Announcement

Collapse
No announcement yet.

WWII USAAF 4 engine redisign

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • WWII USAAF 4 engine redisign

    Consider for the moment, that the USAAF reconsidered Current designs of Long Range Bombers (LBRs) such that the 'waist gunnner' position is reconsidered in terms of an additional upper powered turret! ?

    The two waist gunner positions in both the B-17 and B-24 are replaced by a powered upper turret of twin 0.50" cal. to cover flanks and other aspects using one less 'gunner' but the same number of guns! ~ and field of fire! ...

    In the case of the B-17; optimal would have been the 'ball'/belly turret located about where the twin 'waispe' guns were located. This puts the upper twin turret just past the radio-operators station and in a position to support 'other guns' on covering the flanks of the Fortresses.

    In the case of the B-24, we are looking at the secondary upper turret be in the position of the two waist guns/gunners; with the ball turret as standard, giving full/normal 'field of fire' coverage.


    ANY Contray Comements ....
    TANSTAAFL = There Ain't No Such Thing As A Free Lunch
    “War is merely the continuation of politics by other means” - von Clausewitz
    Present Current Events are the Future's History

  • #2
    Originally posted by G David Bock View Post
    Consider for the moment, that the USAAF reconsidered Current designs of Long Range Bombers (LBRs) such that the 'waist gunnner' position is reconsidered in terms of an additional upper powered turret! ?

    The two waist gunner positions in both the B-17 and B-24 are replaced by a powered upper turret of twin 0.50" cal. to cover flanks and other aspects using one less 'gunner' but the same number of guns! ~ and field of fire! ...

    In the case of the B-17; optimal would have been the 'ball'/belly turret located about where the twin 'waispe' guns were located. This puts the upper twin turret just past the radio-operators station and in a position to support 'other guns' on covering the flanks of the Fortresses.

    In the case of the B-24, we are looking at the secondary upper turret be in the position of the two waist guns/gunners; with the ball turret as standard, giving full/normal 'field of fire' coverage.


    ANY Contray Comements ....
    One turrent with 2 guns can only fire in one direction. Two single guns have both flanks cover at the same time, something the dbl in a turrent could not do. How about dbl 50s in the waist on both sides?
    "Ask not what your country can do for you"

    Left wing, Right Wing same bird that they are killing.

    you’re entitled to your own opinion but not your own facts.

    Comment


    • #3
      Originally posted by G David Bock View Post
      Consider for the moment, that the USAAF reconsidered Current designs of Long Range Bombers (LBRs) such that the 'waist gunnner' position is reconsidered in terms of an additional upper powered turret! ?
      ......
      Good question!


      Think about weight distribution and drag. Key components in aircraft design. Turrets have both. Even the weight of the ammo was a factor.

      Also consider the arcs of fire. A belly or top turret can't hit targets above/below a certain elevation where the waist gunners are in their optimal gun elevation. Wings get in the way etc.

      The people that designed these planes were smart as hell and the B-17/B-24 proved itself time after time.


      Second guessing is a good exercise, and hind sight is 20/20, but I think "they" did what they did for good reasons that may not be obvious to us, after the fact observers.
      Battles are dangerous affairs... Wang Hsi

      Comment


      • #4
        Actually both the B-17 and B-24 had special "escort" versions developed specifically for what you have in mind. The B-17 version was the YB-40, the B-24 version was the XB-41. The XB-41 apparently even in the experimental version was a massive failure; the YB-40 versions actually made it to combat but was not deemed a success as they were so heavily loaded with extra weapons (another ball turret in radio position plus a nose turret and twin .50s at the waist) and ammo, they couldn't keep up with the standard B-17s so the standard B-17s ended up escorting the YB-40 back after the drop point. Nice idea but impractical in operation. The XB-41 had the same weapons layout.

        Comment


        • #5
          Originally posted by boomer400 View Post
          Actually both the B-17 and B-24 had special "escort" versions developed specifically for what you have in mind. The B-17 version was the YB-40, the B-24 version was the XB-41. The XB-41 apparently even in the experimental version was a massive failure; the YB-40 versions actually made it to combat but was not deemed a success as they were so heavily loaded with extra weapons (another ball turret in radio position plus a nose turret and twin .50s at the waist) and ammo, they couldn't keep up with the standard B-17s so the standard B-17s ended up escorting the YB-40 back after the drop point. Nice idea but impractical in operation. The XB-41 had the same weapons layout.
          The design of the YB-40 is partly what got me wondering on this. Also having just read "Masters of the Air"
          http://sites.lafayette.edu/millerd/o...rs-of-the-air/
          http://www.amazon.com/Masters-Air-Am.../dp/0743235452

