FAA Aerodynamics of sUAS 3

Question 1

How does wind shear affect sUAS flight operations?

Accepted Answer

A sudden change in wind speed or direction can cause rapid attitude changes and potential loss of control

Answer

Abrupt wind shear can instantly change the relative wind acting on all rotors simultaneously, causing attitude excursions that the flight controller may not recover from quickly enough.

Question 2

How does operating in hot, humid summer conditions affect sUAS endurance compared to cool, dry conditions?

Accepted Answer

Hot, humid conditions reduce endurance because lower air density requires higher RPMs for the same lift

Answer

High temperature and humidity reduce air density (increase density altitude), requiring motors to spin faster and consume more power per minute, shortening total flight time.

Question 3

What is the primary aerodynamic concern when operating an sUAS near large buildings or other tall structures?

Accepted Answer

Mechanical turbulence and unpredictable wind gusts caused by airflow disruption around the structures

Answer

Buildings disrupt smooth laminar airflow and create mechanical turbulence, eddies, and unpredictable gusts on the leeward side that can cause sudden and severe attitude excursions.

Question 4

How can a strong tailwind affect an sUAS during high-speed forward flight?

Accepted Answer

A strong tailwind reduces relative airspeed over the rotors, decreasing control effectiveness and lift efficiency

Answer

Rotor lift and control authority depend on relative airspeed — a strong tailwind reduces the relative wind over the rotors, degrading lift efficiency and pitch/roll control response.

Question 5

What phenomenon commonly occurs when an sUAS performs a rapid deceleration (quick stop) from high-speed forward flight?

Accepted Answer

The aircraft pitches nose-high and may experience a momentary altitude loss before stabilizing

Answer

During a quick-stop, inertia carries the aircraft forward while the rotor disc tilts rearward to brake — the nose pitches up, the vertical lift component decreases, and altitude drops momentarily.

FAA - Part 107 Test Practice Test

FAA - Part 107 Test Practice Test

FAA Aerodynamics of sUAS 3