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Flight Performance - Level 3

Airplane Performance-Section 7

LANDING PROCEDURE

On approach to destination, contact the air traffic control (ATC) facility that is appropriate for that airport several miles outside the boundaries of the control zone, etc. If an ATIS broadcast is available, listen to it first and note the information. Follow the instructions of the control facility.

If the airport has no control facilities, but does have a designated mandatory frequency (MF) or aerodrome/airport traffic frequency (ATF), report on the MF or ATF just before you reach the specified area and again when you have joined the traffic circuit.

If the airport is uncontrolled and has no published MF or ATF, keep a careful watch for other traffic and monitor 123.2 MHz and report your own intentions on this frequency. Observe the wind T or windsock and note the direction of traffic. Conform to the standard procedure for traffic circuits at uncontrolled airports.

Be sure, before beginning your descent towards a landing, that you have given full consideration to conditions which might affect the landing: proper approach speed, gross weight and centre of gravity, density altitude, wind direction and velocity and gustiness, runway conditions, runway slope.

POST-FLIGHT INSPECTION

A post-flight inspection is a recommended practice for small airplanes as well as for large ones.  Mechanical deficiencies which arise during a flight can best be identified and attended to at the completion of the flight.  It is an ideal time to check the condition of the airplane, noting signs of strain or wear.

Your experience during the flight may indicate other potential trouble areas. Excessive fuel consumption may indicate a problem with the seating of the fuel caps, with the fuel drains or line fittings. Look for oil drips if the oil consumption was high. Check out any other condition that was abnormal during the flight.

BRAKING TECHNIQUE

Excessive braking shortens the life of the brakes and the aircraft tires. Therefore, airplanes should not be taxied at excessive speeds with unnecessarily high throttle settings that require use of brakes to maintain control.

Excessive landing speeds also result in accelerated tire wear and increase the possibility that excessive braking may be required to bring the airplane to a stop. If you have landed with too much speed and the tower then calls for a short turn off or if the runway is short or if a vehicle or airplane unexpectedly enters the runway, heavy braking will be required to comply with the situation.

Don't begin to brake as soon as you touch down. Right after touchdown, the airplane is still producing lift and the application of brakes has no effect on slowing the airplane. Aerodynamic drag is the major factor in slowing the airplane in the first quarter of its speed decay. Brakes become increasingly effective as airspeed and lift decrease. Once the airplane has slowed to at least 75% of its touchdown speed, rolling friction and the use of brakes will bring the airplane to a stop.

Form the habit of landing at the proper recommended speed and touching down at the end of the runway so that excessive braking will not be required.

Braking is reduced by sliding wheels. In addition, directional control is jeopardized. During braking, take care not to lock the wheels. Braking effectiveness drops significantly in a skid. To make matters worse, tires can be easily damaged in a skid.

Braking action is virtually non-existent on wet sod or wet runways or on frosted or icy runways. Landing rolls will be substantially increased under such conditions when brakes can be expected to be ineffective.

LANDING ERRORS

    WHEELBARROWING

Low wing airplanes with steerable nose gear are most susceptible to the pilot error of wheel-barrowing, although any tricycle gear airplane can be put into this unfavorable attitude.

It occurs when the pilot has inadvertently thrust too much weight onto the nose wheel. Loss of directional or braking control is the usual result.

Wheel-barrowing usually occurs when the pilot uses excess speed while making an approach in a full flap configuration. He may, in this situation, touch down with little or no rotation and then may try to hold the airplane on the ground with forward pressure on the control column. As a result, the main wheels are carrying insufficient weight for normal braking response. In winter, when snow or ices make the runway pavement more slippery than usual, the problem is compounded.

The chief cause of wheel-barrowing on take-off is the tendency to hold the airplane on the ground with forward control of pressure in order to build up a faster than normal groundspeed before rotating.

    BALLOONS AND BOUNCES

Sometimes in the final stages of the approach, the pilot has the sensation that the ground is coming up faster than it in fact is. He increases the pitch attitude too rapidly and causes the airplane to climb instead of descend. This climbing during round out is known as ballooning. It is also caused when the flaps are lowered too late in the landing sequence.