          The 'chin turret' is one concept from the YB-40 that was fitted to standard production B-17s in the 'G' model. The B-17 went through some major design revisions in it's history, especially in the armaments area, as well as engine upgrades and the larger dorsal fin of the 'E' model onward.
          http://en.wikipedia.org/wiki/B-17_Flying_Fortress

          The waist gun positions had their own drag factor, until the openings were improved with better mounts and plexiglass enclosing, and also a constricted field of fire, along with upping the crew discomfort factor of the opening to colder temperatures. Replacing same with an upper turret designed to depress to cover both flanks would have reduced these drawbacks for slight gain in weight of the turret, partially offset by reduction of one crew-member. A slight modification to leading edge of the dorsal fin(tail) could have allowed placement of the second upper turret in the waist guns position.

          Admittedly, the new turret could only cover one side at a time, but their would be a gain in firepower and effectiveness that should compensate. Flank attacks were less common and if one one gun/gunner is responding, the defense is rather limited anyway. Note that the B-29 had no waist gun positions and turret design/placement was such as to cover for this. Also, RAF 4 engine bombers didn't have waist gun positions in their design.

          There is a trade-off factor here I'll admit. Radio operators gun (in B-17) is eliminated (limited effective anyway) by an additional turret covering the upper area, and one less gunner, so weight savings here partially offsets the turret weight. Which ever flank is covered on the side attacks is bringing two guns to bear rather than one, and in a mount better able to track and sustain coverage.
          TANSTAAFL = There Ain't No Such Thing As A Free Lunch
          “War is merely the continuation of politics by other means” - von Clausewitz
          Present Current Events are the Future's History

          Comment


          • #6
            well, USAAF probably wanted to have the YB-40s provide extra firepower all around without having to heavily reengineer the standard 17F airframe too much since that would mean a major production line change. The better alternative to weight reduction would have been to provide more powerful engines than the R1820s so they could keep up with the rest of the formation. Maybe turbo'ed R2500s might've been able to do the job. They did have an Allison turbo engined version (B-38) which might've been interesting if they could've ironed the bugs out. But all the Allisons were prioritized to fighters so that was a no go.
            Last edited by boomer400; 27 Oct 12, 17:12.

            Comment


            • #7
              The USN did do something sort of like that with the PB4Y Privateer. In that case they did away with the belly turret as the plane was intended for much lower alititude operation. The waist positions were put in large bulges and the guns doubled. A second top turret was added.

              Comment


              • #8
                Funny, I always thought that's what the B-29 was supposed to do.
                Indyref2 - still, "Yes."

                Comment


                • #9
                  Originally posted by the ace View Post
                  Funny, I always thought that's what the B-29 was supposed to do.
                  Bingo!

                  And as Miller points out, had USAAF strategic bombing not shown measurable gain by mid-1944, some B-29 formations might have been deployed to ETO.

                  As things developed, the decline of Luftwaffle fighters as a portion of German AD, in part due to long overdue long-ranged escort (primarily P-51s), made this option (and support complication of a third type LRB(Long-Ranged Bomber) to logistics equation) un-necessary.

                  Japan undoubtably was a less hostile environment to B-29 ops than the ETO could have been.
                  TANSTAAFL = There Ain't No Such Thing As A Free Lunch
                  “War is merely the continuation of politics by other means” - von Clausewitz
                  Present Current Events are the Future's History

                  Comment


                  • #10
                    Really, USAAC recognized the B-17/ B24 as being insufficient in the mid-late '30s which is why the B-29/B-32s came about. But since none of those a/c were available, they were forced to build up the B-17/B-24s. The gestation period of the B-29 was pretty long, from about '38 (concept-wise) to '44 (first combat missions); and they weren't the greatest planes to fly with those R-3350s burning up on takeoff. I maintain that better powerplant technology might've made more of a better difference than adding more guns....maybe over Europe that might've been different. Of course, the bombing strategies were different from theater to theate also.

                    Comment


                    • #11
                      Originally posted by boomer400 View Post
                      Really, USAAC recognized the B-17/ B24 as being insufficient in the mid-late '30s which is why the B-29/B-32s came about. But since none of those a/c were available, they were forced to build up the B-17/B-24s. The gestation period of the B-29 was pretty long, from about '38 (concept-wise) to '44 (first combat missions); and they weren't the greatest planes to fly with those R-3350s burning up on takeoff. I maintain that better powerplant technology might've made more of a better difference than adding more guns....maybe over Europe that might've been different. Of course, the bombing strategies were different from theater to theate also.

