Class B Airspace Authorization and Weather Deterioration
You have received a Part 107 waiver and airspace authorization to fly in Class B airspace near a major airport, with a maximum altitude of 200 feet AGL and a defined operating area. The mission is to inspect a rooftop HVAC unit on a 150-foot tall building located 1.5 miles from the airport. The weather at the time of launch is reported as: wind 12 knots gusting to 20, visibility 5 statute miles, ceiling 2,000 feet overcast, temperature 28°C, dew point 22°C. The sUAS is a quadcopter with a maximum wind resistance of 20 knots. During the preflight, you notice that the battery voltage is slightly lower than usual, but still within acceptable range. While en route, the airport tower announces that the ceiling has dropped to 800 feet and visibility is now 2 statute miles due to incoming weather. Your sUAS is currently at 150 feet AGL, 0.5 miles from the building.
1. What are the regulatory and safety considerations for continuing or aborting the mission given the changing weather?
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Regulatory: Part 107 requires the pilot to maintain visibility of the sUAS at all times (107.31) and to avoid clouds (107.37). The new ceiling of 800 feet and visibility 2 SM still allows flight below 800 feet and within 2 SM, but the pilot must ensure VLOS. However, the sUAS is at 150 feet AGL, which is below the ceiling, but the reduced visibility could impair VLOS. The pilot must also consider the airport's Class B airspace requirements; the authorization may have specific weather minimums. Safety: The wind gusts are near the sUAS's limit, and the temperature-dew point spread (6°C) indicates high humidity, increasing risk of fog or low clouds. The pilot should assess whether the mission can be completed safely. Given the deteriorating weather and the sUAS's proximity to the building, the pilot should consider aborting and returning to launch, as conditions may worsen rapidly.
2. How should the pilot use the DECIDE model to make a decision in this situation?
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DECIDE model: Detect the change: weather deterioration (ceiling drop, visibility reduction). Estimate the impact: reduced visibility may compromise VLOS; wind gusts near limit; potential fog. Choose a course of action: options include continue to building and land, return to launch, or hover and reassess. Identify the best option: returning to launch is safest because conditions are worsening and the mission can be rescheduled. Do it: execute return-to-home, monitor battery and wind. Evaluate: after landing, review the decision and note weather trends for future flights. The pilot should prioritize safety over mission completion, especially with the airport's weather changing rapidly.