North American Aviation NA-98X "Super Strafer" - Improved B-25H w/ R2800s

[Sturgeon]

Pretty sweet article on a very obscure plane.

 

Picture of the original concept:

[AdmiralTheisman]

This is sort of only tangentially related, basing on this being one of the strafing bombers, but why were the twin engined strafing bombers of the A-20/A-26/B-25 types either successful or at least viewed as so successful in their roles? It seems as if having a twin-engined bomber doing work like that would be inefficient and they would be less effective in providing strafing interdiction and close air support than fighter and fighter-bomber aircraft. True, they had more machine guns, but surely the 6-8 machine guns of the average American fighter were sufficient for ground tasks, and having 12+ is reaching the point of diminishing returns? Or were their advantages stemming from greater structural strength enabling more sustained support operations, longer loiter times and more range due to more fuel, more eyes observing targets on the ground, greater capacity of ammunition, or reluctance of fighter pilots to engage in ground support operations? Or just greater general capacity, in that they would be able to bomb targets, but also be able to conduct prolonged strafing missions afterwards, and thus the addition of forward-firing machine guns simply represented an expansion of their general capabilities, without significant opportunity cost?

[Sturgeon]

One of the advantages of the twins was infinite zero range, because all the guns were mounted close together in the nose. This allowed maximum saturation of the target during strafing runs, which was very helpful.

[xthetenth]

Also, part of it is that a bomber with a strafing nose is a bomber with the added capability to fire at any AA to try and suppress it. Great for maritime interdiction for instance. Then it's just a matter of how much weight you're willing to put into effectiveness, because every gun is buying a bit more saturation.

 

The Pacific saw some pretty major use of them (as well as rockets and futile attempts to get enough accuracy with a 75mm gun to get more range), so flight radius is a big factor.

[Jeeps_Guns_Tanks]

Another factor, since the strafers were invented by the 5th Air Force in the South Pacific, and they did it because trying to hit a ship with bombs from high altitude was really hard. They came up with the skip bombing thing, and added machine guns because they helped AA suppression and .50s mess up cargo ships and barges and other soft stuff like aircraft mechanics. They also did it to come up with new uses for bombers that sucked at level bombing, that were also the only bombers they could get, since they did not get priority on the good equipment. General Kenney, the commander of the 5th, had to fly to washington several times and beg for more B-24s and P-38s.

 

While this was going on, the 5th air force needed its fighters to be fighters, to take on the Japanese army's air force, and they had P-39, P-40s and a handful of P-38s, not enough for them to do much ground attack work.  The strafers worked so well though, and skip bombing actually hit ships, they eventually factory built various models, though I've heard mixed things on the 75mm armed version of the B-25.  

[Collimatrix]

I had heard that hitting anything with the big cannon whilst in fight was difficult.

 

I wonder if the concept would have any merit given the magic of modern fire control.

 

Apparently there was also a proposal to make the 75mm an autoloader:

 

 

A prototype existed:

 

[AdmiralTheisman]

Thanks for the responses to my query, it clears up why they were used instead of single engine fighters. The concept makes sense, even if I still find the idea of a 6-person and rather big medium bomber conducting strafing attacks like that rather funny. 

[Belesarius]

IIRC B-26s in similar configuration were used as COIN aircraft in Africa in the early 60s, against the Simba rebels in the Congo. There were B-26s that had as many as 14 .50 cals.

[Meplat]

Beech offered a version of the D-18/C45/SNJ with a much narrowed fuselage and heavy forward armament May have still ran the '985's or perhaps a pair of 1340's.

 

 But- With 2800's in lieu of the 985's?

 

Let's just say I have seen a C-45 pull vertical at max payload.  Had two PT6A's in place of the 985's.

 

The airframe was definitely robust enough, center spar AD notwithstanding. There is very little about a "twin bitch" that is fragile.