AI.XIII.C.K5bFAA-S-ACS-25 · Nov 2023Knowledge
b. Wing flaps extended
Effects on performance of various configurations including: b. Wing flaps extended
Bottom line
When extended, flaps move simultaneously downward to increase the lifting force of the wing for takeoffs and landings. VFE is the highest speed permissible with the wing flaps in a prescribed extended position, because of the air loads imposed on the structure of the flaps.
Key numbers
| Number | What it means |
|---|---|
| VFE — highest speed permissible with flaps in a prescribed extended position | Flap speed |
| Do not pass VNE, VLE, or VFE, as applicable | Emergency descent |
FAA references
- PHAK ch. 3 (p. 3-5) — FAA-H-8083-25C (2023)
- PHAK ch. 11 (p. 11-19) — FAA-H-8083-25C (2023)
- AFH ch. 18 (p. 18-9) — FAA-H-8083-3C
- AFH ch. 12, Operational Procedures (pp. 12-4–12-5) — FAA-H-8083-3C
- PHAK ch. 5 (p. 5-50) — FAA-H-8083-25C (2023)
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