Controlling P-factor and yaw during takeoff and climb

You have completed your walk-around the airplane to your instructor’s satisfaction, taxied to the active runway, performed a pre-takeoff check and engine run up. The tower told you to taxi onto the runway and line up for takeoff.

Your instructor has been working the radio for you but otherwise you are handling all of the tasks.

With a “Okay, let’s go.” You smoothly push the throttle as far forward as it will go. The airplane’s acceleration pushes you back in your seat as you start down the runway.

There is a slight crosswind from the left. Your instructor tells you to use a little left aileron to compensate for it. The wind blowing against the left side of the tail and rudder combined with P-factor causes you to start turning slowly to the left. Your car-driving instincts take over and you start steering with the wheel. You turn the wheel to the right with no effect at all. This has you a bit excited.

She calmly says, “Use your feet to point us down the runway and turn the wheel back to the left.” You’re now definitely on the left half of the runway. You start to bring the plane back into the middle when she says, “Don’t worry about that. Just keep us pointed straight.” As you continue to accelerate you monitor the airspeed indicator (ASI). When you reach rotation indicated airspeed (Vr) you pull back on the elevator to raise the nose wheel off the runway.

A few seconds later, you’re climbing. The crosswind carries you off the runway to the right. She says, “Try to stay over the extended runway centerline until you decide to turn crosswind. Look over your left shoulder at the runway. You can see that you’re to the right of the extended centerline.”

You execute a shallow turn to get centered on the runway. She says, “In a small airplane like this, we usually climb at best rate of climb airspeed (Vy). In this airplane, it’s 64 KIAS. But to keep things simple, let’s say 65. Using what you learned in the last lesson, you make a series of small adjustments to your pitch attitude until you are stable at 65. But you don’t notice that you’re flying in a right wing low attitude.

She smiles and chides you gently, “Probably 90% of pilots climb without compensating for P-factor. Ordinarily it is no big deal but it’s a bad habit to get into. In some circumstances it can be quite serious. So let’s try to nip it in the bud.

“Remember to keep your wings level with your ailerons and keep the nose from yawing with your rudder.” You look at each wing tip to verify that they are both the same distance from the horizon. Sure enough your right wing is lower than your left by probably not more than a few degrees … but noticeable. You level your wings and the nose starts to slowly wander to the left requiring a bit of pressure on the right rudder pedal.

Now that you’ve got your wings level and have stopped the nose from yawing, you’re starting to feel pretty satisfied when she tells you that your airspeed is too high and you are no longer climbing.

She says, “Remember to look over the nose at the horizon. You can tell if your wings are level if the top of the nacelle is parallel with the horizon. You can tell if you’re turning just as easily by looking straight ahead as in any other direction.

“You want to change your pitch attitude by looking over the nacelle, making a small adjustment… in this case, up… then holding the pitch steady while occasionally glancing at your airspeed to see if you’ve got it where you want it.

“Once the airspeed is steady at 65, trim the pressure out of the elevator while looking forward to ensure that the pitch attitude does not change. Okay?”

For the first few minutes you find that when your airspeed is under control, your heading drifts. Then you get back on course and your airspeed is too low or too high. That’s normal. Within the first five minutes you’ve got them both under control.

In the next post, I’ll show you just how important compensating for P-factor can be. For me, this is an emotional issue. You’ll see why. Look for ‘P-factor Effects can be very Serious.’

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