Page 19 - Volume 18 Number 6

are set for arrival. Although the precise altitude may vary, let’s use the typical 200 feet Above Ground Level (AGL) point that represents the lowest IFR procedure minimum altitude, except in the most unusual of approaches. As your airplane passes through 200 feet AGL, it should satisfy all of these conditions to safely continue to landing— conditions, when collectively met, I call being “in the slot”:
Airspeed is on target for touchdown. Generally, this will be 1.3 times the stalling speed in the airplane’s current configuration at its current weight. In most Twin and Turbine-type aircraft, this will be a computed or tabulated indicated airspeed from information contained in the Approved Flight Manual (AFM) or Pilot’s Operating Handbook (POH).
The indicated Angle of Attack, if installed, is on target. In some jets the indicated airspeed is secondary to a factory-installed Angle of Attack
(AoA) indicator. If the AFM or POH calls for flying a specific AoA on short final, this becomes a condition for being “in the slot.”
The airplane’s attitude is correct for the type of landing being performed (normal, short field). Pitch attitude, whether visually out the windows or as depicted on an attitude indicator or Attitude/ Heading Reference System (AHRS)- driven display, will be consistent for a given indicated airspeed and/or AoA, at a given center of gravity location and airplane configuration (flap and landing gear position).
Airplane configuration is correct for landing: gear down, flaps set.
Engine power is as expected for the landing. Attitude + Power + Configuration = Performance. In this case, performance results in the proper combination of indicated airspeed and vertical speed at the correct power or thrust setting.
The airplane is on glidepath and aimed to produce a landing in the runway’s touchdown zone. This is usually 1,000 feet from the runway threshold, or one-third of the total usable runway length, whichever is shorter. In the case of a short-field landing (4,000 ft certainly qualifies for a CJ3), the pilot may have to use a touchdown zone closer to the arrival end or the runway, using great care to avoid coming in short or too low over obstacles in the final approach path.
The airplane’s vertical speed is on target to carry the airplane on glide path from the slot location (200 AGL) to the touchdown zone.
If any of those variables is off on short final, you are not “in the slot” and there is increased risk of a runway overrun. Don’t try to salvage the approach. Power up, go around, re-enter the pattern and try for greater precision in another attempt. Or, divert to another runway or airport, if conditions are
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