P-38 Bugged

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

  1. -ALW-

    -ALW- Well-Known Member

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    The P-38 Lightning is now a bit less of a spark with some unusual problem. The plane seems to want to flatspin and stall at much higher speeds. Speeds such as 200mph (350kias).
    Am I crazy or is this a true fact? If so, when one engine fails how will I keep it airborn and travelling in a straight direction when one engine is capable of sustaining only 150mph? Plus, if I do need to use the flaps they don't engage untill at much lower speeds so you guys seem to have forgotten that flaps should be accessible at which speeds where the plane requires it.
     
    Last edited: Jan 26, 2003
  2. daedal

    daedal Well-Known Member

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    Hi,

    P-38, all versions, are OK. You can turn off one of its engines and still fly straight and level at less than 150 mph indicated, make turns and land safely (with or without flaps). And you can reach about 200mph on one engine.

    Tested and confirmed by
    Daedal
     
  3. rgreat

    rgreat FH Developer

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    Ill improve flaps extend speeds...
    Maybe also improve they eefectivenes.
     
  4. -ALW-

    -ALW- Well-Known Member

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    Do you have a film to back that up? I have a certian amount of airspace to recover if an engine is lost, and that usually during combat. Which of course I'll be losing to the new fangled variant. I would compare the performances of the current P38 to the XP-38 which is sad.

     
  5. -ALW-

    -ALW- Well-Known Member

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  6. rgreat

    rgreat FH Developer

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    Damn. :)
    Too many links to read. :)
    Can you quote any data on stall speed and maneurabilty from these sources?
     
  7. Bobby

    Bobby Well-Known Member

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    Last edited: Jan 27, 2003
  8. -ALW-

    -ALW- Well-Known Member

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    Ok, to be fair I would like to see the numbers you used, where you got the information, and how it came to be necessary to change the settings. Was it user complaints? Was there a hot topic in the forum which mentioned info relating to the required changes??

    Give me the list of categories you use. Speed? weight? wing area? engine power?

    The main problems I saw in the P38 before you made it worse, was the top speeds indicated. They didn't seem to add up. Now it's just a bad joke.
    I do wonder if you just made this your own decision to severly handicap another allied aircraft.
     
    Last edited: Feb 3, 2003
  9. rgreat

    rgreat FH Developer

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    I dont feel a need to act as a 'wrong side' in that descussion.

    Feel somthing is modelled wrong? Then convince me that is really wrong. Otherwise do not bother me with such statements as you made with last topic.

    I didnt seen any tech arguments...
    And style of your last message make me feel you dont have any.

    But ok.
    I make one effort to make this discussion productive.
    The combination of weight, wingload, powerload and rollrate give P38 wery bad chances in turnfight against agile opponent.
    Even, american flight tests of 38 vs 190 do not give p38 too much cheers.
     
  10. -ALW-

    -ALW- Well-Known Member

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    What is your source? I think I need an answer.
    Let me explain it this way.
    I need to know what information you use to set the charactoristics of an aircraft. Do you use some opinion from a source? What's the source? The P38 J on out had one of the best rolling charactoristics of any WWII fighter. I'll quote what I have here......


    The P-38J-25-LO production block also introduced power-boosted ailerons. These consisted of ailerons that were operated by a hydraulically-actuated bell-crank and push-pull rod, making it easier for the pilot to maneuver the airplane at high airspeeds. This boosting system was one of the first applications of powered controls to any fighter, and required only 17 percent of the previous stick forces. The hydraulic aileron booster system vastly improved the roll rate and thereby increased the effectiveness of the P-38 in combat. P-38Js with power-boosted ailerons proved to have the highest roll-rates of any fighter.

    Sources:



    Lockheed Aircraft Since 1913, Rene J. Francillon, Naval Institute Press, 1987


    The P-38J-M Lockheed Lightning, Profile Publications, Le Roy Weber Profile Publications, Ltd, 1965.


    War Planes of the Second World War, Fighters, Volume Four, William Green, Doubleday, 1964.


    Famous Fighters of the Second World War, William Green, Doubleday, 1967.