                      True the B-29 began as a pressurized cockpit high altitude bomber concept but didnt the main impetus for the B-29, XB-30, B-32, YB-35, and B-36 come from a USAAF request for a very long range bomber able to strike Euroean targets from non Continental Europe bases. Thus if England and whoever retreated to US and Canada could still strike at Axis targets.

                      Comment


                      • #12
                        Originally posted by boomer400 View Post
                        Really, USAAC recognized the B-17/ B24 as being insufficient in the mid-late '30s which is why the B-29/B-32s came about. But since none of those a/c were available, they were forced to build up the B-17/B-24s. The gestation period of the B-29 was pretty long, from about '38 (concept-wise) to '44 (first combat missions); and they weren't the greatest planes to fly with those R-3350s burning up on takeoff. I maintain that better powerplant technology might've made more of a better difference than adding more guns....maybe over Europe that might've been different. Of course, the bombing strategies were different from theater to theate also.
                        QUOTE:
                        Design and development


                        The length of the 141-foot (43 m) wing span of a Boeing B-29 Superfortress based at Davis-Monthan Field is vividly illustrated here with the cloud-topped Santa Catalina Mountains as a contrasting background.



                        YB-29 Superfortresses in flight.



                        A Superfortress returns from a training mission to its base at this Training Command B-29 Transition School.




                        Boeing began work on pressurized long-range bombers in 1938, when, in response to a United States Army Air Corps request, it produced a design study for the Model 334, a pressurized derivative of the Boeing B-17 Flying Fortress with nosewheel undercarriage. Although the Air Corps did not have money to pursue the design, Boeing continued development with its own funds as a private venture,[3] so that when, in December 1939, the Air Corps issued a formal specification for a so-called "superbomber", capable of delivering 20,000 lb (9,100 kg) of bombs to a target 2,667 mi (4,290 km) away and capable of flying at a speed of 400 mph (640 km/h), they formed a starting point for Boeing's response.[4]
                        Boeing submitted its Model 345 on 11 May 1940,[5] in competition with designs from Consolidated Aircraft (the Model 33, later to become the B-32),[6] Lockheed (the Lockheed XB-30),[7] and Douglas (the Douglas XB-31).[8] Douglas and Lockheed soon abandoned work on their projects, but Boeing received an order for two flying prototypes, given the designation XB-29, and an airframe for static testing on 24 August 1940, with the order being revised to add a third flying aircraft on 14 December. Consolidated continued to work on its Model 33 as it was seen by the Air Corps as a backup in case of problems with Boeing's design.[9] An initial production order for 14 service test aircraft and 250 production bombers was placed in May 1941,[10] this being increased to 500 aircraft in January 1942.[5] The B-29 featured a fuselage design with circular cross-section for strength. The need for pressurization in the cockpit area also led to the B-29 having the only "stepless" cockpit design, without a separate windscreen for the pilot, on an American combat aircraft of World War II.


                        http://en.wikipedia.org/wiki/B-29_Superfortress


                        Development


                        XB-24 in flight


                        The Liberator originated from a United States Army Air Corps (USAAC) request in 1938 for Consolidated to produce the B-17 under license. After company executives including President Reuben Fleet visited the Boeing factory in Seattle, Washington, Consolidated decided instead to submit a more modern design of its own.[7]
                        Specifications

                        The new Model 32 combined the Davis wing, a high efficiency airfoil design created by unorthodox means by a lone inventor named David Davis,[8] the twin tail design from the Consolidated Model 31 flying boat, and mated both together on a new fuselage. This new fuselage was intentionally designed around the twin bomb bays, each one being the same size and capacity of the B-17.
                        In January 1939, the USAAC, under Specification C-212, formally invited Consolidated[9] to submit a design study for a bomber with longer range, higher speed, and greater ceiling than the B-17. The specification was written such that the Model 32 would automatically be the winning design. The program was run under the umbrella group running "Project A", an Air Corps requirement for an intercontinental bomber that had been conceived in the mid-1930s. Although the B-24 did not meet Project A goals, it was a step in that direction. Project A led to the development of the Boeing B-29 and Consolidated's own B-32 and B-36.[10]


                        http://en.wikipedia.org/wiki/B-24_Liberator


                        Sounds more like about the late 30's the USAAF started looking for a 'next generation' bomber, but 'short-comings' didn't really show until both types had some combat experience.
                        TANSTAAFL = There Ain't No Such Thing As A Free Lunch
                        “War is merely the continuation of politics by other means” - von Clausewitz
                        Present Current Events are the Future's History

                        Comment


                        • #13
                          As I mentioned above, the idea for this thread come from reading Miller's book;
                          http://www.amazon.com/Masters-Air-Am.../dp/0743235452

                          He delves into the ideology of the "Bomber mafia"; Arnold, Spaatz, etc.; whom kept expecting that larger and longer raids would get through, and fighter escort wasn't needed. Even after the first few disasterous raids, and despite approving directives to build-up numbers of aircraft and units of fighter types to escort, such wasn't a top priority of the 'mafia', so the appearance of "little friends" took longer than it could have.

