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Do pilots use rudder during turns on the 747?

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Do pilots use rudder during turns on the 747?

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Old 15th June 2008 | 17:10
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Do pilots use rudder during turns on the 747?

Might sound a strange question, but assuming manual flight at altitudes of say 3,000 to 10,000 ft (therefore not approach or high altitude cruise), would the pilot put rudder in during a turn or do the Yaw Dampers take care of that?

Thanks.
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Old 15th June 2008 | 17:16
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Yaw damper does it all
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Old 15th June 2008 | 17:33
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From: The No Transgression Zone
Correct, me if I'm wrong but I believe that the flight control logic-automatically--coordinates the turn in the 747--2,3,4??
Via the YD system???--as Mini Jumbo explained

Lovely Ship

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Old 15th June 2008 | 17:42
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Yes, correct. Does a perfect job.
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Old 15th June 2008 | 18:02
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Just like a Tri-Pacer!
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Old 16th June 2008 | 09:50
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Technically turn coordination only takes place with flaps down. With flaps up, the yaw damp function works. However, the airplane flies nicely enough that it's nearly a feet on the floor airplane. With the autopilot engaged, it's a two axis airplane; there's no cordination through the yaw damper except after flaps are extended. However, even though the autopilot has no rudder input, it flies around a turn just as nicely as if it did.
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Old 16th June 2008 | 10:59
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From: Standing at P37
General Description and Operation of the Yaw
Damper System
An electro-hydraulic yaw damper in each rudder PCU is used to
dampen aircraft oscillations or (dutch roll) about the vertical axis.
The series yaw damper signals for the rudder actuators is fully active
for takeoff, cruise and landing. With this system, the rudder pedals
are not displaced. The system includes two computers, inboard and
outboard flaps UP limit switches, two rudder power control units, the
pilot and copilot attitude director indicators, the flight control surface
position indicator and the yaw damper control and test switches.


Turn Coordination
The 747 yaw damper also provides turn coordination. It operates the
rudders proportional to the Aircraft roll rate, sensed by the Yaw Rate
Gyros in the Yaw Damper Computers, to improve roll control
response when flaps are extended on the 747–200/300 Aircraft. On
the 747SP Aircraft the Turn Coordination function is active at all
times (No Flap input) and controlled by the Aircraft Airspeed (ADC
Input), and Aileron CCA output transducers.

Computers
Two computers are located in the main equipment centre. Each
computer contains a rate gyro and electronics to monitor and correct
aircraft oscillations or dutch roll.

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Old 16th June 2008 | 18:54
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From: cloud 9
Pilots don't, but the aircraft does!
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Old 16th June 2008 | 20:05
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From: Hampshire, UK
You don't mess around with the rudder on these big jets (unless you really have to). You will have everybody queueing for the rear toilets off their feet like a load of skittles. And when the stewardess picks herself up from under her trolley and bursts into the flight deck, what is she going to say? Think....headache, pre-menstrual, angry....what words do they use?

You leave your feet on the floor!
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