming! Ha!

05/09/2026

Opinion question -

When we began work on the ball, I originally assumed the power conduit was stockinette-covered rubber, like the oxygen hoses. However, our recent trip to California afforded me the chance to see an original ball turret conduit up-close -

As you can see, that's not quite what it was. It was stiffer than an oxygen hose, with a hard vinyl-like texture.

I have been trying to find a match for this material. So far, the closest I can find online appears to be a radiator hose made by Dayco. But not having access to it in person, I'm not sure how appropriate a match it is.

Whatever the material used, the conduit must have a 1.25" inside diameter, with one section being 49" and the other 24" in length.

If a radiator hose like Dayco's is a match, it would have to be longer than the lengths they typically sell. I reached out to Dayco for details but they have not responded.

Looking up similar hoses has not been fruitful. PVC and silicone are popular these days, looking nothing like the wartime conduit.

Anyone have any thoughts on a matching hose material? Have any material on-hand that may be a match? Or have any of the Dayco hose long enough to try?

05/05/2026

Today we wanted to share a new addition to the Type A-2 Ball Turret we are rebuilding for Boeing B-17F "Lucky Thirteen" (42-3455, 384BG).

This is something we have been after for a long time - the Spare Parts Box.

(Stijn Claus, I think you'll get a kick out of this one...)

All four variants of the Sperry ball turret featured a parts box, though only the A-2 used this particular clip-on variant.

While this example is missing its lid, we are fortunate that it still has its wooden insert. Better still, it is a Briggs-made variant. (Since our ball is a Briggs, we are trying our best to have a matching-parts turret.)

The piece now restored and installed, the only bits missing are the lid and the pieces which go inside. Our friend Paul Schneider has already volunteered to recreate the missing lid. And while it may be silly, it would be nice to try and fill out the contents of the box too.

So, anyone up for a treasure hunt?

Fred the Turret Guy was kind enough to fill out the spare fuses for the Trouble Light, Suit Heater, Gunsight, and Gunfire/Cut-off circuits. So, that leaves:

- 2x 301-30P-24-28V Mazda Bulbs
- 2x Briggs 877/Emerson 205394 Slip Ring Retainers
- 2x Briggs 871/Emerson 205407 Brush Bars (5/16)
- 2x Briggs 869/Emerson 205410 Brush Bars (1/4)
- Briggs 1903/Emerson 206268 Door Check Wire Clip

And most importantly -

- 2x 125V/120A Cartridge Fuses (Littelfuse 1402, Army Spec 94-32272)

We have put out calls for machinist volunteers before (alongside our regular calls for fabricators) and got no replies. But we do have a friend with another group whose willing to look into making new brush bars for the turret, so filling out the spares would involve just making a few extra. The original bars from our housing were all damaged beyond repair from the crash.

The Slip Ring Retainers would involve finding additional examples of the octagonal pieces on the brush housing. Maybe someone has some wreckage?

But it is those 125V/120A fuses that are the real kicker - the turret cannot operate without them.

Fred has a few precious wartime originals which we could measure and photograph for reference. The odd thing is that the only modern versions we have found so far are larger than the originals. The originals were roughly 2.75" from pole to pole in length, about an inch shorter than modern examples. Maybe someone has some originals laying around?

One way or another, we are psyched to have this piece here. We love little details.

See photo descriptions for more.

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By the way, I realize that we normally do a month-long fundraiser for the month of May. We have all been working so hard that the month just kind of snuck up on us. So, maybe next month. But don't let that stop you from contributing if you want to see more progress!

https://hangarthirteen.org/donate/

04/26/2026

Ray sent a couple videos this morning, working in the shop.

04/24/2026

A big announcement for today...

We now have blueprints for the Sperry ball turret.

Here's the story:

After some extensive research and digging, the National Air and Space Museum, Smithsonian Institution was able to confirm with us that some drawings still exist. These were filed under Briggs, as Briggs was the original manufacturer for the turret, Sperry having only designed the ball.

Now, there are some limitations. Many drawings are missing and the Smithsonian still will not offer duplicate rolls, nor have they any digitization services. So, physical copies must be ordered, and only a certain number can be ordered at a time.

That said, with our own research thus far, we have managed to extensively document the evolution of the turret. And, with our work restoring the A-2 for "Lucky Thirteen," the only significant challenge before us on the ball is the shell itself.

Since it seems unlikely that anyone with an original ball (not attached to aircraft) will work with us, unless something changes, we will likely cast our own. Having 3D scanned an original A-2 already, these drawings will finally fill the last information gaps to make that happen.

Unless an original becomes available... ;)