Airman Certification Standards
ACS PH.VIII.I
Ground Resonance
This reproduces published FAA reference text for study. It does not replace the current official FAA publication or regulation.
Knowledge
K1
Exhibits knowledge of the elements related to ground resonance by describing:
K1a
a. Conditions that contribute to ground resonance
K1b
b. Preventive flight technique during takeoffs and landings
K1c
c. Landing surface
K2
Inspection of items that may contribute to ground resonance.
K3
Corrective actions during low and normal rotor rpm speeds. 47
Risk Management
R1
Factors that may contribute to the onset of ground resonance.
R2
Recognition of the onset of ground resonance.
R3
Recovery procedure selection.
Skill
S1
[Intentionally left blank].
Retrieved from ecfr.gov on July 17, 2026.