VFR Weather Minimums

The core idea is that busier or higher airspace demands more room from clouds. In Class B, where ATC separates everyone, you only need 3 statute miles of visibility and to remain clear of clouds. In Class C, D, and E below 10,000 feet MSL you need 3 statute miles and the "3-152" cloud clearances: 500 feet below, 1,000 feet above, and 2,000 feet horizontally from clouds. Class G is the exception with lower requirements close to the ground during the day — 1 statute mile and clear of clouds below 1,200 feet AGL — because traffic is slower and lower there. The test wants the FULL Class G grid: below 1,200 AGL it is 1 SM/clear of clouds by day, and 3 SM with 3-152 clearances at night (except that an airplane in an airport traffic pattern within one-half mile of the runway may operate at night with 1 SM and clear of clouds). From 1,200 AGL up to but below 10,000 MSL, Class G requires 1 SM day / 3 SM night, both with 3-152 clearances. At or above 10,000 feet MSL (and more than 1,200 AGL), BOTH Class G and Class E require 5 statute miles with 1,000 below, 1,000 above, and 1 statute MILE horizontal — the faster traffic up high needs more room. Always confirm the exact values in the current regulation (14 CFR 91.155). When the weather at a controlled-airport surface area drops below these basic minimums, a pilot can ask ATC for a Special VFR (SVFR) clearance: with it you may operate remaining clear of clouds with at least 1 statute mile of visibility. SVFR must be requested from and granted by ATC, is not available where the airport is marked "No SVFR," and at night requires the pilot to be instrument rated and the aircraft to be instrument equipped.