Takeoff with light quartering tailwind
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From: 41S174E
Hey Jammedstab, I have never flown the -200, but the 3 4 and 800's have 'aileron trim units' on the yoke. Are you sure you are not getting mixed up with these markings?
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From: GPS L INVALID
Seems I was correct about 1.6 units - thats when the flight spoilers start to show a deflection, just tried it out today (well, between 1.5 and 2, its a very small difference anyway)...
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From: In a far better place
In all the Boeings from the 727 up to the Whale, the takeoff run is started with the wheel neutral. As you know a plane is nothing but a big weather vane. If the wind hits the right side of the vertical stabilizer the nose will want to go the right. Thus you need left rudder to offset the effects of the crosswind. The amount of left rudder input will decrease as the speed increase and the airflow over the vertical stabilizer takes effect. At the point of rotation, not being a Microsoft or simulator pilot, attention is outside the cockpit and not at the control wheel.
That said if I maintain left rudder input with the wheel neutral at rotation the aircraft will veer left and eventually roll left too. Thus you need to input right aileron. How much? Like I said, not being a simulator or Microsoft pilot I use sufficient aileron to maintain a wings level constant heading at the point of lift off. After liftoff then the aircraft is deslipped by neutralizing the controls and finding the proper crab angle to maintain desired track. Nothing scientific about a crosswind takeoff. Works the same way in Cubs, Stearmans, Pitts, Extras, Cessnas, Beechcraft, Commanders. I will say the only aircraft which is a bit twitchy on crosswind takeoffs was the good old reliable Aircoupe... no rudder pedals
!.
That said if I maintain left rudder input with the wheel neutral at rotation the aircraft will veer left and eventually roll left too. Thus you need to input right aileron. How much? Like I said, not being a simulator or Microsoft pilot I use sufficient aileron to maintain a wings level constant heading at the point of lift off. After liftoff then the aircraft is deslipped by neutralizing the controls and finding the proper crab angle to maintain desired track. Nothing scientific about a crosswind takeoff. Works the same way in Cubs, Stearmans, Pitts, Extras, Cessnas, Beechcraft, Commanders. I will say the only aircraft which is a bit twitchy on crosswind takeoffs was the good old reliable Aircoupe... no rudder pedals
!.
Last edited by captjns; 18th January 2012 at 03:00.
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From: nowhere
Photos: Boeing 737-201 Aircraft Pictures | !!!!!!!!!!!!!!
It is a bit difficult to see but if you look closely at the top of the control columns, you will see that it says "Control Wheel Degrees" and the markings go from 0 in the middle to 50 on either side.
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From: nowhere
Actually 737-200 FCTM dated April 30 2005 on page 3.11 says..." Maintain wings level during the takeoff roll by applying control wheel displacement into wind"
Not sure where you got your info from.
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From: nowhere
I disagree. On the 727, I used to initiate the takeoff roll with aileron into any significant(my estimation) wind and maintained aileron into wind throughout the roll(although it would back off somewhat as speed increased). Aileron was maintained into wind throughout the rotation as I didn't want a wing to drop during the rotation when they are closer to the ground. Worked well.
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From: In a far better place
You are entitled to your opinion JammedStab
After some 20000 of PIC jet time with 5000 plus hours of Captaining the finest jet off the Boeing assembly line, the good old reliable 727 that is, I never had a near excursion or overrun on takeoff using my technique. The FAA was satisfied as well as I trained some of their folks too. At the end of the day, I guess what ever works...
My point is that one's attention during the takeoff roll should be out the window and not at the control column and provide the appropriate control input accomplish a successful wings level takeoff.
After some 20000 of PIC jet time with 5000 plus hours of Captaining the finest jet off the Boeing assembly line, the good old reliable 727 that is, I never had a near excursion or overrun on takeoff using my technique. The FAA was satisfied as well as I trained some of their folks too. At the end of the day, I guess what ever works...
My point is that one's attention during the takeoff roll should be out the window and not at the control column and provide the appropriate control input accomplish a successful wings level takeoff.
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From: US
Crosswind takeoffs - at liftoff the cross control should be approximately the same as if you'd just touched down on landing.
If X crosswind controls = zero drift on touchdown that's the expected, and desired, performance on liftoff.
It's a blend of technique and mechanical inputs. Boeing talks about 'smoothly'.
Mechanically? Rudder input will be greater than required aileron input(only enough to maintain wings level) while accelerating. At rotation more aileron will be require. How much? Think of your crosswind landing control inputs - if X rudder than give X aileron a try and make small(smooth) adjustments as you lift off and start your initial climb.
Smooth input as necessary, maybe a slight increase immediately prior to Vr to achieve correct cross control for zero sideload on liftoff, reduce rudder first to allow nose to turn into wind (equal to crosswind) to maintain runway track, and level wings on correct heading.
It's nice to see done correctly. If you've never flown with the other pilot before you'll have some insight to their ability by 100' on departure if there's a stiff crosswind. Hopefully it's and not 
.
(the slight increase in aileron is my opinion and no comment is made about it in Boeing statements)
If X crosswind controls = zero drift on touchdown that's the expected, and desired, performance on liftoff.
It's a blend of technique and mechanical inputs. Boeing talks about 'smoothly'.
Mechanically? Rudder input will be greater than required aileron input(only enough to maintain wings level) while accelerating. At rotation more aileron will be require. How much? Think of your crosswind landing control inputs - if X rudder than give X aileron a try and make small(smooth) adjustments as you lift off and start your initial climb.Smooth input as necessary, maybe a slight increase immediately prior to Vr to achieve correct cross control for zero sideload on liftoff, reduce rudder first to allow nose to turn into wind (equal to crosswind) to maintain runway track, and level wings on correct heading.
It's nice to see done correctly. If you've never flown with the other pilot before you'll have some insight to their ability by 100' on departure if there's a stiff crosswind. Hopefully it's
and not .(the slight increase in aileron is my opinion and no comment is made about it in Boeing statements)
Last edited by misd-agin; 15th January 2012 at 14:43. Reason: added last sentence
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From: nowhere
You are entitled to your opinion JammedStab
After some 20000 of PIC jet time with 5000 plus hours of Captaining the finest jet off the Boeing assembly line, the good old reliable 727 that is, I never had a near excursion or overrun on takeoff using my technique. The FAA was satisfied as well as I trained some of their folks too. At the end of the day, I guess what ever works...
My point is that one's attention during the takeoff roll should be out the window and not at the control column and provide the appropriate control input accomplish a successful wings level takeoff.
After some 20000 of PIC jet time with 5000 plus hours of Captaining the finest jet off the Boeing assembly line, the good old reliable 727 that is, I never had a near excursion or overrun on takeoff using my technique. The FAA was satisfied as well as I trained some of their folks too. At the end of the day, I guess what ever works...
My point is that one's attention during the takeoff roll should be out the window and not at the control column and provide the appropriate control input accomplish a successful wings level takeoff.
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From: nowhere
Are not posts #47 and #53 almost the same with the newer plane being perhaps a little less descriptive. Maybe you mean the 300 and greater series.
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From: 41S174E
You're right I do Jammedstab. Ta.
With that in mind, maybe it's not so much a 'type' thing as a time thing. Maybe around 2006 Boeing decided to change technique so that the roll started with the yoke centered and aileron was introduced to keep wings "approximately level" during the roll?
With that in mind, maybe it's not so much a 'type' thing as a time thing. Maybe around 2006 Boeing decided to change technique so that the roll started with the yoke centered and aileron was introduced to keep wings "approximately level" during the roll?
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From: Denver,Co USA
Boeing changes their manuals at least once a year plus different operators may have different wording and techniques in their manuals. At the start of takeoff roll there is no airflow over the control surfaces so it doesn't matter where the controls are. Once you start to roll you steer with the rudder and keep the wings level with the ailerons. If you maintain runway center line and lift off with wings level you did it right. After becoming airborne you will be in a slip. Gradually take out the cross controls and fly whatever heading or course you need. I don't know whether the starting position for small airplanes is important, but after you get rolling they all work the same.
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From: UTC +8
I don't pre set nor do I allow my F/O to pre set ailerons.
In the B747 training manual [published by Boeing] it says:
"To prevent spoiler drag early in takeoff roll, do not preposition aileron into the wind until wing roll is noted."
In the B747 training manual [published by Boeing] it says:
"To prevent spoiler drag early in takeoff roll, do not preposition aileron into the wind until wing roll is noted."
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From: Grobelling through the murk to the sunshine above.
The Boeing 737 (300-900) FCTM reference is quite a recent change, they are now on Revision 9, dated 30 June 2010.
Edition 7 had the 'old' guidance as follows (cut & pasted):
This was replaced in Revision 8, 31 October 2008, by the guidance given earlier, which is still the same in Revision 9:
This shows that techniques are constantly under revision, and referring to FCTMs dated 1985 is probably not the best way to keep your skills up to date. Likewise referring to other machine's training guidance is not wise.
As for the statement "all airplanes fly the same", that is clearly rubbish, although a university professor in aeronautical physics may put it that way, because the fundamentals of lift/drag/thrust/weight/bernoulli etc do not change. They may all fly by the same principles of physics, but their handling qualities can be vastly different.
Edition 7 had the 'old' guidance as follows (cut & pasted):
Maintain wings level during the takeoff roll by applying control wheel displacement into the wind. During rotation continue to apply control wheel in the displaced position to keep the wings level during liftoff.
Begin the takeoff roll with the control wheel approximately centered. Throughout the takeoff roll, gradually increase control wheel displacement into the wind only enough to maintain approximately wings level.
As for the statement "all airplanes fly the same", that is clearly rubbish, although a university professor in aeronautical physics may put it that way, because the fundamentals of lift/drag/thrust/weight/bernoulli etc do not change. They may all fly by the same principles of physics, but their handling qualities can be vastly different.
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From: nowhere
It sure would be interesting to find out why the change was made. I suspect that there is a discussion prior to making such a change.