Home › Part 107 Practice Tests › Loading, Performance & Airport Operations Questions › Question 39
What is voltage sag, and when is it most pronounced?
- A.A rise in voltage during gentle flight
- B.A temporary drop in battery voltage under heavy throttle demand
- C.A permanent loss of battery capacity after each flight
Correct answer
B. A temporary drop in battery voltage under heavy throttle demand
Why
When motors demand high current, the battery voltage dips below its resting level. Sag is most pronounced during full-throttle climbs and maneuvers, and it worsens with cold or aging batteries.
Source: FAA-G-8082-22 Ch. 8 · ACS knowledge area: Determining the Performance of an sUAS · From the Loading, Performance & Airport Operations practice bank (PER-039).