Is rudder required for coordinated turns?

In article .com,
"nrp" wrote:

Tom Young wrote:
On Tue, 19 Sep 2006 23:02:58 GMT, Jose ... wrote:
The only plane I know of that had interconnect is the Ercoupe.

Our '51 TriPacer (S/N 13) had rudder-to-airleron interconnects which we
hooked up before annual insp but tied off before anyone wanted to fly
it afterwards. I never understood why there was an interconnect.

When the Pie Chaser was certified (about 1951), interconnect was all the
rage among manufacturers, including Beech and Piper. Personally, I have
always found interconnect to give an objectionable feel to a plane. I
hate the extra load on the controls!

Jose wrote:
Dunno about the Mooney or Bo, but the Arrows I've flown do not have interconnect. You have full individual control of each of the three axis. What it =does= have is differential deflection of the alerons, which reduces adverse yaw. The only plane I know of that had interconnect is the Ercoupe.

I flew a 71 Arrow and it did have an interconnect.

Robert M. Gary writes:

It depends on the plane. High performance planes almost always have
rudder interconnect. Planes like Arrows, Mooneys, Bonanzas, etc
automatically move the rudder when you roll the ailerons.

Do you feel this in the rudder pedals? Also, do you still have
independent rudder control? That is, can you inhibit the automatic
rudder movement, or increase it?

I'll look at the sim aircraft on the ground and see if the rudder is
moving with the ailerons.

However, if the J-3 simulation acts that way, the sim developer doesn't know
what he's doing.

What is J-3?

--
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Yes. The rudder pedals move with aileron control inputs. And yes, they can
be moved independently of the ailerons due to the spring configuration. It
makes slipping down final in a crosswind a little more difficult since you
have the usual control forces due to aerodynamic pressure plus the pressure
applied by the springs. That's why I prefer to crab down final and
straighten out just before the wheels touch down. That's also easier on the
passengers.

A J-3 is a Piper Cub.

mike

"Mxsmanic" wrote in message
...
Robert M. Gary writes:

It depends on the plane. High performance planes almost always have
rudder interconnect. Planes like Arrows, Mooneys, Bonanzas, etc
automatically move the rudder when you roll the ailerons.

Do you feel this in the rudder pedals? Also, do you still have
independent rudder control? That is, can you inhibit the automatic
rudder movement, or increase it?

I'll look at the sim aircraft on the ground and see if the rudder is
moving with the ailerons.

However, if the J-3 simulation acts that way, the sim developer doesn't
know
what he's doing.

What is J-3?

--
Transpose mxsmanic and gmail to reach me by e-mail.

mike regish writes:

Yes. The rudder pedals move with aileron control inputs. And yes, they can
be moved independently of the ailerons due to the spring configuration.

So they move, but you can feel the movement and override it if you
want? I guess that's okay. I have an aversion to true fly-by-wire
systems, but if you know what it's doing and you can override it, it's
probably still safe.

It makes slipping down final in a crosswind a little more difficult since you
have the usual control forces due to aerodynamic pressure plus the pressure
applied by the springs. That's why I prefer to crab down final and
straighten out just before the wheels touch down. That's also easier on the
passengers.

The crabbing technique is the only one I've tried in the sim thus far.
It was impossible with just a keyboard; adding a joystick made it
possible, although it's not easy.

A J-3 is a Piper Cub.

Thanks.

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Mxsmanic wrote:

Is it always necessary to use the rudder to execute a coordinated
turn? When I turn (in simulation) it seems that just rolling the
aircraft suffices, as long as the bank angle isn't too steep. (And
no, I don't have automatic rudder control enabled.)

What plane are you using? If I turn off auto rudder control with the
Cessna 172, the little ball is all over the place.

Marc

Marc Adler writes:

What plane are you using?

I've been flying the Baron 58 and the 737 from the stock game, plus
the Dreamfleet Bonanza A36 and the PMDG 737-800. In all cases,
standard, gradual turns don't seem to require much rudder input, even
with auto rudder control turned off.

I did look at the A36 from the outside while moving the stick, and the
rudder doesn't move. So presumably the loose connection that the real
aircraft has between ailerons and rudder is not being simulated, but
I'm not really sure (it could be simulated without the video, although
that's unlikely--or it could be so gentle that it's hard to see
movement in the rudder).