    The American Fighter, Enzo Anguluci and Peter Bowers, Orion Books, 1987.


    Wings of the Weird and Wonderful, Captain Eric Brown, Airlife, 1985.


    United States Military Aircraft since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian Institution Press, 1989.
     
  11. rgreat

    rgreat FH Developer

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    About rollrate.

    [​IMG]

    Roll (without boost) is poor.
    And boost alon do not give you any noticeble improvement before ~280mph.

    This is modelled (as well as increase in roll on P38L on high speeds).
     
    Last edited: Feb 3, 2003
  12. -ALW-

    -ALW- Well-Known Member

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    But does a poor roll rate equate for a tendancy to stall?? That is unecceptable. There are numerous stories I could paste in here that may or may not be factual if that's what you want.
    Where does your info come from?
     
  13. rgreat

    rgreat FH Developer

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    Huh, bad joke imho.

    No 'stories' please unless there is reliable numbers in them.
    Numbers. Graphs.
     
  14. -ALW-

    -ALW- Well-Known Member

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    How can you come to these settings? There is no basis for that information. For one thing....you can't fly those planes so you don't know. You can't put 50lbs of pressure on a joystick and see if that is the output. And I've included the same image with an empasis on the intersecting lines where the roll rates meet. I do find that interesting compared to planes such as F4F and F6F.
     

    Attached Files:

  15. rgreat

    rgreat FH Developer

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    Ask that on american NACA flight testers. Or you think they LIE? ;)

    Now F4F and F6F have a good roll? ;)
    No surprises there.

    For example 190 max rollrate is more then two times faster then the same one from P38.
     
    Last edited: Feb 3, 2003
  16. rgreat

    rgreat FH Developer

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    Ok, im off to sleep now.
    You have time to prepare some worthy arguments before we continue. ;)
     
  17. -ALW-

    -ALW- Well-Known Member

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    Who said you could sleep? :dura:
     
    Last edited: Feb 5, 2003
  18. -ALW-

    -ALW- Well-Known Member

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    Lie? You don't even have a web based link for your info. :nono: OK, I do think that this is getting a bit off the topic I started with. The roll rate isn't something I can or want to negotiate. It was fine, and I didn't ask about it.
    THE problem is what the plane is doing at those speeds at which you fly. If at any particular time, say at 250mph...you decide to loop, or bank, the plane reacts horribly. It will try to spin, torque spin, and stall. That is the main problem. :mad:
     
    Last edited: Feb 5, 2003
  19. -ALW-

    -ALW- Well-Known Member

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    Hey, you hibernating? :zzz:

    Here is something for you to read. I hope you can understand it.

    This is a flight journal of a pilot who ACTUALLY flew this airplane. I think if he was to fly this P38 in WarBirds he would protest to the endth degree.
    Please read below message....
     
    Last edited: Feb 5, 2003
  20. Jochen

    Jochen Well-Known Member

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    Hi rgreat,

    Actually, overall maneuverability (due to roll restrictions) may be less than 'agile opponents'...but we can be more precise. In terms of turn radius, under 3 miles' alt, the P-38 could actually turn inside Fw-190A class ships as well as several variants of the 109Gustav.

    The main factor which was overlooked here, in my opinion, is that the P-38 featured twin, *counter-rotating* engines and propellors. There quite simply was no torque effect, which limited all single-engine fighters. The 38, with its huge wing area, combined nearly 3000hp, and (most importantly), the application of the power through torque-eliminating means, was a MOST impressive low-speed aircraft. Its handling and performance in high-G maneuvers at low and medium speeds was completely out of proportion with its gross weight.

    A bit off topic: if the P-38 utilized two engines and propellors which rotated in the same direction, I am quite sure that it wouldn't have been the low-altitude dogfighter that it actually was.

    Back on topic: the 38's unique engine layout means that stall and maneuverability performances cannot be safely inferred from a simple roll-rate graph. I do not have actual Lockheed numbers (yet,) but in that respect, I'm no different than ANYbody in this debate. :)

    Best regards,
    Jochen
    Kommodore, Jagdgeschwader 27 "Afrika"