                          In looking over the losses in aircrew as well as aircraft by the 'bomber boys', along with what improvements were made;
                          1) chin turrets and replace .30 cal with .50 cal on the B-17s
                          2) power front turrets on the B-24s
                          Got me wondering if something else could have been done. I was aware of the lackluster performance of YB-40 and YB-41, and was thinking if they'd tried something a bit less extreme, such as I lay out in my first two posts here, perhaps these designs might have been more effective.
                          TANSTAAFL = There Ain't No Such Thing As A Free Lunch
                          “War is merely the continuation of politics by other means” - von Clausewitz
                          Present Current Events are the Future's History

                          Comment


                          • #14
                            If one examines the long and convoluted tale of the United States long range bomber program of the 20s and 30s (much less the entire concept of air power by the US), there are many branches of that process which spawned the operational B-17, 24, 32, 36, 50 piston engine heavy bombers (for that matter, the entire air war doctrine which was in constant evolution).

                            One thing to note, in 1933, the Project A specification for a 5000 mile range, 200mph bomber with a 1 ton bomb load resulted in Boeings XB-15; its inital design specification called for the Alllison V3420, an engine that was still a blueprint idea. Martin had the Model 145B twin boom design powered by standard V1710 Allisons, apparently that was a non-starter for the Air Corps for not even a prototype was built. Another thing to note from the Project A proposal was the specific inclusion for the use of the a/c in reinforcing Panama and Hawaii. Not so much for Europe. In fact, much of the '30s bomber doctrine revolved around coastal defence as the Joint Board was so politically enjoined for protecting each branches turf and claiming new turf through doctrinal modifications.

                            In any event, in 1934, USAAC requested a replacement for B-10; that resulted in the Boeing Model 299 with a first flight July 1935. The 299 eventually became the B-17 but only after much fiddling about. In fact, as of September 1939, about 12-13 B-17s had been delivered.
                            Meanwhile, in 1935 Project A combines with Project D = BLR (bomber long range) project; ie maximum range possible bomber resulting in actual XB-15 a/c (first flight October 1937 and powered by R-1830 radials) and the Douglas XB-19 (first flight June 1941 and the biggest Air Corps/Force a/c until the B-36!) Later, the XB-15 never a production system although it had useful testing purposes gets redesigned (but never made) as the Model 316 with pressurized cabin and various other modifications. Also, rejected as production system.

                            Later in 1938, the Kilner Board ups the ante and lays out requests for bombers with 2000 and 3000 mile radius ranges (really quite ambitious for the time), resulting the the B-29 and B-32. Of course, by 1939 with Europe in turmoil even these recent ideas were seen as insufficient and the next step up 4000 miles was proposed. Interestingly enough, just the year before the Joint Board (early version of the JCS) determined that the US would probably never need a design for a/c that would exceed the B-17s performance.
                            Finally, in April 1941, USAAC puts out a specification for a bomber that could carry 10,000 lb of bombs to a round-trip mission of 10,000 miles results in XB-35 and XB-36. By this time, FDR has put up the requirements for a massive expansion of the Air Corps and the funding as well so many of the ideas and needs of the Air Corps could actually be put into production.

                            Anyways, sorry for the blathering, my point actually is that while the bomber mafia laid down crucial concepts there were many conflicting issues and technological problems which they had no control of, much less the ability to spend funds on. The idea that more and more defensive armament would be required in the mid-30s for the future didn't really have any reality. In fact, the greater emphasis at that time probably was higher, faster, farther rather than toughing it out to the target. Or that Britain was even a vital link to the European continent which if lost would require extra long range bombers. As for the poor fighter guys, there's no doubt they lost in the battle between the Navy and the Air Corps. Poor Chennault was sent out to pasture until rude awakenings.

                            And I still submit that better powerplants for those planes would have made a bigger difference than adding defensive firepower in the long run. Then again, the same powerplant issue goes for all the early period US fighters. The lack of really good high performance engine development (despite all the Hyper-engine ideas) pre-war hurt the fighter pilots from 1941 to 1943. That's a long time.
                            Last edited by boomer400; 09 Jan 13, 00:29.

                            Comment


                            • #15
                              One note: The postwar B-50 was really just a B-29D. The designation change was done to get Congress to approve money for its development and production as a "new" aircraft design as the politicians were being cheap with money for upgrading existing WW 2 technologies.

                              Comment

                              Latest Topics

                              Collapse

                              Working...
                              X