How to fly: Soft Field Takeoff 2 weeks ago

Now we’ll be doing a soft field takeoff. What is a soft field? A soft field is a runway/taxi surface that is grass, water, snow, mud, loose dirt, soft gravel, and so on. This kind of surface acts as a glue to the tires and prevents from the aircraft from accelerating at a normal rate.

Additionally, protecting our propellor is key. Ofttimes these types of airports also have the potential for potholes, ruts, gopher holes, etc. If our nose wheel was to drop into one of those holes with a good amount of weight on it, it could cause it to dip into the hole or rut, and cause a prop strike. That’s a big, expensive and dangerous mistake.

When operating on a soft field, we don’t come to a stop. If we need to do our runup before, we get that done. But once we start moving onto the runway, we stay moving. Even during the taxi you’ll add back pressure on the yoke. The slipstream of the propellor causes enough effectiveness on the elevator that this actually does take quite a bit of weight off of the nose wheel.

Now moving into takeoff position, and with one notch of flaps, we smoothly add full power while still holding back on the yoke.

During this takeoff roll we’re going to be actively flying the airplane even though we’re not airborne yet. With all that power, and with that yoke back, we’ll have not only a lot of need for right rudder, but we can vary the pitch.

We want to find a pitch angle, or angle of attack, that is going to get our nose wheel off the runway. Pull back TOO much and you’ve not created too much drag, and you won’t become airborne as fast as you could. So you’ve gotta find that sweet spot.

Because we already have back pressure on the yoke with a higher angle of attack, and that nose wheel is already off the runway, we’re going to become airborne before the aircraft is really ready to fly. The good news is we have a friend to help us out. That friend is Ground Effect.

Ground effect is a cushion of air, most effective about 1/4 wingspan above the runway, where our induced drag is drastically decreased. In other words, we can ride this cushion, fly at a slow speed, and gain the energy we need to climb out.

So as soon as the airplane becomes ‘unstuck’ from the ground, you’re going to release some of that back pressure and accelerate VERY close to the runway. Literally, a few feet. Don’t touch back down, but get as close as you practically can. The closer you get, the more effective that ground effect.

Once you’re at Vx or Vy, transition out of ground effect, climb as normal, clean up the airplane, and continue onward.

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