llApplyImpulse() for a choppers "rudder"

ive been playing around with this idea for a week or so now and i thought i had it right but the chopper dosent agree with me lol. the rudder is based on speed if you under 5 you will have a rudder if over 5 it will do the regular turning that ive scripted in. here are the parts im having trouble with. sometimes the impulses will work and other times i slow down and stop and the impulses wont turn the chopper

float myMass

//state_entry()

myMass = llGetMass()

//control

if ((level & CONTROL_ROT_RIGHT) | (level & CONTROL_RIGHT))
        {
            if(speed > 2.5)
            {
                turning = TRUE;
                adecayoff = TRUE;
                turn = .7;
                llSetVehicleVectorParam(VEHICLE_ANGULAR_MOTOR_DIRECTION, <turn,0,0>);
            }
            else if(speed < 2.5)
            {
                 turning = FALSE;
                 adecayoff = TRUE;
                 llApplyRotationalImpulse(<0,0,-.7> * myMass, TRUE);
            }
        }
        
        if ((level & CONTROL_ROT_LEFT) | (level & CONTROL_LEFT))
        {
            if(speed > 2)
            {
                turning = TRUE;
                adecayoff = TRUE;
                turn = -.7;
                llSetVehicleVectorParam(VEHICLE_ANGULAR_MOTOR_DIRECTION, <turn,0,0>);
            }
            else if(speed < 2)
            {
                 turning = FALSE;
                 adecayoff = TRUE;
                 llApplyRotationalImpulse(<0,0,.7> * myMass, TRUE);
            }
        }

//turning()

        if(turning)
        {
            llSetVehicleVectorParam(VEHICLE_ANGULAR_MOTOR_DIRECTION, <turn,0,0>);
            turn = 0;
            turning = FALSE;
        }

//timer()

integer speed = (integer)(llVecMag(llGetVel()) * 1.94384449 + 0.5);

it seams to work now but ......

when i try to turn left 60% of the time it refuces to turn atall till i turn right