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

    Joined:
    Jan 21, 2009
    Messages:
    43
    Likes Received:
    0
    Trophy Points:
    6
    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

    Joined:
    Feb 5, 2009
    Messages:
    356
    Likes Received:
    0
    Trophy Points:
    16
    Occupation:
    Aircraft Mechanic
    Location:
    Florida
    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

    Joined:
    Mar 19, 2008
    Messages:
    636
    Likes Received:
    9
    Trophy Points:
    18
    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

    Joined:
    Jan 18, 2009
    Messages:
    6,418
    Likes Received:
    64
    Trophy Points:
    48
    Location:
    Michigan, USA
    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

    Joined:
    Jun 10, 2004
    Messages:
    7,909
    Likes Received:
    189
    Trophy Points:
    63
    Occupation:
    IT Nerd
    Location:
    Dallas, Tx Jubail, Saudi Arabia
    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

    Joined:
    Mar 19, 2008
    Messages:
    636
    Likes Received:
    9
    Trophy Points:
    18
    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

    Joined:
    Jan 18, 2009
    Messages:
    6,418
    Likes Received:
    64
    Trophy Points:
    48
    Location:
    Michigan, USA
    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

    Joined:
    Apr 3, 2008
    Messages:
    7,995
    Likes Received:
    438
    Trophy Points:
    83
    Nice one, Dave.

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

    Thorlifter Well-Known Member

    Joined:
    Jun 10, 2004
    Messages:
    7,909
    Likes Received:
    189
    Trophy Points:
    63
    Occupation:
    IT Nerd
    Location:
    Dallas, Tx Jubail, Saudi Arabia
    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

    Joined:
    Jan 18, 2009
    Messages:
    6,418
    Likes Received:
    64
    Trophy Points:
    48
    Location:
    Michigan, USA
    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

    Joined:
    Jun 10, 2004
    Messages:
    7,909
    Likes Received:
    189
    Trophy Points:
    63
    Occupation:
    IT Nerd
    Location:
    Dallas, Tx Jubail, Saudi Arabia
    :oops: point taken!!! ha ha ha
     
  12. TheMustangRider

    Joined:
    Dec 22, 2008
    Messages:
    340
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    United States
    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

    Joined:
    Jan 18, 2009
    Messages:
    6,418
    Likes Received:
    64
    Trophy Points:
    48
    Location:
    Michigan, USA
    Germany and Japan were not friends. That might have something to do with it.
     
  14. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,995
    Likes Received:
    438
    Trophy Points:
    83
    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

    Joined:
    Jan 18, 2009
    Messages:
    6,418
    Likes Received:
    64
    Trophy Points:
    48
    Location:
    Michigan, USA
    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.
     
Loading...

Share This Page