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Guest bob

Rotate!

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Hi Seasonal greetings and a pleasing 2004 to all.I really enjoy my PMDG 737'sHowever, the only niggle I have is having set everything up for the take off run, when at rotate speed indicated plus oral notification, I rotate my CH yoke but I cannot rotate until around 40 knots faster!is this normal within the FS contraints or am I doing something wrong. I have setup pitch trim.I would be grateful for any suggestions to overcome my problem.Many thanksBob Wright

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Same thing happens to me....V1, Rotate and then when i pull back on the stick, the plane only starts lifting about 4 seconds later..... Dunno why though ?

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Also check your joystick or yoke calibration. I had a similar problem with aileron trim.Jeff

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Another thing: Don`t fly on the numbers all the time...if you got enough runway...use it! Nothing wrong increasing the safe margins.

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I would suggest making sure your trim is set, and that your flaps are set properly.

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HiThanks for your interest, judging from the remarks, can I assume that most of you are taking off at rotate speed? I just feel the prolonged and late rotate leads to a much higher speed during climb out, thus, not realistic.Bob

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Hi BobWhen 'Rotate' is called I have to pull the yoke all the way back and then wait a second or two but it does climb eventually. Doubtless more trim would solve this apparent problem but then, once off the ground, there would be a tendency to climb too steeply. As it is, it climbs at V2+25 almost hands off once airborne. I've always assumed this is the way it is meant to be. Much better than leaping off the tarmac at the slightest nudge I think:-)Paul Croft10 miles SE of EGLL

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I don't have any problem rotating at the targe speed. I a smooth pull when the call is made, rotate at about 3 degrees per second and arrive at target attitude at v2+20 IAS.A couple of thoughts...1) I know I said it earlier, but I had to recal. my joystick after the installation of SU2 via FSUIPC. For some reason, things were a little off.2) With the throttle open while trimming, I have noticed that the bug moves "back" (towards 0) briefly when you release the trim buttom. You made need to add an additional burst of trim to make it to the correct setting.A few questions... what trim settings are you using and what version of FS are you using? What is your takeoff weight? What are your compute V-speeds?thanks!Jeff

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"Rotate" is not the same as "lift off". You should get to the takeoff attitude in a few seconds (the three degrees per second is about right) and should lift off shortly after reaching the target attitude.So four seconds after you pull up is about right.V2 is not the lift off speed either - it's the speed at which you can safely climb away with an engine failure. You normally are climbing at V2+15 or faster.

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Good points Tim. I usually blast through V2 before the nose wheel gets off the ground. Trim is critical in the sim and I'm usually over +6 units for t/o, anything less it seems she will "stick" and it makes for a sharp jerk up when the airplane does get airborne.I fly as a pax on the Aloha 737-700 (with winglets) birds between Hawaii and the mainland on a regular basis. We use up a good chunk of the reef runway at PHNL (but not as much as a 747 or DC-10, of course) and are probably close to max TOW if the cabin is full. I can feel a bit of hesitation on rotation as the entire weight of the airplane gets shifted from the tires to the wings, they seem to rotate a bit slower than the 3 deg per second that is typical, not sure if that is due to concerns of a tail strike or just building a little more airspeed margin before the pitch goes all the way up...interesting thread, anyway.regards,

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"Wow, what the heck kind of advice is that?"LOL... I suppose if the tyres are rated at 300kts, there isn't a large obstacle just beyond the end of the runway, and a check captain isn't sitting next to you, it's ok? (or have I missed something more obvious?).Cheers.Ian.

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Chris, the amount of runway you use up is directly proportional to the amount of thrust reduction used on takeoff. Typically, thrust is reduced as much as possible to provide less wear and tear on the engines and provide maintenance discounts by CFM.Upon rotation, the entire weight is not shifted from the tires to the wings, I think about 20% of the weight is still present on the wings right before rotation. This is why ground spoilers exist: At high speeds there's so little weight on the wheels that wheel braking is very ineffective.There is always a risk of tail strike, even with the -700, where it occurs at I believe around 11 degrees pitch up, and this is usually the reason why some pilots do a two-step rotation technique and wait for the 'click' (the sound of the gear lever latch releasing, indicating that the air/ground sensing system is in 'air' mode) before continuing rotation to the climbout attitude. Nothing wrong with that, since the margins are very slim.The tail clearance on a standard rotation (continuous rotation) takeoff for a -700 is only 29 inches (73cm) between the tail and the asphalt (-800: 20 inches/51 cm).Normal trim setting on a -700 or -800 is usually between 4.5 and 6 units.Iz

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on should take to the skies once he has the speed to do so, so once past V2 one should be going up at all times(liefst eh...)figures exist for a reason...Well that's what i've been taught anyway

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