According to AC 107-2A's risk-assessment guidance, what night-operation hazard is associated with unlit towers and buildings near the area of operation?

Why: AC 107-2A Appendix A (p. A-5) states that night-operation hazards "include night vision adaptation when unlit towers and buildings are present in the area of operation."

• Invents a waiver requirement; the AC's checklist flags unlit structures as a hazard to assess and mitigate, not as a trigger for a mandatory Certificate of Waiver.
• Invents an altitude exemption; nothing in Part 107 or the AC ties a structure's lighting status to the 400-foot AGL limit — the hazard identified is visual detection at night, not altitude.