A2 in a Park Beside a Footpath
You hold an A2 CofC and plan to fly a 3.4 kg C2 quadcopter in a public park to practise orbiting a sculpture. The park is bordered on the east by a busy footpath; walkers pass within 12–25 m of your planned orbit centre. The drone has a low-speed mode that limits ground speed to 3 m/s. Wind is 4 m/s from the west, pushing the aircraft toward the path. Your pre-flight site survey identifies a clear emergency landing area 8 m behind you. You have checked the UAS geographical zone map: the park is outside controlled airspace and no NOTAM applies. A family with a dog enters the path and stops to watch.
1. Which Open category subcategory are you operating in, and what horizontal separation must you maintain from the family? Explain how the low-speed mode changes your answer and what you must do before selecting it.
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You are in A2: the aircraft is a C2 (under 4 kg) and you hold the A2 CofC. In A2 the default minimum horizontal distance from uninvolved people is 30 m. The 30 m may be reduced to 5 m only when low-speed mode is active. The family at 12–25 m is inside 30 m, so the default rule is not met.
Reasoning: engaging low-speed mode is not a formality. You must confirm it is actually active and that the aircraft behaves as expected, and you still need a site-specific assessment showing you can keep at least 5 m horizontally at all times. With a 4 m/s westerly wind pushing toward the path, 5 m is too thin a margin: a brief drift or GPS error could breach it. A sensible decision is to move the orbit further west or wait until the path is clear. If you cannot assure the 5 m minimum with a buffer, do not fly that profile.
2. Can you fly directly over the footpath while the family is there? Justify by reference to A2 privileges and what alternative legal options exist.
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No. A2 does not permit overflight of uninvolved people. The privilege is a horizontal separation rule: 30 m normally, reducible to 5 m in low-speed mode. Flying over the family, even at 40 m altitude, would breach that structure because the protection is lateral, not vertical.
Alternatives are limited: you could relocate to an area where A3 conditions apply, but A3 requires staying away from residential, recreational, commercial and industrial areas and keeping 50 m from people, which this park does not satisfy while the fete-style footpath is busy. You cannot simply ‘switch to A1’ unless the aircraft is a C0 or C1 and you meet A1 conditions, and A1 still forbids overflying crowds. The practical answer is to redesign the flight to keep the footpath outside your orbit and outside your drift envelope.
3. During the flight a GPS glitch causes 2 m of uncommanded drift toward the path while the family is 10 m away. Describe your immediate actions and the reasoning.
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Treat separation as the emergency. Immediately stop the orbit, take manual control if you have it, and move the aircraft away from the path, not toward it. Do not spend time diagnosing the GPS glitch while the aircraft is closing on people. If control is uncertain, use the pre-identified clear landing area 8 m behind you rather than triggering a return-to-home that may fly over the footpath.
Reasoning: the 5 m A2 minimum is a hard limit, and 10 m minus 2 m of uncommanded drift leaves no sensible buffer. A controlled landing in the clear area preserves separation; an automatic RTH may climb and track across the path. After landing, inspect the event, record it, and do not relaunch until the cause is understood and the site is re-assessed.