FAA Part 107 Remote Pilot (UAG)Loading and PerformanceHard
A remote pilot reviews a fixed-wing sUAS's performance chart, which lists a maximum demonstrated crosswind component of 15 knots. The current surface wind is reported as 220° at 18 knots, and the planned launch heading is 250°. Should the pilot proceed with launch based on the crosswind limit?
- ANo, because the full 18-knot wind speed exceeds the crosswind limit
- BYes, because the crosswind component is approximately 9 knots, which is within the 15-knot limit
- CThe crosswind component cannot be calculated without knowing the headwind component
- DNo, because the crosswind component is exactly 15 knots, meeting but not staying below the limit
Show answer & explanationAnswer & explanation
Correct answer: B. Yes, because the crosswind component is approximately 9 knots, which is within the 15-knot limit
The angle between wind direction and launch heading is 250° − 220° = 30°. Crosswind component = wind speed × sin(angle) = 18 × sin(30°) = 18 × 0.5 = 9 knots. Since 9 knots is less than the 15-knot maximum demonstrated crosswind component, the pilot may proceed with the launch.
Why the other options are wrong
- A. This confuses total wind speed with the crosswind component, which is only part of the total wind vector.
- C. The crosswind component can be found independently using wind speed and angle difference; headwind is a separate component.
- D. 9 knots, not 15 knots, is the correct crosswind component from this calculation.
Crosswind Component Calculation
The crosswind component is the portion of wind blowing perpendicular to the runway/launch heading, calculated as wind speed × sine of the angle between wind direction and heading.
- Crosswind component = wind speed × sin(angle difference)
- Compare to the manufacturer's maximum demonstrated crosswind component
- Headwind component = wind speed × cos(angle difference)
Memory trick: Sine for shove sideways, cosine for coming at you head-on.