Short-field takeoff procedures are utilized when an airplane must be operated from an area with either a short runway or the available takeoff area is restricted by obstructions. These operations require accurate preflight planning and precise aircraft control to obtain the maximum performance from the airplane.
“Power Set”:
“T&P’s in the Green”: Engine temperatures and pressures should be in their normal ranges.
“Airspeed Alive”: Check the airspeed indicator for proper operation. Indications typically begin as the airplane accelerates through 20–30 knots.
The most critical conditions of takeoff performance are combinations of:
Rules of thumb:
Rules of thumb:
An increase in density altitude:
Setup:
Takeoff Roll:
Liftoff:
Maximum Performance Climb:
Short-field landing procedures are utilized when an airplane must be operated into an area with either a short runway or the available takeoff area is restricted by obstructions. These operations require pilots to fly a stabilized approach that clears obstacles, results in little or no floating, and permits the airplane to stop in the shortest possible distance.
A stabilized approach is one in which the pilot establishes and maintains a constant-angle glide path toward a predetermined point on the landing runway. It is based on the pilot’s judgment of certain visual clues and depends on maintaining a constant final descent airspeed and configuration.
A stabilized approach provides:
An airplane descending on final approach at a constant rate and airspeed travels in a straight line towards a spot on the ground ahead, commonly called the aiming point.
To the pilot, the aiming point appears to be stationary. It does not appear to move up or down on the windscreen. Objects in front of and beyond the aiming point appear to move as the distance is closed, and they appear to move in opposite directions.
If the airplane maintains a constant glide path without flaring, it will strike the ground at the aiming point. However, the airplane will not touch down at the aiming point because some float does occurs.
Taking into account float during round out, the pilot can predict the touchdown point within a few feet. The actual location of the touchdown should be approximately 1,000′ down the runway and within the first third of the runway.
Airspeed and altitude are controlled in flight through a combination of pitch and power (thrust) adjustments. Through experience, pilots learn to lead with the control that provides the most responsiveness so that their flying becomes more precise.
All phases of flight can be divided into two basic power conditions: fixed-power and adjustable-power. An adjustable-power condition exits when power is both variable and available. In all other situations, power remains constant (fixed) either by choice or due to an engine failure.
Most phases of flight occur with a fixed-power setting. With power fixed, the pitch control manages altitude, airspeed, or vertical speed (climb or descent rate), as appropriate.
Examples of fixed-power conditions:
Although small, occasional power adjustments may be needed in these phases of flight, power is still considered “fixed.”
The pitch control is used to adjust the flight parameter that demands the quickest response and the most precision. The airplane responds quickly to pitch control inputs because the angle of attack (AOA) on the elevator (or stabilator) changes instantly. Adjusting power generally takes longer to have a noticeable effect, especially with turbine engines, which take several seconds to spool up.
Examples of adjustable-power conditions:
Some situations can be corrected with a trade-off (exchanging altitude for airspeed and vice versa). For example, if the airplane is both high and slow, the pilot can leave the power alone and pitch down.
The following table describes the effect of moving a single control (pitch or power) during an approach to a landing.
Control Input | Energy Effect | The Airplane Moves |
---|---|---|
Increase power | More total energy | Higher and faster |
Decrease power | Less total energy | Lower and slower |
Increase pitch | Same total energy; Speed is traded for height | Higher but slower |
Decrease pitch | Same total energy; Height is traded for speed | Lower but faster |
Key Takeaways:
Small, reciprocating engines react quickly to power inputs, so there is little difference in the response time of the pitch and power controls. This opens up room for a debate over which control should be used to manage airspeed, especially during a visual approach and landing.
Considerations for choosing a technique:
The most critical conditions of landing performance are combinations of:
Rules of thumb:
Aerodynamic drag can be used in the early stages of the landing roll. Unlike wheel brakes and tires, which suffer from continuous hard use, aerodynamic drag is free and does not wear out with use.
