P-38 Bugged

Discussion in 'Engineering Retrospective' started by -ALW-, Jan 25, 2003.

  1. Vadim Maksimenko

    Vadim Maksimenko Well-Known Member

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    А теперь сам прочти, что написал... вычти из указаного веса две тонны... бред не напоминает? ;) Двух-моторная, двух-балочная гаргара, с крылом большего удлинения легче в полтора раза меньших самолетов??? :D :D :D
     
  2. Vadim Maksimenko

    Vadim Maksimenko Well-Known Member

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    Все звучит красиво, пока мы не вспомним о лобовом сопротивлении, которое напрямую зависит от поперечного сечения профиля. И чем больше удлинение, тем это лобовое сопротивление больше ;) И больше оно ровно на столько, на сколько больше удлинение :D Сюда еще стоит добавить, что крыло большего удлинения будет и толще, поскольку трудно делать прочное длинное крыло.
     
  3. Vadim Maksimenko

    Vadim Maksimenko Well-Known Member

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    Это ничто. Роль играет только удельная мощность. Ты бы еще Б-17 в качестве примера привел.
     
  4. Bobby

    Bobby Well-Known Member

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    Только параметры для оптимизации выбирают различные. Курт Танк пошел ради повышения ролла на такие жертвы по размаху крыла, что фокер при остановке двигателя предписывалось покидать с парашютом, а Лайтнинг разрабатывался с учетом дальности полета, которая 190 даже не снится.
    Очепятка - 30,5 м^2

    По поводу мощности двигателей то же передергиваешь, для 190 указываешь форсированый режим 2100HP, а для Лайтнинга номинальный. :nono:
     
    Last edited: Mar 17, 2003
  5. Vadim Maksimenko

    Vadim Maksimenko Well-Known Member

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    Просто максимальные значения. Я понимаю, что если 190 попытается маневрировать с Лайтнингом на 7-8 км, то ему ничего не светит :) Но на высоте наших обычных сражений П-38 может только удрать.
     
  6. Vadim Maksimenko

    Vadim Maksimenko Well-Known Member

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    Дальность полета определяется емкостью баков в первую очередь. К тому же мы знаем, что с нагрузкой на крыло у 190 было изрядно лучше. Да и с двигателем тоже: BMW-801D-2 имел непосредственный впрыск и был экономичнее. Так что не в кассу.

    А покидать самолет было предписано по одной причине: пилот дороже самолета для немцев был. Им нафиг сдалась лотерея на вынужденной. Это не как в некоторых странах тех времен, где люди были дешевле грязи.

    Это не ко мне, а к ALW, пожалуйста. Это он площадь крыла в 220 кв.футов указал. Я лишь перевод в метры сделал ;)

    Шутник ты, однако :D 1475 л.с -- это какая мощность?
     
  7. -ALW-

    -ALW- Well-Known Member

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    So then, we are speaking of aerodynamics relative to diving. If the shape of the aircraft is such that it may restrict and cause some drag, that will not be the case unless there is a greater pull from say, an engine. The discussion of speeds acheived during level flight at certain altitudes is more interesting.
     
  8. -ALW-

    -ALW- Well-Known Member

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    Wing loading is important for anything airborne I think.
     
  9. -ALW-

    -ALW- Well-Known Member

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    I was going to mention that at some point, but I wondered if the discussion was being applied in some way to the matter of the P-38's performance. -exec- seemed to just pass gas :ass: in my direction when I asked other people, not HIM what was being discussed as it made no sense to me at all and in no relation to the topic.
     
  10. Sea

    Sea Well-Known Member

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    In this theme from discussion P38 smoothly went to discussion of planes and aerodynamics. I have offered to leave in this theme discussion only P38, and for other discussion to create another thread. As translate all Russian text can be very hardly. I use the computer translator and not always it is possible to understand exact sense translated :) :rtfm:
     
  11. -ALW-

    -ALW- Well-Known Member

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    Yes, that is a good point to make, but I must stress the the shape and charactoristics do suggest it is not like a B-25 flying through the air.
    One must take note that the P-38 has a very low profile and sleek shape comparable to most any aircraft. The P-38 was the ONLY aircraft in the world at the time in action that had flush rivoted skin which GREATLY reduced drag and increased speed. The canopy for example was built much more aerodynamically clean than the 109's squarish and flat canopies. Just look at the images I posted and you have to admit it is very aerodynamically sound. The super clean and smooth shape is what led to compression problems.

    If you take each boom and compare it to a 109 for example, you can just basically set two aircraft side by side and get an idea of what you get in a P-38. To assume that because the P-38 is larger makes no basis in my opinion to expect the aircraft to perform worse. I rather think that the P-38 has a good power to weight ratio when compared. Just because the P-38's engines each produce less horsepower than what a 109 or 190...or even a P-51 does, that won't matter. I think if you were to split the weight of the P-38 in half and consider each engine alone providing for each half of the weight, drag, and lift it would be possibly comparable. This does not included the shape of the wing on the P-38 which creates much lift.
     
  12. -ALW-

    -ALW- Well-Known Member

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    I think you better rethink your data. You err miserably with that view.

    [​IMG]
     

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  13. -ALW-

    -ALW- Well-Known Member

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    Here is the front cover of my book...guess I can let you guys see this :dura:

    [​IMG]
     

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  14. -ALW-

    -ALW- Well-Known Member

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    Does the shape of the wing not matter? Wing area seems like it is discussed like it is a flat peice of metal. The shape of the wing should make a difference to me.
     
  15. -ALW-

    -ALW- Well-Known Member

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    On the point bobby makes, I believe he is correct. The shape of the wings are maybe not modelled for each aircraft individually, but rather the same for all (fighters) which leads to a problem I would think! The thickness of the wing of a 109/190 are MUCH different for example than the P-38.
    Like I've asked rgreat before, I would like to see what the specs are for the aircraft in WB if that's possible. They MUST have SOME kind of information; otherwise, what do they use?
     
  16. -ALW-

    -ALW- Well-Known Member

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    I would think you don't turnfight untill at much lower altitudes. But in any case, I would say it was below 5,000 ft.
     
  17. -ALW-

    -ALW- Well-Known Member

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    Do you really expect that information to base any credible data?
    I think you miss the point.
    Post reading error. You have no idea what the situation was. Do you think only P-38 pilots made errors?
    How did Hans-Joachim Marseille die?
     
  18. -ALW-

    -ALW- Well-Known Member

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    I think that is a moot point in this case Vadim.
    Can you depict the aspect ratio to prove that point?
    Can you show a comparison between this aircraft and another one?
    Read this post carefully: Keep in mind that wing produces a good amount of lift.

    [​IMG]
     

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  19. -ALW-

    -ALW- Well-Known Member

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    I really must say...that doesn't look like a big fat wind plow.
     
  20. -ALW-

    -ALW- Well-Known Member

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    "Flee" is not in my vocabulary :turret:
    But then of course, it is now with the 1.50/1.51 variant. :rolleyes: