Performance difference between the A6M5a and A6M5b/c

Discussion in 'Flight Test Data' started by shiro_amada_jp, Mar 16, 2009.

  1. shiro_amada_jp

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    Aside from having an additional armament and ammunition, how did the A6M5b/c model differ from the A6M5a model of the Zero fighter? Did the additional load of the A6M5b/c model hamper its turning ability?
     
  2. Sweb

    Sweb Member

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    Everything I read about the two indicate the latter was a poor performer by contrast to previous models. It was an out-moded design that needed to be replaced rather than reworked. But, that's true of any airplane pushed beyond its design limits. One thing I've mentioned here is the Japanese did not have the ability to refine 100 octane aviation fuels so they never did realize the full potential horsepower available in any of their engines. 80 octane was the best they could produce in sufficient quantity to meet demand. The US used only 100 octane fuels and if that wasn't available in an emergency 80 octane could be substituted. But, performance fell off quickly with the 80 octane so it was used primarily for non-combat aircraft using similar but derated engines and only for ferrying combat aircraft to save the 100 octane for the combat role. The A6M-series, and all other Japanese types, would probably have been much better performers on 100 octane fuel.
     
  3. Ivan1GFP

    Ivan1GFP Member

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    Hi Sweb, shiro_amada_jp,

    The standard for Japanese aircraft fuel during the war was 92 octane not 80. This is mentioned in all the TAIC tests I have seen.

    The A6M5 Model 52a is my favourite of the Zeros. It finally had a passable ammunition load for the long barrel version of the cannon (not great but passable). Earlier guns only had 60 rounds which in my opinion is totally inadequate. After the 52a, the Zero only got heavier with no additional power until the A6M8. There were also some strength improvements in the A6M5 series which allowed higher diving speeds (460 mph which still wasn't very good but quite a bit closer to its opposition).

    - Ivan.
     
  4. davebender

    davebender Well-Known Member

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    That is undoubtedly true. However wartime production needs forced everyone to keep out moded aircraft in production. The Zero was no more obsolecent then the P-40, F4F, Hurricane, Swordfish and Ju-87.
     
  5. Thorlifter

    Thorlifter Well-Known Member

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    That's a good point Dave

    Yes, the P-40, F4F, and Hurricane were at their design limits at the wars end, but they were still relevant, and successful, in their roles.

    I, again, agree with you that the Zero was at its design limits, however, it would have been interesting to know what it could have done with the proper fuel.

    Still, a flying fuel tank is a flying fuel tank.
     
  6. Ivan1GFP

    Ivan1GFP Member

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    Perhaps the Zero was an outmoded design. I believe that the real issue was that all the other fighters you mentioned had a serious increase in engine power to keep them current. The Zero really did not. If you look at the power curves of the A6M2 versus the A6M5 with power plotted against altitude, the lack of increase may surprise you. The speed and climb rates of the late Zeros were very close to those of the early versions. What it really needed was what it got with the A6M8 with a Kinsei engine. Pity that combination never saw action.

    Another issue was the one I mentioned in passing: The airframe was very weak. It had serious limitations as far as aerodynamic loads which is why the diving speed could not be increased all that much. It met an impossible set of performance requirements by sacrificing excess strength and growth potential. Jiro Horikoshi's book "Eagles of Mitsubishi" is a pretty good read to figure out the choices that were made for this plane.

    - Ivan.
     
  7. davebender

    davebender Well-Known Member

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    Japan did not fight many CV air battles after 1942. So pouring development money into the A6M CV fighter aircraft would have been a waste of money.

    Instead they should have fixed the Ki-61 aircraft program. That would give them a competative aircraft for operation from all those island air bases. Better yet, they should have mass produced the dirt cheap Me-109F4 under license with no design changes to either the engine or airframe.
     
  8. tomo pauk

    tomo pauk Creator of Interesting Threads

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    Nice one, Dave.

    Now, we did have many 'what ifs' for other countries, but none for the Japs...
     
  9. Thorlifter

    Thorlifter Well-Known Member

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    Well that makes for an interesting thought. What if the Japanese used the Bf-109 in the Phillipines and armed New Guinea and Rabaul with them. Sure, the 109 hard horrible range compared to the Zero so it would have to stay close to the islands or base.

    How much would it have mattered? How much would tactics play into it?
     
  10. davebender

    davebender Well-Known Member

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    Everything except the P-51 had horrible range compared to the Zero. Hence the A6M should be reserved for use as long range bomber escorts.

    Me-109F combat radius is not that short. Aerodynamic improvements that made it faster also made it more fuel efficient. Add a pair of drop tanks and combat radius is comparable to many other WWII era fighter aircraft like the American P-40.
     
