Take-off & landing distance
Chart distances assume paved, level, smooth, dry runway at max gross weight (PHAK ch.11). Book number: AFM/POH chart. Corrections compound: multiply, never add.
Altitude, heat, humidity (TP 1102):
- Each thins air, lengthens roll.
- Cold, dry air is densest: best performance.
- Worst take-off and climb: high temperature, high airport elevation, low pressure, high humidity together (high density altitude).
Wind (TP 1102):
- Headwind: shortens take-off run and landing roll; lowers groundspeed at liftoff.
- Tailwind: lengthens roll.
- Only headwind component counts.
- Wind 70-90° off runway: plan landing roll as for no wind.
- Light, shifting winds: plan as no wind.
Weight (PHAK ch.5; TP 1102 Approach and Landing: Gross Weight):
- Heavier gross weight: lengthens take-off run, shallows climb, raises touchdown speed, lengthens landing roll.
- Lighter than max gross: shortens roll.
- Even a minor overload may stop obstacle clearance that is normally no problem (PHAK ch.5).
Surface:
- Any surface not hard and smooth lengthens ground roll: grass, mud, gravel, snow, standing water (PHAK ch.11).
- Contaminated take-off (no CRFI correction, AFM increase, reject point):
contaminated-takeoff-reject-point.
Landing area, snow and ice (TP 1102):
- A couple of inches of snow can put aircraft on nose or back.
- Ice or standing water can mean reduced or no braking.
Unapproved estimates:
- AFM take-off chart exists: use it.
- Koch chart is fallback: reads increase in take-off distance from pressure altitude and temperature only.
- Gives representative values only; may be conservative for turbocharged engines (TP 1102).
- Example: 6,000 ft pressure altitude at 38°C needs 220 percent more distance than sea level ISA.
Trainer model:
Real charts are graphs; trainer fixes one model for hand computation.
| Correction | Factor |
|---|---|
| Pressure altitude | 1 + 0.10 × PA/1000 |
Temperature (ISA = 15 - 2 × PA/1000 °C) |
1 + 0.01 × (OAT - ISA) |
| Headwind | 1 - 0.01 × kt |
| Tailwind | 1 + 0.05 × kt |
| Weight | 1 - 0.01 × (100 - weight%) |
| CRFI 0.50 / 0.40 / 0.30 / 0.25 / 0.20 (landing) | ×1.8 / ×2.0 / ×2.2 / ×2.35 / ×2.5 |
distance = base × PA × temp × wind × weight × CRFI
Factor sources:
- Wind rates rounded from PHAK Fig 11-24 sample take-off table (rule of thumb for that one aircraft, not universal ratio):
- Headwind: -10% per 9 kt.
- Tailwind: +10% per 2 kt (tailwind up to 10 kt).
- CRFI factors = recommended landing distance divided by dry unfactored distance in Table 1.3 (about 1.8 to 2.5, stable across runway lengths).
TP 1102 landing example (60 kt):
| Wind | Landing roll |
|---|---|
| 20 kt headwind | about 800 ft |
| 20 kt tailwind | about 1,600 ft (moderate to heavy braking past 800 ft) |
- Roll doubles.
TP 1102 weight example:
- Pilot and half fuel: rolls about 500 ft after touchdown.
- Full fuel and passenger (260 lb more): rolls extra 138 ft.
Most light aircraft need more room to take off than to land: never land where you could not take off again (ASL 3/2025).
Trap: tailwind lengthens roll more than equal headwind shortens it: wind of 10% of lift-off speed cuts take-off run about 19% as headwind, adds about 21% as tailwind (PHAK ch.11, Effect of Wind); sample table steeper (10% per 2 kt vs 10% per 9 kt), so even light tailwind hurts.
References
- Aircraft POH/AFM (performance section)
- TP 1102 (Flight Training Manual: take-off performance, Koch chart, landing run)
- TC AIM AIR 1.6.7 (CRFI application: Table 1.3 landing distances)
- PHAK ch.5 (Effect of Weight on Flight Performance), ch.11 (Runway Surface and Gradient, Fig 11-24 notes)