If I turn off auto rudder control with the
Cessna 172, the little ball is all over the place.

I see the ball move occasionally, but not much. I tend to make
gradual turns, though, especially in large aircraft. (Remember that I
flew MSFS with just a keyboard for 15 years, and that teaches you to
be gentle.)

--
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Mxsmanic wrote:

I see the ball move occasionally, but not much. I tend to make
gradual turns, though, especially in large aircraft. (Remember that I
flew MSFS with just a keyboard for 15 years, and that teaches you to
be gentle.)

I always fly out of one airport (KAUS) with the weather set to
real-time and the time of day the current time of day (because that's
the airport where (I'm assuming) I'll learn to fly), so maybe the wind
conditions affect performance, because even on level flight the ball in
the inclinometer is hard to keep in place.

Incidentally, speaking of input devices, do any people here who use a
yoke* and who also actually fly think the yoke is more realistic (and
therefore worth the price tag) than the joystick?

Marc

*e.g.:
http://www.pilotshop.com/flight-yoke...4bf5edfca0c21b

"Rudder" is required to make coordinated rolls into banks in most aircraft.
The next question would be: is the rudder applied automatically by the
movement of the lateral controls? If not, then the pilot may have to
displace the rudder himself. Some aircraft have rudder input applied
automatically when the control column/stick is displaced.

One example of that is the B-58 which has a rudder/elevon interconnect which
uses a computer to determine when, if, how much, and in what direction the
rudder should be moved when the pilot makes a lateral input to the elevons.
In subsonic flight the rudder is normally displaced in the same direction as
the lateral input. In transonic flight the shock wave hits the vertical
stabilizer producing a "rudder" force which has to be corrected. At some
speeds the rudder is actually moved in the opposite direction since the
shockwave force on the vertical stabilizer produces more "rudder" input that
is desirable. The automatic rudder input changes more as the aircraft
accelerates to mach 2.

The B-52 is different also, in that the H model (that I flew) has no
ailerons and uses hydraulic spoilers on the top of the wings to produce the
required roll input. With no speed brakes deployed a roll input causes the
spoilers on the downward moving wing to be deployed, spoiling lift and
dropping the wing. The resultant drag makes a rudder input in that
direction to not be required. Because the spoilers are aft of the center of
lift, deploying a spoiler on a clean wing also causes an undesired pitch up.
In the traffic pattern speed brakes are normally deployed to an intermediate
position. In this case a roll input to the left will cause the left
speedbrake/spoilers to rise further and the right speedbrake/spoilers to
lower somewhat. This about eliminates the pitchup and makes flying more
stable.

That said, most aircraft require a pilot input of rudder to coordinate a
roll input. Little, if any, rudder is required once the roll stops and a
constant bank is maintained. Fancier aircraft have yaw dampers which also
reduces the required pilot rudder input. So, to answer your original
question it is necessary to change your question somewhat. Change the word
"turns" to "rolls", since most rudder coordination is necessary only while
rolling into a bank and little is needed once bank is established to further
coordinate the turn while bank stays constant. In light aircraft the amount
of wing dihedral can affect turn coordination.
--
Darrell R. Schmidt
B-58 Hustler Web Site URL (below)
http://members.cox.net/dschmidt1/

"Mxsmanic" wrote in message
...
Is it always necessary to use the rudder to execute a coordinated
turn? When I turn (in simulation) it seems that just rolling the
aircraft suffices, as long as the bank angle isn't too steep. (And
no, I don't have automatic rudder control enabled.)

--
Transpose mxsmanic and gmail to reach me by e-mail.

Mxsmanic wrote:
mike regish writes:

Yes. The rudder pedals move with aileron control inputs. And yes, they can
be moved independently of the ailerons due to the spring configuration.

So they move, but you can feel the movement and override it if you
want? I guess that's okay. I have an aversion to true fly-by-wire
systems, but if you know what it's doing and you can override it, it's
probably still safe.

You can feel it slightly. However it takes very little effort to
override it by pressing the rudder. Actually, in my Mooney is gives a
bit too much rudder such that I give a little bit of outside rudder
when I roll into a turn.

This works the same as your Cessna nosewheel vs rudder. On the ground
the rudder on the Cessna is a little harder to press because you are
moving the tire against the pavement but you can still get rull
deflection of the rudder.

-Robert