Factors Affecting Take-off and Landing Performance

Introduction

This section addresses the effect of various environmental and operational factors on the take-off, landing, and take-off climb performance of an aircraft. Understanding these effects is essential for pilots to make informed decisions and ensure safe operation under varying conditions.

Runway Slope and Surface

Effects on Performance

1. Runway Slope:

   • Take-off and Landing Distance: An uphill slope increases the take-off distance and reduces landing distance by approximately 5% per 1% slope (FSF ALAR Briefing Note 8.5 - Flight Safety Foundation).

2. Wet and Slushy Runways:

   • Take-off: Increased drag from water or slush can extend take-off distance by 30-70% (Water/slush on the runway - SKYbrary).
   • Landing: Reduced braking efficiency on wet or slushy runways increases the landing distance (FSF ALAR Briefing Note 8.5 - Flight Safety Foundation).

Frost on the Aircraft

Effects on Performance

• Lift and Drag:

  • Frost can decrease maximum lift by up to 30% and increase drag by up to 40%, significantly affecting take-off and climb performance (6 Reasons Why Frost on Your Wings is Dangerous - Boldmethod).

• Take-off and Climb:

  • Reduced lift and increased drag impair climb performance, requiring higher airspeeds and increasing the risk of asymmetrical stalls.

Density Altitude (Non-standard Conditions)

Effects on Performance

• Take-off and Landing:

  • High density altitudes reduce engine power and lift, increasing needed take-off and landing distances (Aircraft Performance - FAA).

• Climb Performance:

  • A higher density altitude diminishes climb rates due to decreased thrust and aerodynamic performance (Density Altitude - AOPA).

Air Temperature

Effects on Performance

• Air Density:
  • Higher temperatures decrease air density, necessitating longer take-off rolls, higher approach speeds, and potentially reducing maximum take-off weight (How Temperature Affects Aircraft Performance - Simple Flying).

Airfield Elevation

Effects on Performance

• Take-off and Landing:
  • Higher elevation means lower air density, increasing required take-off and landing distances and impacting both lift and engine performance (Chapter 6 - Airplane Flying Handbook).

Strength of Headwind/Tailwind Component

Effects on Performance

1. Headwind:

   • Take-off and Landing: Reduces runway distance required as aircraft can achieve lift-off at lower ground speeds (Headwind Operations - SKYbrary).

2. Tailwind:

   • Take-off and Landing: Increases runway length needed, potentially requiring reduced weight (Tailwind Operations - SKYbrary).

Ground Effect and Windshear

Effects on Performance

1. Ground Effect:

   • Increases lift and alters control feel near the ground during take-off and landing, necessitating careful handling (20. Flight Studies of Ground Effects on Airplanes - NASA).

2. Windshear:

   • Can rapidly change airspeed and altitude unexpectedly, critical in approach, and requires readiness to respond (Windshear Awareness - SKYbrary).

QNH (Mean Sea Level Pressure)

Effects on Performance

• Altitude Measurement:
  • Influences pressure altitude calculations needed for performance assessments, impacting safety margins during take-off and landing (Altimeter Setting Procedures - SKYbrary).

Conclusion

Various factors such as runway conditions, environmental parameters, and specific aircraft characteristics can significantly impact the take-off, landing, and climb performance of an aircraft. Understanding and anticipating these effects allows pilots to adjust operations and enhance safety during critical flight phases.