TD-25

Question 1

IGE vs. OGE hover airflow vortex pattern

Answer 1

Question 2

Explain why hovering OGE requires more power than hovering IGE.

Answer 2

Induced flow through the rotors increases which requires an increase in rotor pitch angle which increases drag

Question 3

Define Translating Tendency.

Answer 3

During hover flight, counter clockwise rotor rotation creates clockwise fuselage rotation.

To compensate that, left pedal input is required and creates right tail rotor thrust pushing aircraft to the right.

Question 4

To compensate for translating tendency the Helicopter design usually includes one or more of the following:

Answer 4

• Tilt of the mast rotor
• Programmed inputs (AFCS)
• Left cyclic input by the pilot

Question 5

Answer 5