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How Do You Make A Coordinated Turn In An Airliner?

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Since there aren't any turn coordinators in modern airliners such as the 747, how do you know how much rudder you need during turns when flying these beasts?

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Since there aren't any turn coordinators in modern airliners such as the 747, how do you know how much rudder you need during turns when flying these beasts?
The banking portion of the turn coordinator is used to tell if you are making a standard rate turn, which is three degrees per second. It is the slip/skid ball portion that tells you whether you are using the correct amount of rudder. Airliners, even 747s, have slip/skid balls. Some are mechanical like the one in the turn coordinator, some are digital and part of a graphical display. The turn coordinator as you know of in the piston planes is unncessary in a jet since there is no reason to make standard rate turns in jet flying. But the slip/skid balls are used in jets. And that is the only part that tells you whether your turn is coordinated or not.
Do you even NEED rudder to turn a jet? :(
Yes, you do.

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So where is the turn coordinator located in a 747-400 cockpit?

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It is part of the Bank indicator. The bottom half will slide left or right to indicate a Skid or Slip.pfdcapt.jpg

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So where is the turn coordinator located in a 747-400 cockpit?
There is no "turn coordinator" in the 747-400 or most any jet. There is however, a slip/skid ball, as joeairplane79 has already posted a picture of. The "turn coordinator" in GA aircraft is an instrument that consists of both a turn rate indicator and a slip/skid ball, combined together in one instrument and normally mounted at the bottom left of the panel. This "turn coordinator" is a piston general aviation instrument and not used on jets. However, rudder coordination is just as important in a jet, so the slip/skid ball is featured prominently in jet aircraft, usually mounted as part of your attitude indicator, either as a mechanical ball beneath the artificial horizon or a graphical one in the tv screen. The turn rate indicator, the part of the "turn coordinator" that shows whether your turn is three degrees/second or not, is not needed in a jet and is dispensed with. Hence there is no "turn coordinator", but there is definitely a slip/skid ball in the jets.

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Thanks, I think you guys have answered my question!

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I just thought I'd add to this to let people know why the turn-coordinator is missing in jets. It has to do with speed. At the speeds jets typically fly at, the bank required to make a standard rate turn exceeds 30 degrees of bank, which is the legal limit in the US for an aircraft carrying passengers.

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I recently flew a 737-800 full motion sim down in Houston, and my sim instructor told me to fly with my feet on the floor and not to even touch the rudders when I was in the air. I asked him why, since I'm used to flying single and twin-engine pistons. He said that as long as the yaw damper is on you really don't need to touch the rudder at all, even in a steep turn. It was a little weird taking off and then as soon as the gear was up, my feet were on the floor. It was an interesting aspect of flying a jet I never thought of.

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I recently flew a 737-800 full motion sim down in Houston, and my sim instructor told me to fly with my feet on the floor and not to even touch the rudders when I was in the air. I asked him why, since I'm used to flying single and twin-engine pistons. He said that as long as the yaw damper is on you really don't need to touch the rudder at all, even in a steep turn. It was a little weird taking off and then as soon as the gear was up, my feet were on the floor. It was an interesting aspect of flying a jet I never thought of.
That's a pretty bad technique. We have checkairman here who would dequal you if they see you leave your feet flat on the floor like that. Sure, as long as your yaw damper is on and all your engines are spinning, you won't need to make much input on the pedals as the yaw damper acts like an autorudder. However, that does not mean that jet aircraft do not need rudder inputs as other planes do, it is just that your yaw damper does it for you. A jet aircraft needs to spend money on devices like that since if the rudder is used improperly, the aircraft can swing out of control due to dutch roll, which makes a rudder even more important than on a prop aircraft. Don't confuse the fact that a working yaw damper device is doing the rudder work for you with the notion that a plane does not need rudder work.

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