A remote pilot is conducting a linear mapping flight along a 3-mile ridgeline at 400 feet AGL. Two miles into the flight, the automated mission reports ground speed has dropped from 22 mph to 8 mph and battery consumption has risen sharply. The forecast surface wind was 12 knots. What is the most accurate interpretation and correct action?
Why →
Surface winds reported at a station are rarely the same as winds at 400 feet AGL, particularly along ridgelines where terrain accelerates flow. Ground speed reduction combined with higher battery draw is a classic signature of a strong headwind at altitude. The correct response is to abort the leg, reassess winds aloft, and decide whether a revised altitude or route makes the mission feasible.The trap →
Choices B and C treat an aerodynamic performance symptom as a mechanical failure. A pilot who does not understand wind gradient will replace a perfectly good battery or waste time on maintenance diagnostics when the actual issue is an operating environment the pre-flight briefing did not capture.SOURCE → FAA Remote Pilot Study Guide FAA-G-8082-22, Weather and Terrain; 14 CFR § 107.49CHECKED APR 21ACS III.B.K1HARD