P-39Q Airacobra

Discussion in 'Aviation' started by carman1877, Nov 29, 2009.

  1. carman1877

    carman1877 Member

    Joined:
    May 14, 2009
    Messages:
    51
    Likes Received:
    0
    Trophy Points:
    6
    I just was wondering about the P-39Q and what you everybody thought of it? I read that the "Q" model had one 37mm with 34 rounds and 4 .50s two cowling mounted with 200 rounds and 2 wing mounted with 300 rounds. Along with a drop tank or (1) 500 pound bomb under the fuselage. As many people know this plane had the engine in the mid section of the aircraft for several reasons. One is that they wanted to be able to fire the 37mm through the propeller hub, so they needed space in the front. Second they thought that since this was going to be used as a ground attack plane that having the engine in the middle would protect it more from AA fire. And unlike many planes of its time it had doors instead of a moveable canopy. The doors opened forwards like a cars and the window could roll up or down with a crank. People sometimes think that it would be hard to eject from this plane but when you pulled a red lever near the hinges of the door, the door flew off the plane making it easy to get out of. It also had a decent speed and range which is why it was one of Russia's best planes of WW2. The tricycle landing gear was also very knew and inovative for the time. So write whta you think of the P-39Q.

    Thanks
     
  2. Juha

    Juha Well-Known Member

    Joined:
    Jan 8, 2007
    Messages:
    3,734
    Likes Received:
    65
    Trophy Points:
    48
    Location:
    Helsinki
    Hello
    I cannot recall was there 30 or 34 37mm shells. And Russians usually removed the wing guns to lighten the plane and to improve the rate of roll. And against Finland AF's Bf 109G P-39 was more or less as dangerous opponent than Yak-9 but La-5/-5F/-5FN was more dangerous.

    Juha
     
  3. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    A decent fighter, match for the Bf-109Gs and FW-190As in capable hands.
     
  4. FLYBOYJ

    FLYBOYJ "THE GREAT GAZOO"
    Staff Member Moderator

    Joined:
    Apr 9, 2005
    Messages:
    23,204
    Likes Received:
    786
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Aircraft Maintenance Manager/ Flight Instructor
    Location:
    Colorado, USA
    It was Chuck Yeager's favorite WW2 fighter. It could be a bit unstable, it had a lateral and vertical center of gravity.
     
  5. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    I'm not well-versed in that; what is a "lateral and vertical c-o-g"?
     
  6. vikingBerserker

    vikingBerserker Well-Known Member

    Joined:
    Apr 10, 2009
    Messages:
    24,077
    Likes Received:
    655
    Trophy Points:
    113
    Occupation:
    Korporate Kontrolleur
    Location:
    South Carolina
    I always thought it was very under-rated.
     
  7. renrich

    renrich Active Member

    Joined:
    Jan 19, 2007
    Messages:
    4,542
    Likes Received:
    5
    Trophy Points:
    38
    Occupation:
    real estate
    Location:
    Montrose, Colorado
    It had the inherent drawbacks of all P39s, small internal fuel load, it was designed for a pilot who was no more than 5' 8" and there was a large CG shift when the nose guns ammo was used up.
     
  8. Flyboy2

    Flyboy2 Member

    Joined:
    Mar 10, 2008
    Messages:
    676
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Las Vegas, Nevada
    I agree! I've heard it said that the only people who loved the P-39 was Chuck Yeager and the Russians
     
  9. FLYBOYJ

    FLYBOYJ "THE GREAT GAZOO"
    Staff Member Moderator

    Joined:
    Apr 9, 2005
    Messages:
    23,204
    Likes Received:
    786
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Aircraft Maintenance Manager/ Flight Instructor
    Location:
    Colorado, USA
    Center of Gravity - most aircraft have their Center of Gravity (CoG) calculated along stations. The P-39 had a CoG calculation along the water line as well.
     
  10. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    Thanks for the effort to explain, but I'm still within confines of school phisycs that claim that one body has only one CoG.

    What is a "water line" in an aircraft?
     
  11. MikeGazdik

    MikeGazdik Member

    Joined:
    Dec 13, 2008
    Messages:
    531
    Likes Received:
    6
    Trophy Points:
    18
    Location:
    Ohio
    I love the P-39 / P-63. I don't think though, that the engine placement was in part for ground attack. The P-39 was designed as a bomber intercept pursuit. In the same realm as the P-38, all during the AAC fallacy of pursuits only being needed to shoot down enemy bombers attacking the U.S. coast.

    The P-39 ended up being a decent ground attack aircraft after the orginal turbo installation never worked out and the plane ended up with the normal Allison we all know and love. However I cannot recall any wartime pilots talking about the love of the 37mm nose gun either.

    And contrary to what has been repeated in literature, the Russians use of the plane was not primarily tank busting with the cannon. It was a low altitude interceptor. And since the plane performed best at low to medium altitudes, the Russians learned to exploit the true value of the Airacobra.

    Now I have to change my avatar back to a P-39 again.8)
     
  12. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    P-39 was not a decent ground attack plane any more then Spitfire or Me-109.
     
  13. MikeGazdik

    MikeGazdik Member

    Joined:
    Dec 13, 2008
    Messages:
    531
    Likes Received:
    6
    Trophy Points:
    18
    Location:
    Ohio
    I was just trying to make the point that ground attack was not the design genisis, nor was it something into which it evolved.

    I would rate a plane as either; Poor, Decent, Good, or Great, when speaking of ground attack. Poor would be a .30 caliber only fighter, like early Spitfires, and little to no bomb load. The Airacobra at least had a cannon and some .50's, and little to no bomb load. I personally would rank the Airacobra just above the Spit in that regards, so you can choose whatever terminology, but Decent works for me. And if I had my choice, I wouldn't chose to fly and fight in "Decent", I would much prefer Good or Great!

    I really think we agree, just different verbage.
     
  14. FLYBOYJ

    FLYBOYJ "THE GREAT GAZOO"
    Staff Member Moderator

    Joined:
    Apr 9, 2005
    Messages:
    23,204
    Likes Received:
    786
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Aircraft Maintenance Manager/ Flight Instructor
    Location:
    Colorado, USA
    #14 FLYBOYJ, Dec 3, 2009
    Last edited: Dec 3, 2009
    Stations measured from the ground up...

    Although technically correct that a body could have one CoC, you also have to consider where on that object the CoC exists, and in terms of aircraft, where it exists with regards to the Mean Aerodynamic Chord. In the case of the P-39, the designers came up with a fore and aft and "up and down" CoG that considered the large moment (the engine) that was well aft of the datum point (hopefully you know a little about aircraft weight and balance).

    Here's a link that shows a P-39 weight and balance chart. Notice the chart "vertical and horizontal arm and moment."

    http://www.zenoswarbirdvideos.com/Images/P-39/P39WBC.pdf

    BTW, helicopters' CoG are calculated the same way.
     
  15. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    Thanks, FLYBOY, seems I have some reading to do :)
     
  16. tomo pauk

    tomo pauk Creator of Interesting Threads

    Joined:
    Apr 3, 2008
    Messages:
    7,996
    Likes Received:
    440
    Trophy Points:
    83
    Yep, in the scale of 1-4 (4 being the top value), the P-39 could snatch 2.
     
  17. fibus

    fibus Member

    Joined:
    Jun 28, 2009
    Messages:
    52
    Likes Received:
    0
    Trophy Points:
    6
    Winkle Brown and Yeager loved the P39.
    Yeager said no one could beat a P 39 at 100 feet but who wanted to fight there.
     
Loading...

Share This Page