14.86 Hazardous Flight Conditions

14.86.2 Briefly state the conditions leading to, the symptoms of, and the pilot actions to avoid and/or recover from the following:

(a) vortex ring state;

Conditions Leading To:

• Low or zero airspeed
• High rate of descent
• High power setting (high collective)
• Rotor operating in its own downwash/recirculating air

Symptoms:

• High rate of descent despite high power
• Loss of lift / reduced rotor effectiveness
• Vibration / unsteady controls
• Little or no response to increased collective

Avoidance:

• Avoid steep powered descents at low airspeed
• Maintain adequate forward speed
• Monitor rate of descent

Recovery:

• Lower collective (reduce induced flow)
• Apply forward cyclic to gain airspeed (fly out of disturbed air)
• Enter clean airflow