1. #1
    When i try to take off i can't hold the plane to a straight line... What's wrong about that??? Is there anything i can do???
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  2. #2
    That's because of the torque. The air is being pushed against your aircraft because of the big propellor you have in front of you. Compensate with rudder to keep it straight.
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  3. #3
    VW-IceFire's Avatar Senior Member
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    <BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by argnan:
    When i try to take off i can't hold the plane to a straight line... What's wrong about that??? Is there anything i can do??? <HR></BLOCKQUOTE>Thats just engine torque. Use the rudder to counter it.
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  4. #4
    Bearcat99's Avatar Senior Member
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    Practice till you get it right.... Set up a DF server offline or go into a QM with no bogies and do touch and gos till you get it right. Like the above posters said.. counter with the rudder.. but practice.
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  5. #5
    Some planes are harder than others, too. The I-153, for example, is particularly tricky. Trying a different plane might help...
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  6. #6
    Tully__'s Avatar Global Moderator
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    Please please please!!!!

    It is NOT torque, it is propwash. Torque causes roll, not yaw.
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  7. #7
    P-Factor is an aerodynamic effect that causes propellor-driven planes to yaw when they are flown at high power and low speed (takeoff and climbout, for example.)

    At low speeds, the plane flies at a substantial angle of attack, and so the airflow is not parallel to the plane's axis. Relative to the plane, the airflow is directed several degrees upwards. Now the prop axis is normally parallel to the plane's axis. As the prop rotates, on one side the blades are travelling upwards and on the other side they are travelling downwards. (On most planes, the prop turns clockwise, as seen from behind, so the left side goes up and the right side goes down.)

    The upwards angle of the airflow causes the downward (right) side of the prop to have a greater airspeed and angle of attack than the upward (left) side. So the downward (right) side of the prop generates more thrust. Pull harder on the right side of the plane than on the left and the plane will yaw to the left.

    This is one of the reasons why most real prop planes need a certain amount of right rudder to keep them straight during takeoff and climbout.

    The other factor that requires right rudder on takeoff (in planes with clockwise props) is spiral propwash. The sideways component of the spiral propwash strikes the vertical stabilizer from the left (in conventional single engine configurations), also causing a yaw to the left. In general, the spiral propwash effect is a lot stronger than P-factor.

    You also need right aileron to keep the plane straight to counteract the rotational torque from the engine(s).

    you also need to consider crosswind
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  8. #8
    RocketDog's Avatar Banned
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    It's also because ground handling is very poorly modelled in IL-2.

    Try taking a B-239 or I-16 up from a grass strip to see what I mean. I very much doubt that in real life an aircraft moving over a smooth grass strip would lurch from side to side the way they do in IL-2. Certainly, when I have seen WWII aircraft flying from the grass strip at Old Warden it all looks very smooth. Nothing like the comedy bouncing and lurching we get, particularly in the roll axis.

    Overall, I think the torque effects are undermodelled (because I have read accounts of Wildcats needing full rudder to get off a carrier and aircraft don't seem to need rudders much in IL-2), but the ground bumpiness is stupidly overmodelled (because real aircraft don't tip from side to side like drunks on grass strips).

    Regards,

    RocketDog.
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  9. #9
    <BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by RocketDog:
    It's also because ground handling is very poorly modelled in IL-2.

    Try taking a B-239 or I-16 up from a grass strip to see what I mean. I very much doubt that in real life an aircraft moving over a smooth grass strip would lurch from side to side the way they do in IL-2. Certainly, when I have seen WWII aircraft flying from the grass strip at Old Warden it all looks very smooth. Nothing like the comedy bouncing and lurching we get, particularly in the roll axis. <HR></BLOCKQUOTE>

    Because these pilots took off of those grass runways numerous times and knew how to compensate.
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  10. #10
    Hm. after some time you'll see that landing is the hardest part (some ac have hard time losing energy like FW190 and is somewhat harder to land than for example Bf109 although Messer have fragile undercarriage you must watch out for that first or second touch down bounce) but..

    other than that; use minimal throttle (30-40%) and brakes to get on main taxi runway line up just nice and begin to accelerate using rudder to correct heading. You will be just fine.
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