The use of aerodynamic drag is most beneficial for decelerating to 60% to 70% of the touchdown speed. At slower speeds, aerodynamic drag becomes less effective. Wheel braking must be increased to produce continued deceleration.
The minimum landing distance varies in direct proportion to the gross weight. An increase in gross weight requires a faster approach speed and requires more effort to decelerate to a stop after landing.
A 10% increase in gross weight causes:
An increase in density altitude increases the landing speed. The aircraft at altitude lands at the same indicated airspeed (IAS) as at sea level, but the true airspeed (TAS) is greater because of the reduced density.
Because a given IAS corresponds to a higher TAS at higher density altitudes, pilots are sometimes “tricked” by visual cues and fly slower than they should.
The approximate increase in landing distance with altitude is approximately 3.5% for each 1,000′ of altitude. At 5,000′, the required landing distance is 16% greater than at sea level.
Excessive speed upon touchdown:
The stopping distance of an object (assuming the same braking force) is directly proportional to its kinetic energy. If the kinetic energy quadruples, the stopping distance also quadruples.
Rules of thumb:
Sometimes variations in the normal approach speed should be made to compensate for changes in weight and gusty wind conditions.
Normal Approach Speed: In the absence of the manufacturer’s recommended approach airspeed, a speed equal to 1.3 VSO should be used.
Example Calculation
58 VS0 × 1.3 = 75 KIAS
Variations in Weight: Manufacturers typically publish the approach speed at the airplane’s maximum gross weight. The approach speed for a lower operating weight can be approximated with the following formula; however, the manufacturer’s published speeds and recommendations should be followed.
VREF1 = VREF2 × √(Current Weight ÷ Maximum Gross Weight)
Example Calculation
2,000 Actual Weight ÷ 2,500 Gross Weight = .80
√.80 = .894
75 KIAS X .894 = 67 KIAS
Wind Gust Factor: Slightly higher than normal airspeeds provide more positive control during strong horizontal wind gusts. One procedure is to use the normal approach speed plus one-half of the wind gust factor.
Example Calculation
"Wind 180° at 10 knots gusting to 20 knots."
½ of the 10 knot gust factor = 5 KIAS
67 + 5 = 72 KIAS
Setup:
Approach:
Round Out (Flare):
Touchdown:
After-Landing Roll:
Obstacle Clearance Speed:
Climb Speed:
Approach Speed:
Touchdown Point:
A stabilized approach is characterized by a constant-angle, constant-rate of descent approach profile ending near the touchdown point, where the landing maneuver begins. Slight and infrequent adjustments are all that are needed to maintain a stabilized approach.
C-FLAPS
The recommended minimum stabilization heights are:
The objective is to stabilize the aircraft before reaching the predetermined minimum stabilization height. If the aircraft is not stabilized at the minimum stabilization height or becomes unstabilized below it, a go-around should be initiated.
Too Slow | Desired Speed | Too Fast | |
---|---|---|---|
High | Exchange energy by pushing the pitch control forward to accelerate and descend simultaneously. Maintain the power setting. | Reduce the power setting to reduce total energy. Use the pitch control to maintain the correct airspeed and descend. | Reduce the power setting significantly to decrease total energy. Pull back on the pitch control gradually to decelerate to the correct airspeed and then descend. |
Too Slow | Desired Speed | Too Fast | |
---|---|---|---|
Desired Altitude or Glide Path | Increase the power setting to gain total energy by accelerating. Use the pitch control to maintain the desired altitude. | DESIRED ENERGY STATE Maintain the power setting and pitch attitude. Trim to relieve control pressures. |
Reduce the power setting to decelerate. Use the pitch control to maintain the desired altitude. |
Too Slow | Desired Speed | Too Fast | |
---|---|---|---|
Low | Increase the power setting significantly to gain total energy. Push the pitch control forward gradually to accelerate to the correct airspeed and then climb. | Increase the power setting to gain altitude and pull back on the pitch control to maintain the correct airspeed. | Exchange energy by pulling back on the pitch control to climb and decelerate simultaneously. Maintain the power setting. |