PA.IV.K.K1FAA-S-ACS-6C · Nov 2023Knowledge
Effects of atmospheric conditions, including wind, on takeoff and climb performance.
Effects of atmospheric conditions, including wind, on takeoff and climb performance.
Bottom line
High, hot, and humid conditions reduce engine power and propeller efficiency, and the seaplane must also attain a higher water speed in order to generate the lift required for takeoff.
Key numbers
| Number | What it means |
|---|---|
| 1,000 feet for takeoff at sea level under standard atmospheric conditions (average small airplane) | Sea level run |
| approximately 2,000 feet takeoff run at an operational altitude of 5,000 feet | At 5,000 feet |
| do not fly a light aircraft when winds aloft at the proposed altitude exceed 35 miles per hour | Winds aloft limit |
| 1,500 to 2,000 feet per minute on the leeward side of mountain passes | Leeward downdrafts |
FAA references
- AIM 7-6-7 (Mountain Flying) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- SEA ch. 4 (p. 4-12) — FAA-H-8083-23
- PHAK ch. 5 (p. 5-12) — FAA-H-8083-25C (2023)
- RMH ch. 3 (p. 3-7) — FAA-H-8083-2A
- PHAK ch. 5 (p. 5-42) — FAA-H-8083-25C (2023)
- RMH ch. 3 (p. 3-6) — FAA-H-8083-2A
- AFH ch. 9 (p. 9-12) — FAA-H-8083-3C
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