Under 14 CFR § 107.23(a), a small unmanned aircraft system may not be operated —

Why: 14 CFR § 107.23(a) prohibits operating a small UAS "in a careless or reckless manner so as to endanger the life or property of another."

• Confuses the general hazardous-operation prohibition with the separate altitude operating limitation in § 107.51(b), which caps altitude at 400 feet AGL but allows an exception near structures.
• Treats visual observer use as always mandatory, but § 107.33's requirements only apply if a visual observer is used; § 107.23 itself says nothing about requiring one.