AA.I.B.K2bFAA-S-ACS-11A · Nov 2023Knowledge
b. Takeoff performance [e.g., balance field length and Velocity, Minimum Control (groun...
How to determine the following, as applicable to the class sought: b. Takeoff performance [e.g., balance field length and Velocity, Minimum Control (ground) (VMCG)]
Bottom line
Takeoff performance for transport category operations includes minimum control speed with the critical engine inoperative during the takeoff roll, known as VMCG. Air carrier takeoff performance requirements include balanced field length, accelerate-go, and accelerate-stop calculations. Takeoff performance calculations must account for the effect of variable flap settings on runway distance used and second segment climb performance.
Key numbers
| Number | What it means |
|---|---|
| 1.2% at end of takeoff path, two critical engines inoperative (14 CFR 91.611(c)(4)) | Ferry climb gradient |
| up to 30% lift loss, 40% drag increase (sandpaper-like ice/frost/snow on wing) | Contamination penalty |
FAA references
- AC 61-138, para. 14.3.8.2 — AC No: 61-138A
- 14 CFR 91.611 (Authorization for ferry flight with one engine inoperative.) — eCFR current as of 2026-03-05
- AC 20-117, para. 4a — AC No: 20-117
- AC 91-74, para. 7-1 — AC No: 91-74A
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