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Proper takeoff procedure...

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Guest Ian_Riddell

>The back row pitched more then the front row? ;-)I once heard an Air New Zealand 767 pilot say that his aircraft flew like a bent banana ... Perhaps the fuselage was bent? :-)If you've ever seen the wrinkles in the top(skin) of an airplane when it's on jacks... you'll realise that a fuselage can bend by a significant amount. In fact, the later 767's have a system which senses fuselage bending with accelerometers and tries to counteract the right to left bending with (automatic) rudder movement. It's an integral part of the yaw damper system.Cheers.Ian.

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If this can be done in your aircraft it must be a unique bird.I tried it in PIC at 200 ft - nope.767 check captain Andre Ludovic who maintains his smartcockpits web site shows the earliest you can engage AP in roll mode is 400 ft and in LNAV or HDG SEL modes. Nothing about TO-TO.The guy who implemented simulated 757 for FLY told me that his "NASA survey" of autopilots (whatever it is) and his 757 manuals indicate TO-TO is FD only.The PIC documentation is not 100% clear but says TO-TO means "FD is in takeoff mode". No other roll or pitch mode has this 'FD' qualifier.Michael J.

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Guest

Those you provide are really detailed, thanks~

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Is it normal to reach V2+15 during rotation?? I always have to pitch the airplane with a high bank angle to reduce speed. What bothers me is why I reach V2+15 so quickly.... maybe a slow rotation problem? If I do it faster I can tail strike my plane. If I do it slower the plane accelates too much.

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Guest Martin

Gain speed quickly is exactly what you want to do during takeoff. But if it is excessive, make sure you are having a good flap setting and de-rate for your weight. If you are light, a de-rate - or to be specific, an assumed temperature - of 50C or more will do the job. If you still reach V2+15 quickly, and you accelerate further - don't bother, it's not a problem, it's a good thing. Accelerate at a higher speed if desired. What you need is obstacle clearance and speed, in case of an engine failure, and that is what you're getting.Martin767 fetishistIt's a lot like life and that's what's appealing

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Guest Ian_Riddell

>If this can be done in your aircraft it must be a unique >bird.Not quite unique, Michael.... ;-)This is the response I got from a UPS pilot..."It depends on the model of Flight Control Computer.On all of our 767s (767-300ER) and a little more than half of our 757s the A/P will engage in the TO mode. In our remaining 757s, which have a different model FCC, if the A/P is engaged while the F/D is in the TO mode, the A/P engages in its default modes of V/S for pitch and HDG HOLD for roll."It would be interesting to see the full results of that survey you mentioned (especially with regard to 767-300's).Cheers.Ian.

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Guest Ian_Riddell

> Gain speed quickly is exactly what you want to do during takeoff.Yes and no.... Boeing consider V/S to be of primary importance just after liftoff. The FD commands are programmed this way. If the airplane has achieved a certain minimum required V/S, say 600fpm, it will then mix V/S speed with airspeed. With V/S, say double the value, it concentrates on airspeed alone... and will try to hold the airspeed below a maximum of, from memory, V2+25. However, the ideal speed is V2+15 on a 767.As mentioned in a previous message, the V/S component is to ensure that windshear/downdrafts after liftoff do not slam the aircraft back down on the runway.Obstacle clearance is achieved with a combination of both V/S and airspeed (Higher airspeed allows you to retract your flaps quicker, which means that you have less drag, which means you can accelerate quicker... to even higher airspeeds. Higher airspeeds allow you to climb more quickly). If the obstacle is close to the end of the runway, then V/S is important. If the obstacle is more distant, then airspeed becomes important. On aircraft like the 747-400, it may determine what flaps settings are used for takeoff (It may be the same for 767s also(?)).Rotation is an art (practise makes perfect ;-)).Cheers.Ian.

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Guest fwsov

There isn't anything wrong high V/S due to a high airspeed but if the plane accelerates in an insane manner and requires a 30degree pitch up to keep the speed below V2+25 then maybe you would be better off with a de-rate. I'm basing this on the assumption that those engines are going at a flat out T/O speed, conseqently increasing the risk of an engine failure enourmously and I'm not certain on this but a catastrophic engine failure at 32degrees of pitch would be a VERY uncool thing to have and would result in a violent yaw that would need correction as well as quite a big pitch down.------------------------------------------Skipper-$500,000 dollarsAll australian crew- $4million dollarsWinged Keel-$400,000The look on Liberty's face after the 1983 Amererica's cup?-Priceless...

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They say a recommended pitch rotation rate is 2 deg/sec.I often takeoff at about 300,000 lbs and with this weight you will be going all the way to about 18 deg pitch. I may even go faster than v2+20 with this pitch but so bid - I definitely do not go over 19 deg with the pitch.Michael J.

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Guest HPSOV

Our recommended rotation rate was 3 degrees a second, but after a few too many tail strikes it has been reduced to 2.5 degrees a second, or 2 after an engine failure.Basically at light weights your speed will get to V2+25, but this isn't a problem, it just requires a positive rotation all the way up to say 20 degrees if required.Its a powerful aircraft when both engines are running, enjoy it!

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Ok.. Now, regarding tail strikes.I Changed the contact point crash sensitivity to simulate tailstrikes, I wanted the plane tail to break apart in case of tail strike so I will avoid high pitch angles at all costs.I Did the following:I Changed the variable that corresponds to 'damage' for the contact point Number 5 it was 787.402 I changed to 187.402 Also changed the sound type to 9 and replaced the wav's for tail strikes with some wav's I found with screaming passengers. SO If, for some reason I tail strike my plane I will hear pax screaming and my plane will crash (I can manage to land it with some luck) but it is almost uncontrollable.Why I'm telling you this? because I found that I was tailstriking at a 7 degree pitch angle and that sounds unrealistic.. I tought it was 9.5 so I changed the contact point a little bit up to allow for some more space.The Question:What is the exact Pitch angle that will make a 767-300 tail strike on rotation? Maybe most of you haven't noticed.. but I can bet a lot of people here tail strike on rotation without even knowing. Taking off with PIC and every aircraft in Flight Simulator was a no brainer for me... now, knowing that if I tail strike I can crash I take rotation very seriosly... It is, indeed, an art.Thanks,

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Guest Martin

Right. Of course you have to get the balance right, but if you have a light plane and lots of speed (and it's understood that you also have a good climb rate), there is no need to complain about the high speed, unless there's a mountain right in front of course.Martin767 fetishistIt's a lot like life and that's what's appealing

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Guest HPSOV

The exact figure, is 9.8 degrees nose up. This assumes landing gear struts fully extended.However.... to complicate things, very few tailstrikes occur when the aircraft is still on the runway. Most occur about 2-3 seconds after lift-off, during a strong crosswind, when then tendancy is to "######" the aircraft off the runway, as it is being pushed sideways by the wind. If you're not careful you can easily get an attitude of nearly 15 degrees, while still only 1-2ft off the runway, which is enough to cause a tailstrike.

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Guest

Yes...DC9's were hinged :)but seriously, I've flown up front and way in the back and when you can look up the aisle, you get a stronger "sense" of pitch.michael

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