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The B-17 was originally designed for attacking ships at sea...this was because the USAAC envisioned that any enemy attacking the U.S. had to come by sea, so the B-17 was designed with that in mind.
So the B-17 had the ability both in range and warload to conduct maritime duties and the USN did in fact, have several B-17s serve in that role as the PB-1.
But the B-17 was in high demand from the USAAF, and the B-17 was only being manufactured at three plants: Boeing Seattle, Douglas Long Beach and Vega Burbank, where the B-24 was being manufactured in larger numbers from more plants: Consolidated San Diego, Consolidated Ft. Worth, Ford Willow Run, North American Dallas and Douglas Tulsa.
Why did the built it that way? We need to ask Magruder.
It may be the operational requirements from the USAAC/F.
The term "medium bomber" seems to have meant a bomber that operates at medium altitudes, not a bomber with a mid-range bomb load. That would mean that turbos or 2 speed superchargers were not required.
btw there was a proposed version of the B-26 with V-3420s. That would have been interesting to see.
I'm curious as to why that would be a requirement? I could understand the idea of carrying people in the bomb-bay -- the British had that in several bombers as a way of carrying troops (it would also carry more than just 2 guys)Fuselage also included an extra crew compartment for two men seating side a side, with passage between them, the compartment being located between pilots' compartment and bomb bay.
As for the wing, we have several things that matter when bombers are in question
How would it compare with the B-25?However, there wing airfoil choosen does not show any low drag vs. lift properties that one will need for a fast and heavy A/C.
As long as it fits, and bonus points if it get good ram, lolI'd put the intercoolers in front of leading edge of the wing.
Sorry about thatDon't mix supercharger stages with speeds - 2-speed S/C was always on R-2800s of the B-26s, 2-stage was never.
Wow that's fast...The greatest improvement in speed would've came at high altitudes, say above 20000 ft, probably comfortably above 350 mph
I was under the impression that they didn't want the twin-stage supercharger because it wasn't available in quantity in 1940. I'm curious if the turbocharged R-2800 was available any quicker?Martin (company) came out with plenty different engine set-ups for their Model 179, some inculding two-stage supercharged R-2600 or R-2800, and some including turboed R-2600, R-2800 and even R-3350.
What were the specifications that gave birth to the aircraft?It may be the operational requirements from the USAAC/F
Are you serious? Last I checked, a medium-bomber was generally an aircraft with a medium-ranged bomb-load that could be carried over a medium-distance.The term "medium bomber" seems to have meant a bomber that operates at medium altitudes
The aircraft's fuselage did have very nice, clean lines -- very good attention to detail it seemed. I was genuinely surprised about the wings.
- I never knew they used a symmetrical airfoil, the only conceivable benefits I could find with such an airfoil
- Flying inverted: Not really applicable as the design had a Norden bomb-sight which would suffer a gyro-precession as little as 18-degrees of bank
- Dive-Bombing: I don't recall the aircraft ever built for this purpose
- I figure the decision to keep the wing-span/area small was to decrease drag for high-speed. It certainly had low-speed penalties
- The lack of Fowler-flaps is a surprise, as it would have greatly increased the ability of the aircraft to fly at low-speed. The only thing I could think of would be that it might weigh more than the plain-flap.
- The wings were 15% thickness to chord?
How would it compare with the B-25?
I was under the impression that they didn't want the twin-stage supercharger because it wasn't available in quantity in 1940. I'm curious if the turbocharged R-2800 was available any quicker?
Why would you not have any seats in the nose where the bombardier would sit?With the B-26, in order to get to the nose compartment the coplilot had to move his seat back out of the way. There were no seats in the nose compartment, although the bombardier rode there. The navigator had his desk aft of the pilot's seat, but after takeoff he went down to the nose so he could argue with the bombardier over where they were. The nose compartment offered a much better view than did the navigator's compartment.
Now that is a major problem...In order to use the nose gun the Norden bombsight had to be removed.
What was the typical figures for the A-20 and B-25?On B-26, 17% TtC at root, same for B-25, that used the 5-digit NACA 230 series.
The twin-staged R-2800, however was available in small numbers, which makes it more of a sure thing...Turbo + R-2800 was also not a done deal in 1940.
The twin-staged R-2800, however was available in small numbers, which makes it more of a sure thing...
