Roof survey beside a market queue
An A2 certificate holder is commissioned to photograph a two-storey roof using a 3.6 kg C2 quadcopter. The launch point is a narrow service yard. A queue of about 25 uninvolved shoppers stands along the pavement 9 m horizontally from the planned hover point; the drone will be 18 m above roof level, so slant range is over 20 m. The pilot selects low-speed mode, which limits ground speed to 2.8 m/s, and checks that GPS lock and obstacle sensing are normal. Weather: surface wind 4 m/s, gusts 11 m/s, gust spread increasing. The pilot plans a 6-minute flight and says the 30 m rule is satisfied because the aircraft is high and the queue is not directly under it. A second person occasionally steps into the yard.
1. Evaluate the planned 9 m horizontal separation. Does low-speed mode make it compliant, and what does the gusty wind change?
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The baseline A2 rule is 30 m horizontal distance from uninvolved people. That distance may be reduced to 5 m only when low-speed mode is active and the pilot judges the risk acceptable. Height and slant range do not substitute for horizontal separation.
At 9 m, the flight is inside the 30 m baseline but outside the 5 m floor, so the only possible basis is the reduced-distance regime. Low-speed mode at 2.8 m/s is selected, which fits the C2 concept, but the gusty wind changes the judgement: low-speed mode limits commanded ground speed, not wind-induced drift. Gusts of 11 m/s with increasing spread make it harder to hold a stable track near a queue only 9 m away. A second person can also enter the yard and shrink separation without warning. Because A2 still forbids overflight of uninvolved people, drift could also put the queue under the aircraft. The flight is therefore not compliant as planned; reposition to keep 30 m, cordon the yard, or postpone.
2. Suppose low-speed mode disengages in flight while the drone is 10 m from the queue. What should the remote pilot do?
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Once low-speed mode is no longer active, the reduced 5 m distance no longer applies. The minimum becomes 30 m horizontal, and the aircraft is at about 10 m. Continuing the inspection would breach the A2 distance rule and could lead to overflight if the queue moves or the aircraft drifts.
The pilot should stop the task and move the aircraft away from the queue rather than simply climbing, because climbing does not increase horizontal separation. If the aircraft cannot be moved safely away, land in a clear part of the yard away from people. Do not continue the photographic pass and do not rely on the earlier low-speed selection; the condition must be active when the separation is relied on.