What do gravel, mud, sand, tall grass, deep snow, slush, standing water, and all other rough surface conditions have in common? Well, if we’re talking about runway surfaces, these all translate into soft-field operations. Whether you’re a student pilot preparing for your checkride or a seasoned pilot with thousands of hours of experience, soft-field skills should be routinely practiced.
Soft-field takeoffs and landings are two of the most demanding skills for pilots to master, and for good reason. Their mastery demands that the pilot have complete control of the aircraft’s attitude, flight path, speed, and directional control right down to—and even below—its stall speed. This requires complete coordination of all the flight controls, especially at the slowest airspeeds where precise aircraft control is the most challenging.
There are two primary reasons that necessitate soft-field operations: The physical nature of the runway’s surface could damage the aircraft at normal takeoff or landing speeds, or the surface is composed of—or covered by—a material that would generate such high drag that normal operating speeds would be either unattainable or undesirable. Whenever these conditions exist, the pilot in command must recognize that a soft-field operation is called for and take the appropriate actions necessary to accomplish it safely, minimizing the aircraft’s exposure to the hazards presented by the runway’s surface conditions.
Let’s assume you have just waited out a passing thunderstorm that has left several large areas of standing water on your planned departure runway. After first determining that a departure delay or runway change are not feasible options, you correctly decide to prepare for a soft-field takeoff, since a normal takeoff speed may not be achievable because of the added drag and slow acceleration that will result from the standing water.
Aircraft manufacturers provide checklists and specific flap configurations for soft-field takeoffs, so check your pilot’s operating handbook for the specifics. Typically, manufacturers will recommend that partial flaps be extended, as this will allow the wings to produce more lift earlier in the takeoff roll, which in turn yields a slower liftoff speed. But if your POH does not address soft-field operations, refer to the FAA’s Airplane Flying Handbook for additional guidance.
Besides the added flaps, another detail that makes this procedure different from a normal takeoff is that you should begin your takeoff roll with the control yoke fully back (up elevator), or nearly so, as you begin to smoothly add full power. Be careful not to add power so rapidly that any loose gravel or stones could be picked up and knick your propeller. Holding up elevator will provide for the earliest possible pitch increase to a best angle of climb (VX) pitch attitude as the aircraft accelerates down the runway.
Keep in mind that as power is advanced, the prop wash will cause the elevator to quickly become very effective. So to prevent an overrotation and resultant possibility of striking the tail on the surface, be prepared to promptly adjust the amount of elevator control deflection necessary to obtain and hold the desired VX pitch attitude. Once the nosewheel is off the surface, you simply maintain that climb attitude as you accelerate. The beauty of this is that even while you are still moving too slowly to fly, the wings will be gradually producing more and more lift as you accelerate until liftoff finally occurs automatically once you achieve the proper speed—and away you go.
Another big difference from a normal takeoff is that once the nosewheel is clear of the runway, you’ll be presented with a very different-than-normal sight picture as you attempt to accelerate the aircraft down a now-invisible runway centerline. A byproduct of the nose-high attitude is that additional (left-yawing) P-factor forces will be generated at a time when you’ll have zero nosewheel steering capability. However, rest assured that your rudder is still very effective at maintaining alignment with the runway centerline.
To ensure proper runway tracking, however, you must be sitting up high enough in your seat to maintain a visual reference to the runway’s surface throughout your entire takeoff roll. Remember, you must be able to see the runway if you wish to stay on it. With the runway’s edge still in sight, simply press the rudder pedals as needed to keep the aircraft rolling down the runway as you simultaneously deflect the ailerons as necessary to correct for any crosswinds that might be present. Too frequently, National Transportation Safety Board accident reports illustrate what happens when pilots lose directional control during takeoffs. Proper directional control is absolutely essential for all takeoffs. It’s just a bit more challenging to maintain during a soft-field takeoff, especially in crosswind conditions.