A bounce will almost certainly occur if the round out is made too slowly or too late so that the nose gear (in the case of tricycle geared airplanes) or the main gear (in the case of tail wheel airplanes) touches first. A bounce will also occur if the round out is completed too high and the airplane is dropped onto the runway.

A bounce or a balloon each produces a critical situation. Not only is the airplane gaining height above the runway but it may also be approaching a stall. As well, the cross wind correction may have been lost and the pitch attitude of the airplane may be in excess of that of the normal landing attitude.

The best corrective action for a severe balloon or bounce is to apply power and execute a go around. If the balloon or bounce is low in height and the pitch change is not extreme and there is sufficient runway left, a landing may be made by establishing directional control, applying power to cushion the landing and adjusting the pitch attitude to that landing attitude proper for touchdown.

    PORPOISING

Porpoising is the name given to the condition in which the airplane bounces back and forth between the nose wheel (or tail wheel) and the main gear after touchdown. It occurs most frequently as a result of an incorrect landing attitude and excessive airspeed that results in the nose wheel coming in contact with the runway before the main gear.

The porpoise may become progressively worse resulting in violent unstable oscillation of the airplane about the lateral axis that can damage the landing gear and the airplane structure.

The best corrective action is to smoothly use the controls to establish the normal landing attitude and add power to get the airplane airborne again. If there is sufficient runway left, land. Otherwise, go around again.

    HYDROPLANING

Hydroplaning is a condition that can develop whenever a tire is moving on a wet surface. The tire squeezes water from under the tread generating water pressures which can lift portions of the tire off the runway and reduce the amount of friction the tire can develop. On a runway contaminated by rain or wet snow, it can be impossible for an airplane to accelerate to take-off speed and then to stop on the remaining runway in an aborted take-off. During landing, deceleration and stopping an airplane can be similarly compromised.

There are three types of hydroplaning.

Viscous hydroplaning occurs when there is a thin film of water and relatively low tire speeds. The water lubricates the surface and decreases traction. A water film of only a tiny fraction of a centimeter will drastically reduce the friction between the tire arid the pavement and double the stopping distance.

Dynamic hydroplaning requires deeper water and results in complete loss of tire contact with the pavement. The tire lifts off the runway and rides on a wedge of water.

Reverted-rubber hydroplaning can occur when a locked tire skids on a wet or icy runway. Frictional heating raises the tire temperature causing rubber particles to shred off the tread. These particles accumulate behind the tire forming a dam that blocks the escape of water. The trapped water heats and turns to steam. The steam pressure lifts the tire from the surface.

    GO AROUND / OVERSHOOT

A go around, or an overshoot (the two terms means substantially the same thing), is a basic flight maneuver to be used when it becomes inadvisable to continue a landing approach. It should be the pilot's obvious choice of action when there is interfering traffic or when the landing procedures (flare, cross wind correction, touchdown, etc.) do not come together properly to ensure a safe landing and roll out. At a controlled airport, the tower may, because of a potentially unsafe situation on the runway, advise the pilot of an airplane on final approach to pull up and go around again

Do not be indecisive about executing a go around. If there is any suspicion that a landing is turning out poorly, start the go around procedure. The sooner you make the decision, the easier and safer the procedure will be. A go around should be viewed as an opportunity to correct what was an unacceptable landing approach and to make a good and safe landing on the next try.

A go around initiated at relatively high altitude is hardly more than a fly through. Initiated at low altitude, it demands attention to proper procedure. Be mentally prepared for the go around on every landing. Complete the landing checklist early. Be sure that rich mixture and fine pitch have been selected. They are needed to achieve full power if a go around is necessary.

Climb at the best angle of climb airspeed until all obstacles have been cleared. Use maximum allowable power until all obstacles have been cleared. Then, assume the best rate of climb airspeed and reduce the power as necessary.

If the go around was initiated because of other traffic on the runway, make a slight turn to parallel the runway when a safe altitude and airspeed have been obtained. Keep the other aircraft in sight until the possibility of a collision no longer exists.

Make a radio call to advise the tower (or on the mandatory frequency [MF] at an uncontrolled airport) of your action at the same time as you are stabilizing the climb at the proper power, speed and trim.

 

CLICK HERE for a more detailed and advanced review of Take-off and Landing performance of airplanes.


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Updated: February 23, 1999