Anti-torque control question

[rascalsailor]

Hi all
This a basic question - I did ask this in Spectator balcony, but received no reply)
I recently discovered a flight simulator (helisim) which I have enjoyed using. My question is regarding the effect of the pedals (anti-torque).

I always thought that if, for example, a helicopter was flying say North, that applying left pedal say, would cause both a heading change as well as a direction (course) change to the left. (i.e as though a giant hand had turned the whole arrangement including the cyclic pitch to now move forwards on a new heading to the left (west) of the old heading).
What I noticed is that the helicopter continues North according to the original cyclic pitch, but is now yawing (slipping) right.
Is this correct?
ta
Russell

[hihover]

Your own thoughts are almost right. In forward flight, pressing the left pedal would cause the helicopter to yaw left. It would also cause the helicopter to roll to the left. The rates of yaw and roll will depend on the rate of pedal application and forward speed. The result is ugly and stressful on the airframe.

I doubt a PC based simulator would replicate this adequately.

I hope this helps your understanding.

Tam

[Camp Freddie]

Rascal,

Just keep it simple
1) cyclic controls direction/speed
2) pedals control heading/balance

Turn in forward flight using cyclic
Use pedals in forward flight to maintain balance only

[Arm out the window]

The sim probably won't react like the real thing, but one factor is that a helicopter cabin is usually a big draggy box hanging from the rotor head.

If you use pedal to yaw left, say, the relative airflow on the fuselage is coming from the right. Now the rotor head is trying to drag that cabin along while it's cocked off to the left, and the result will be a tendency to roll to the right.

The effect is particularly pronounced in a teetering head helicopter with fixed floats (ie heaps of drag surface down low, and also more forward than usual, reducing the longitudinal stability). If you yaw one way, there's a big roll the other way so it will wallow along like a big pig.

[HeliComparator]

If its a reasonably sophisticated helicopter with decent autopilot, the previous replies aren't really correct because the autopilot will mask these basic effects. What I would expect to happen (hands off the cyclic) is that the aircraft yaws, but with minimal change in roll or pitch attitude. Initially the track will remain as it was, but the force of the air hitting the side of the heli will gradually change the track until it is the same as the heading (assuming no wind). You would initially see a large deflection in the slip ball representing the lateral acceleration (ie rate of change in track) but this would gradually subside as the track came closer to the heading.

[rascalsailor]

Thanks for all the replies,
that helps a lot
Russell