FlyCurrentFLYCURRENT
CA.IV.K.K2FAA-S-ACS-7B · Nov 2023Knowledge

Best angle of climb speed (VX) and best rate of climb speed (VY).

ACS element text (the applicant demonstrates understanding of)

Best angle of climb speed (VX) and best rate of climb speed (VY).

Bottom line

VX is used during a short-field takeoff to clear an obstacle. Best rate-of-climb speed (VY) is the airspeed that provides the most altitude gain in a given period of time.

Key numbers

Key numbers for Best angle of climb speed (VX) and best rate of climb speed (VY).
NumberWhat it means
greatest altitude in a given distanceVX definition
most altitude in a given timeVY definition

FAA references

  1. PHAK ch. 8 (p. 8-10) — FAA-H-8083-25C (2023)
  2. SEA ch. 4 (p. 4-12) — FAA-H-8083-23
  3. AFH ch. 16 (p. 16-17) — FAA-H-8083-3C
  4. AIM 10-1-2 (Helicopter Instrument Approaches) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
Members lesson

Build understanding you can use

Unlock the full lesson and continue studying this element.

  • Full teaching sections: What it is; Key points; How it is done
  • Check your understanding with answers you can reveal
  • Common mistakes paired with the FAA facts that correct them
View membership options