airspace refresher
Class Bravo airspace requires an explicit ATC clearance before entry - not just radio contact or a squawk code - a distinction that catches VFR pilots off guard more than almost any other rule.
Patterntransponder requirements
The Mode C Veil - The Thirty-Mile Ring Around Class B That Catches Pilots Who Don't Know It's There
The Mode C veil is a 30-nautical-mile transponder requirement around every Class B airport - active even when you never enter Class B airspace.
Pattern