Once the aircraft lifts off the runway, you must be aware that your airspeed is only slightly above the stall speed. A continued climb above the area of ground effect at this slow an airspeed could result in settling back to the runway or, even worse, an aerodynamic stall at a hundred feet. To prevent this, as liftoff occurs, you must be prepared to quickly but very smoothly re-adjust the pitch attitude as necessary so that the aircraft maintains an altitude only a few feet above the runway while you accelerate to the appropriate climb speed—either VX if obstacles are ahead, or best rate of climb (VY) if the departure path is clear. Once the appropriate climb speed is attained, begin your climb away from the runway, retracting the landing gear (if appropriate) and waiting until a safe altitude is reached before retracting the flaps and transitioning to a normal climb. Do not rush this final step. Remember that it’s way better to retract the flaps a little late than while you’re still too low and slow.
Reversing the process
Now let’s suppose you’re approaching a runway that requires a soft-field landing. The primary objectives in a soft-field landing are to ensure that the aircraft contacts the runway at the minimum forward speed and at the minimum descent rate— in other words, the softest possible touchdown at the slowest possible speed.
Naturally, all pilots strive to make every landing a “greaser,” but during soft-field operations, that is an essential element of the landing maneuver. This usually means (per POH) a full-flap landing, since full flaps will produce a slower stall speed. It also means a stabilized approach at the desired approach speed and at a normal approach angle of about three degrees. Translated, a normal three-degree approach path means about 1,000 feet of altitude for every three miles flown, or 333 feet above the ground on a one-mile final approach. Achieving this approach angle usually will require you to fly a power-on approach, because a power-off approach would result in an undesirably steep approach angle and high descent rate with full flaps. For these types of power-on approaches, I prefer to control airspeed with power and fine tune the desired approach path with the elevator control on final approach, but this is just a technique. Try it, you might like it.
So far, it’s a fairly normal, full-flap approach. The main difference occurs when you begin the flare. Assuming the runway length is not an issue (short-field landing), instead of reducing power to idle as you would during a normal landing, you should either maintain or even add a bit of power as you begin the flare. This will stretch the amount of time you have in the flare as you gradually slow toward stall speed. In other words, this is a power-on approach and a power-on landing.
Because your objective is to touch down at the minimum forward speed, as you flare and the airspeed decreases, keep flying just inches above the surface for as long as possible until you can ensure a silky-smooth touchdown, either at or just above stall speed, all while keeping the nose aligned with the runway centerline using rudder and eliminating any side drift with aileron inputs.
Remember that brakes are seldom needed to slow down, since a soft or rough surface usually generates more than adequate deceleration forces. As soon as the main wheels touch the runway, be prepared to adjust power as necessary to yield a safe deceleration rate. Depending on available runway length and surface conditions, this could mean reducing, maintaining, or even increasing power. This is an important judgment call you’ll need to make based on the actual surface conditions, so be ready for it.
As you adjust your deceleration rate with power, also remember to continue applying up elevator control as necessary to hold the nosewheel off the runway for as long as possible and then smoothly fly the nosewheel down to the runway—before elevator control is lost. Do not allow the nosewheel to firmly drop onto the runway. Holding the nosewheel off the surface is critical for two important reasons—first, to prevent the nosewheel from becoming an anchor that might cause the aircraft to flip over on its back; and second, because keeping the nose up during the landing roll also allows the wings to gradually lose their lift, which provides a more gradual and safer transfer of the aircraft’s weight to the runway surface.
Finally, remember that whenever you are taxiing on an especially soft surface, you may have to use higher-than-normal power settings to prevent the aircraft from bogging down and becoming stuck. Keep the aircraft moving at a safe, steady taxi speed by adjusting your power while maintaining full up elevator control to protect your nosewheel and propeller from damage.
You don’t have to be a witness to very many checkrides to realize that soft-field operations continue to be one of the toughest and most challenging tasks that pilots face. But whether you’re getting ready for your checkride, preparing for your flight review, or simply sharpening your stick-and-rudder skills, with a bit of quality practice you’ll be able to master the skills necessary for this critically important operation. The keys to your success are practice, practice, and practice.
Bob Schmelzer is a Chicago-area designated pilot examiner and a United Airlines Boeing 777 captain/line check airman. He has been an active flight instructor since 1972.
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