The bombardier sat on the spare ammo canister. The bombsight swung out of the way. Navigators often hung out behind the pilots watching over their shoulders.With the B-26, in order to get to the nose compartment the coplilot had to move his seat back out of the way. There were no seats in the nose compartment, although the bombardier rode there. The navigator had his desk aft of the pilot's seat, but after takeoff he went down to the nose so he could argue with the bombardier over where they were. The nose compartment offered a much better view than did the navigator's compartment.
As to why the B-25 used a bomb/nav and the B-26 had two separate crewmen for those tasks, I have no idea. I guess that is a vote toward the "smaller 4 engined bomber" idea.
In order to use the nose gun the Norden bombsight had to be removed. I do not think this was the case for the B-25.
And, finally, the B-25 was better because one of my high school teachers was bomb/nav on them, starting his combat career aboard Plane No. 10 from the USS Hornet.
The B-26 beat the B-25 to the Pacific because the 22nd BG had a full complement of B-26s and was considered fully operational when the war broke out. Technically, the B-25 did beat the B-26 to Australia, several had been ferried to the Dutch, but the loss of the NEI meant they were stuck in Australia while the crews trained up on them. Many of these were then traded back to the USAAF to equip two squadrons of the 3rd BG (Light). B-26s were deployed to Alaska in January 1942. B-26 production actually was ahead of B-25 production at this time because the Martin did not make any major changes to the initial production batch of B-26 MAs, whereas North American changed the B-25 several times before the introduction of the B-25C, the first combat capable model, was introduced.I have not heard it explained why the 26 beat the 25 to the Pacific but then was replaced by the 25 there and was relegated to a bit in the Med and the ET where the 25 also served. The 25 also served in the Med and ETO. I know of no mi than the 25,ssion where the 26 proved to be better tihan the 25, but clearly there were those that the 25 was superior, including as a trainer. Some B-26 units were transitioned to the A-26 in the ETO.
And the Ventura and PV-1 are much more like the B-26 than the B-25.
True enough, but I'm still surprised they didn't see high-altitude capability as being more useful. What road-blocks affected twin-stage supercharger set-ups in the United States? I know as a general rule the USAAC favored turbochargers almost without fail, but I'm curious if it would have hurt them to have given twin-stage supercharging a whack before the Merlin...wuzak said:Small numbers doesn't make it more of a sure thing
Structural strength means like g-load?Greg Boeser said:The why didn't they use fowler flaps, different wing etc. on B-26 is simple. The Martin Co. asked what the overriding requirements for the contract were and was told: speed, bombload, structural strength. Low speed handling was not addressed, so they ignored it.
So it could be quickly swung back into position and used?The bombardier sat on the spare ammo canister. The bombsight swung out of the way.
I thought somebody stated that the B-25's switched to the bombardier/navigator systemInitially, both the B-26 and B-25 had bombardiers and navigators. The bombardier was often an enlisted man. As the war progressed and individual aiming gave way to formation bombing the bombardier and navigator duties were usually carried out by a single individual (togglier). Only lead planes carried a lead bombardier and lead navigator, generally the most skilled in the unit.
Wasn't it a requirement of bombers designed pre war and early war to be able to carry troops as a secondary requirement?The British had a way of carrying several troops in the bomb bays of (British) bombers ???
The only British bomber I know of that could do this, or did do this, was the Mosquito, which, on the 'ball bearing run' from Sweden to Scotland, could carry one person, on a hammock-like arrangement, in the bomb bay - very cold and uncomfortable.
Seems they were going for the RAF idea...An attempt was made with the B-26C-6 to eliminate the co-pilot, but these were converted back to standard configuration in the field.
The RAF did seem to have this as a requirement on at least some of the bomber specificationsWasn't it a requirement of bombers designed pre war and early war to be able to carry troops as a secondary requirement?
Seems like a useless arrangementMIflyer said:In the book I read, the only time they used the nose gun the bomb took it off and handed it to the nav, who, having no place to sit, squatted there and held it while the bomb blazed away.
I was under the impression (and I could be wrong) that as originally intended, attack aircraft were tactical bombers, and bombers were strategic bombers. For some particular reason I'm not entirely sure of, the B-25 and B-26 were classified as bombers.The XB-28 was a high altitude medium. They built one and cancelled it. By late in WWII they realized that the main value of mediums was in low altitude attacks.