  11. Thorlifter

    Thorlifter Well-Known Member

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    :oops: point taken!!! ha ha ha
     
  12. TheMustangRider

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    Maybe it would had been a good idea for the Japanese to mass produce the BF-109 under licence, but perhaps they would had been somehow reluctant to do it because of their pride (I'm saying this out of a pure speculation) since it would had meant for them that they were turning on German aircraft because they were unable to produce competitive fighters against newer American machines.
     
  13. davebender

    davebender Well-Known Member

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    Germany and Japan were not friends. That might have something to do with it.
     
  14. tomo pauk

    tomo pauk Creator of Interesting Threads

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    National pride aside, I'd really like to see the 109F airframe with Nakajima Ha-109 (from Ki-44) or Mitsubishi Kasei aboard ...
     
  15. davebender

    davebender Well-Known Member

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    If the Me-109 and DB601 engine had been available a couple years earlier it might have been produced under license in China. Most of their military equipment was German designed. That would put a serious dent in Japanese air superiority.
     
  16. taly01

    taly01 New Member

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    Sorry for resurrecting old post but i thoughtfully wrote below before I realised 2009!

    Not getting the 1350-1500hp Kinsei motor into the Zero until 1945 was the big error.....BECAUSE........the A7M program was a huge time waster and ultimate failure.

    The A6M5 was just OK for 1943, I think the A6M5c was really a fighter-bomber design as it came with rocket rails, bomb racks and extra wing guns none of which would help fighter performance.
     
  17. Thorlifter

    Thorlifter Well-Known Member

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    No issues with resurrecting old posts.

    109 vs A6M. Hmmmm, 1940-1941 All things being equal I'm thinking same general outcome as A6M vs P40 or A6M vs Hurricane. Low and slow the A6M will dominate. At altitude and boom and zoom the A6M is in trouble. Your thoughts?
     
  18. CORSNING

    CORSNING Active Member

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  19. taly01

    taly01 New Member

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    Up to 1942 the A6M2 was a great plane no doubt, at that time maybe only the Me109F was fast enough to overcome its better turn ability.
    But I don't think the Japanese would ever have adopted the Me109 though cause they were obsessed with turn fighters. I remember reading about a frontline unit testing a Ki-44 and they thought it was no good because it couldn't keep a maneouvering Ki-43 in its gunsight!
     
  20. GregP

    GregP Well-Known Member

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    #20 GregP, Aug 11, 2017
    Last edited: Aug 11, 2017
    I'm not all that sure the Zero was at it's design limits.

    The ailerons were delightful until high speed. They could have been changed to ailerons and elevators better-suited to higher speeds and the control system mechanical advantage could also have been reworked. Just because the Sakae 31 was near it's limit does NOT mean another engine that made more power could not have been made to work. The Ha-112-II Kasei was lighter than the Sakae 31, made 1,500 HP, was relaible, and it worked quite well in the Ki-100 that originally has a much smaller overall diameter engine in it.

    All of the above said, I think the Zero WAS at or near it's limit with the existing engine and design. Everything above is meant to suggest design changes to the airframe that enhance either power or higher speeds.

    A lot of folks thought the P-40 was a dog. Then the XP-40Q came along and showed what could be done with design changes. That we didn't buy it is our own fault as it would have represented a major step forward everywhere the P-40 was in actual service. Wherever it went (replacing a P-40) the XP-40Q would have been a quantum leap in performance. And we used a LOT of P-40s, right to the end of the war. I completely disagree with the guys who said it wasn't needed and didn't fulfill any role. It could have replaced older P-40s that were still serving and was a MUCH better airplane than ANY of the standard P-40s. It STILL had the same range of a standard P-40, and would give a P-51 hell all day long. That's an improvement over an existing P-40, no matter how you slice it ... and we were were USING P-40s on the last day of the war.

    The Fw 190 was a very good aircraft. The Ta 152, developed from the Fw 190 was quite a bit better, even if too late to be of much use.

    The Spitfire got a major face lift with the change to the Griffon engine.

    The P-51 started out as a good plane and got a major face lift with the change to the 2-stage Merlin.

    There is nothing saying the Zero could not have been reworked in the same manner, especially with the Ha-112 II Kasei engine. That they didn't DO it is probably more a testament to the effects of continual attacks rather than inability to rework the A6M design. Would it have taken effort? Yes. But much LESS effort than was expended on things like the Kyushu J7W1 Shinden that made only one or two wartime flights, and none in combat. There are numerous others that come to mind as useless wastes of effort that might have been better put to use with a reworked Zero airframe.
     
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