Airplane Soft-field Takeoff and Landing

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Soft-field takeoff and landing techniques are used to get into or out of fields made soft by mud, snow, tall grass, or even just wet grass. And this technique is also very good for fields where the surface is rough. In fact, soft-field procedures are used almost anytime you are not using a smooth, hard-surfaced runway.
Soft-field takeoff
For a soft-field takeoff, set your flaps as per the manufacturer’s recommended flap setting. (Many low-wing aircraft manufacturers recommend using no flaps since the flaps on low-wing aircraft are very close to the ground and can easily be damaged by mud, rocks, etc.) Since the surface is soft, it is very important that once you start your aircraft moving, you keep it moving. Even taxiing should be done with full aft yoke to offset any noseover tendency.

The pilot’s first concern during the soft-field takeoff is to transfer the weight from the wheels to the wings as rapidly as possible. The flaps help do this, but at the start of the takeoff run, you should have the yoke full back to help lift the nosewheel off of the ground and reduce the drag created by the soft field. Since this technique gives you a much higher angle of attack than other takeoffs you have been used to, once the nose begins to come up, you must be prepared to relax a bit of the backpressure so you don’t smack the tail into the ground. That is very easy to do, and the loud bang the tail makes as it strikes the runway usually scares a pilot into shoving the stick forward, sometimes a bit too far. The nosewheel might then get swallowed up by the soft surface you
are trying so hard to get out of.

Once you have the nose at the desired attitude and are rolling down the runway, keep the nose attitude constant until the aircraft is off of the ground. The liftoff should occur at a much slower-than-normal airspeed because of the high angle of attack. For this reason, once the aircraft becomes airborne, the angle of attack must slowly and smoothly be reduced to near-level flight attitude as the aircraft accelerates toward the normal climb speed. You should maintain the near-level attitude, in ground effect, until you reach your nominal climb speed (either Vx or Vy, depending on whether or not there is an obstruction to be cleared).

After accelerating in ground effect to the desired speed, a normal climbout should be initiated and the flaps brought up once established in a climb. Don’t be in a hurry to bring up the flaps. They are providing lift, and if brought up too soon, they could cause a momentary sink that could lead to trouble.

One other important point concerning soft-field takeoffs, or any takeoffs for that matter, is to be sure you lift off and maintain a straight track down the runway. If you have a slight crosswind, resist the tendency to crab into the wind as soon as you lift off. If the wind were to die, you could settle back to the runway in a crabbed configuration, and the result could be one of the shortest flights on record. Use the wing-low sideslip method mentioned earlier for crosswind takeoffs and landings. Keep your aircraft in this sideslip while heading straight down the runway and until you are positively airborne.

Soft-field landing
The approach to the soft-field landing should be made at normal approach speed. The touchdown should be as slow as possible in order to minimize the noseover tendency. Unless you are in a low-wing aircraft and the manufacturer recommends no flap landings in a soft field, this usually means an approach and landing with full flaps. The touchdown should be with flaps as recommended, full stall, and full back stick. A small amount of power can be used in the flare to help bring the nose up and provide the momentum necessary to prevent a noseover.

Keep the yoke in the full-back position during the rollout and be ready to use power to help you through any really soft spots like snow drifts or deep mud. When you are safely on firm ground and slow enough to taxi, you can take the carb heat off and bring up your flaps. Use caution as you taxi.

An important item to remember during the conduct of soft-field operations is that it is nearly impossible to judge when snow or mud get deeper. All one can see is the top of the surface and there is no way of knowing where the drifts or sinkholes begin. Soft-field operations should be handled with great care and forethought, not with haphazard preparation or spontaneous whims.

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