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P40 and P39

Discussion in 'Aircraft' started by GunSlinger86, Apr 5, 2016.

  1. Sheldrake

    Sheldrake Member

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    The manufacturers advertisements for the P39 included illustrations of it as a tank buster. They were published or may have informed illustrations of the P39 in the Daily Telegraph supplement The War Illustrated. That may have been some marketing positioning after the P39 turned out to be a dog at altitude.

    Here is what appeared in a 1943 article in Aviation quoting Larry Bell talkinmg aboutn the fundamentals for the P39 design
    http://migrate.legendsintheirowntime.com/LiTOT/P39/P39_draft.pdf

    One way to read that was for a design aim for ordinary fighter characteristics such as speed, maneuverability, and pilot protection; but exceptional firepower, pilot visibility and good landing and ground characteristics. Three out of five targets listed form the firepower were on the ground or water.

    Bell's innovation of the engine behind the pilot was controversial and not followed by anyone else. He had designed an unforgiving aircraft with a reputation for unpleasant handling. This is supported by the accident rates in the Army Air Corps statistical digest Table 214 airplane accidents in the Continental US. The P39 suffered 245 accidents for every 100,000 flying hours, 50% more than the P40 and twice as many as the P47 and two and a half times as likely than the P51 (100 fatal accidents per 100k hours). Worse still 47% of accidents were fatal for the pilot, compared to around 17% for the P40, P47 or P51.

    The P39 had drawn the short straw. Maybe five times more likely to die in a flying accident than a P51 pilot, even before facing an enemy in combat. 369 P39 Pilots died in flying accidents in the USA - enough for eighteen fighter squadrons - six fighter groups.
     
  2. RichTO90

    RichTO90 Well-Known Member

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    The P-38 was designed under a 1936 USAAC specification for a twin-engine, high-altitude, interceptor.
    The P-39 was designed under a 1936 USAAC specification for a single-engine pursuit (fighter).
    The P-40 was not competed, since it began as a request from Curtis to the USAAC for the mounting of an in-line Allison V-1710 in the 10th P-36A as the XP-40. It built on a USAAC request to Curtis for the XP-37, which was the V-1710 on the P-36. The P-36 was also built to a pursuit specification from 1935. So technically, the P-40 design was older than the P-38 and P-39.
     
  3. GunSlinger86

    GunSlinger86 Well-Known Member

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    So interceptors go after bombers and aren't as agile, pursuit are supposed to be fast, agile dog-fighters?
     
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  4. CAC

    CAC Ace of Spades

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    Interceptors lose at little agility for climbing speed and weapons...there's a bomber or fighter/buzz bomb, go get it...fighters usually have have all the other roles...
     
  5. Takao

    Takao Ace

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    Yes, At the time...Interceptors tended to be faster, but less maneuverable, and pursuits tended to be not as fast, but more maneuverable. However, as high-horsepower engines became more mainstream, this line was quickly blurred.
     
  6. the_diego

    the_diego Active Member

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    could there have been a later faster version? accounts on both sides almost always say the p-40 can out-dive a zero and little else. diving, by the way is the one weakness of the zero in the first year of the pacific war.
     
  7. Takao

    Takao Ace

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    Of which, the P-40 or the A6M Zero? Because faster versions of both were built later in the war.
     
  8. TiredOldSoldier

    TiredOldSoldier Ace

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    AFAIK both the P40 and P39 were not globally as good as to the contemporary axis best front line fighters (A6M and Me 109). Against bombers or the underarmed JAAF and Italian fighters it could be a different story and early in the war there were plenty of those around.

    Even against first line opposition they could do their job with appropriate tactics that maximized they relative strengths, what I always wondered about the "diving attack" tactic is that it should require having a height advantage so climbing speed as well as diving speed is important, unless you start the fight from with a height advanage, and climbing speed of was not the P40's forte.

    The "soviet view" is often quoted as a defense of the P39 but do we have any Luftwaffe reports about to confirm it ?

    The A6M had very low wing loading and could never be "fast" compared to similarly powered fighters, it also was a rather extreme design regarding weight savings, great concept for a carrier fighter but not so good if you get into an attrition campaign like the Guadalcanal one was.
     
  9. Sheldrake

    Sheldrake Member

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    No one knew how, or even whether, air to fighting would take place with the streamlined all metal aircraft of the late 1930s. There were different ideas about what an interceptor aircraft looked like and how it might be different from a pursuit/fighter. No one knew how much firepower was needed to shoot down all metal bombers. The RAF had opted for 8 x 303 because it would demolish the contemporary canvas and wire aircraft but dabbled with 20mm cannon in case they got that wrong.

    Designs optimised for firepower included the Me110, Bristol Beaufighter and Westland Whirlwind. The Boulton and Paul Defiant used a turret and a parallel attack path to eliminate the problems of deflection shooting.

    There was a trade off between the armament and agility, oddball designs were discontinued with the leading single seat aircraft used for a range of purposes - interceptor, escort, air superiority, ground attack, dive bombing etc. However, units variants might be optimised for one role over others. E.g. the Fw190 Sturmbock
     
  10. GunSlinger86

    GunSlinger86 Well-Known Member

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    The P-39 with the good high altitude supercharger system could have been a great plane, and the P-63 with the better engines showed the same thing, that they could have been solid performers. Later modified versions performed up to par with the competition.
     

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