# Half Scale B-25

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#### vhhjr

HBA Supporter
It was for sale a while back for $240K. It's probably a bargain considering the time spent building it. Replacing the Hirths with Valach radials would make for a very interesting airplane. Just don't let Valach know what you're doing or they probably won't sell engines to you. Verner quit making their smaller radials and they might have been too big anyway. Another possibility would be to round up four Lawrance radials. They are the right size and put out similar HP to the direct drive Hirths. Vince Homer #### Bill-Higdon ##### Well-Known Member It was for sale a while back for$240K. It's probably a bargain considering the time spent building it. Replacing the Hirths with Valach radials would make for a very interesting airplane. Just don't let Valach know what you're doing or they probably won't sell engines to you. Verner quit making their smaller radials and they might have been too big anyway. Another possibility would be to round up four Lawrance radials. They are the right size and put out similar HP to the direct drive Hirths.

Vince Homer
I haven't seen Vince's B-25 but from what I saw of the Me-262 it should be good, and beats my idea of taking a set of Mini-Coupe plans rotate the fuselage section with the wing so the wing is on top & go from there. Would be more like a looks good from 200 yards after a bottle or 2 of Mad Dog 2020 than what Vince is doing

#### vhhjr

##### Well-Known Member
HBA Supporter
Bill,

Next time you're in town stop by and I'll give you a tour.

In a day or so I will start covering one side. I'm going to leave the other side in frame only.

Vince Homer

#### vhhjr

##### Well-Known Member
HBA Supporter
As promised here's a little write-up and some photos of the B-25 mock-up project. The project was started about a month ago and I worked on it some every day. I doubt I have more than \$200 invested in the project. These things are reasonably low cost fun.

Now I have to decide what to do with it. My other two fuselage mock-ups are hanging from the ceiling of my hangar. I think the B-25 will be mounted like it's flying through the West wall. Maybe I need to build the first 2 feet of the right engine nacelle......

Vince Homer

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#### BJC

##### Well-Known Member
HBA Supporter
Looks like you had a good time building them.

Sell them to a themed restaurant?

BJC

#### Riggerrob

##### Well-Known Member
UUUUUU!
UUUUUU!
Shiny!
Shiny!
Mighty shiny replica!
If you hang those on a restaurant wall, the ultimate installation would include hatches through the wall, spinning propellers, flashing lights in gun barrels and a full sound system!

Thanks for including drawings of anthropomen and comparison charts to inspire the rest of us.
Now I have to dig out my B&V 141, half-scale replica sketches .......

#### vhhjr

##### Well-Known Member
HBA Supporter
Here's a couple more photos of the B-25 and my hangar. Can you imagine, my wife suggests that I have to many projects!

Vince Homer

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#### Bill-Higdon

##### Well-Known Member
Here's a couple more photos of the B-25 and my hangar. Can you imagine, my wife suggests that I have to many projects!

Vince Homer
Keeps you "off the streets & out of the Pool halls" !

#### vhhjr

##### Well-Known Member
HBA Supporter
It's finished. Here's a few photos of the project. The scale at 50% is about right. That's going to make the wing span about 33 feet. You could go a little smaller, say 45%, but you would still have to make the engine nacelles at least 30 inches to accommodate either Verner or Rotec radials should authenticity be a goal.

I recommend this approach to anyone thinking of scaling down an aircraft. The 55% ME-262 that I made looked doable on paper, but when the mockup was finished it was obviously too small if you were bigger than 5' 6" tall and 150 lbs. I may need to make some fatter pilot templates. To be a true test the mockup only has to be correct in size. One doesn't have to get as carried away as I seem to like to do with all the extra details.

Vince Homer

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#### ScaleBirdsScott

##### Well-Known Member
A 1/2 scale B-25 would be a really cool project to see to completion. A 1/2 scale B-anything would be really fun.

I really like the energy going on with the mockup. Seems like it would make a fun cockpit to sit in with a few projector screens and some Flight Sim.

Looking over the numbers in that document, looks like the 63% with 2x Verner 9 cylinders would be how I would go. Plenty of room for the cockpit to feel "Bomberly" with 37" of width. And with the instrument panel designed properly have some nice forward vis.

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#### Tiger Tim

##### Well-Known Member
A 1/2 scale B-anything would be really fun.
It just occurred to me that a scale A-26 could be done with the wings, tail, and a lot of little stuff from an Aero Commander...

#### vhhjr

##### Well-Known Member
HBA Supporter
I looked at the A-26 and it's fuselage is thinner than the B-25, That would be OK as long as the nose wheel doesn't retract under the pilots.

A 63% B-25 would be big enough to put a person or two behind the wing as long as the CG stayed in limits. I think there would also be room to access the aft section over the wing spar. The A-26 solves that problem with an STC for installing a heavy duty ring spar/bulkhead to eliminate the flat thru spar. Yes, Aero Commander part might work and would save a lot of build time. Truth is I have seen many older Aero Commanders sitting with weeds over the tires. Might get on cheap. Also at 63% you might be able to use the Russian/Czech radials and props.

Vince Homer

#### Tiger Tim

##### Well-Known Member
Yes, Aero Commander part might work and would save a lot of build time.
What I find oddly satisfying is that not only does the Aero Commander have roughly the same planform as the A-26, it was designed by the same guy.

#### Riggerrob

##### Well-Known Member
Dear Vince Homer,
You cannot crawl over the wing inside a full-scale B-25.
I tried back when I weighed 190 pounds.
The tail-gunner's seat gives the best view during landings and take-offs.

In other news, I have contemplated using an Aero Commander as the basis for a stand-off scale DH Mosquito.

#### vhhjr

##### Well-Known Member
HBA Supporter
Since I have never tried to crawl over the wing I will defer to your experience. I was going by a diagram in the Pilot Training Manual for the B-25 where it shows doing just that as an option for emergency egress.. One needs to keep in mind that these planes were designed for average 20 year old crew members in 1942. I have a photo on my office wall of my Dad's 1943 Bomber school class taken in front of a B-25. He was 6 feet tall and weighed 150 lbs. I'm 5' 10" and weigh 200 lbs. The fruits of modern living.

Another example of this is I sat in a P-39 in an Australian Beck Museum and it was quite roomy and with a thin cushion could have been in flying position. The difference is that the seat was designed for a seat-pack parachute and I didn't have one. I'm told the average Russian P-39 pilot was less than 5' 9" and small stature.

#### Riggerrob

##### Well-Known Member
Seat parachutevcontainers vary in thickness from 2 inches to infinity.
Military parachute canopies (e.g. 28 foot diameter C-9) usually require a container 6 inches thick.
Seat cushions vary from almost nothing (competition aerobatics) to thick survival kits containing floatation, sleeping bag, etc.
Warbird pilots tend to prefer seat cushions 4 inches thick for "gentlemenly" formation flying ... that is on top of the 6 inch container.

#### BJC

##### Well-Known Member
HBA Supporter
Seat parachutevcontainers vary in thickness from 2 inches to infinity.
... and they all are uncomfortable.

BJC

#### vhhjr

##### Well-Known Member
HBA Supporter
A couple more photos of the finished B-25.

Vince Homer

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