Performance Class B (CS-23): Take-off and Landing Theory

Take-Off Performance

For Class B, take-off calculations are simpler but include specific safety factors.

Take-Off Distance Required (TODR)

The distance to accelerate from a standing start to a screen height of 50 ft above the take-off surface.

• All Engines Operating (AEO): Assuming all engines are working normally.
• Factor: The Gross TODR (from the manual) must be multiplied by factors:
  • $\times 1.25$ required for commercial operations (Public Transport).
  • $\times 1.15$ or $1.05$ for grass/wet runways.
  • Adjustments for slope and wind.

Rejected Take-Off

Unlike Class A, there is no strict regulation for "Accelerate-Stop Distance Required" (ASDR) for single-engine Class B aircraft in the same way. The pilot determines a "go/no-go" point based on runway length and experience.

Obstacle Clearance

The take-off flight path must clear all obstacles by a vertical margin of 50 ft.

Landing Performance

Landing Distance Required (LDR)

The distance from a screen height of 50 ft above the landing threshold to a complete stop.

Landing Distance Available (LDA)

For commercial operations, the LDR must not exceed a percentage of the LDA:

• Standard Factor: LDR must be $\le 70\%$ of LDA (or LDA $\ge 1.43 \times$ LDR).
• Wet Factor: If the runway is wet, the LDR calculation must effectively be increased by $\times 1.15$.

Unpaved Runways

Class B aircraft frequently operate from grass or gravel strips.

• Grass (Dry): $\times 1.2$ factor for take-off distance.
• Grass (Wet): $\times 1.3$ factor (or soft ground).