Class C Entry After 'Stand By' and a Transponder Failure
A private pilot of a gyroplane with a serviceable Mode C transponder is flying at 2,500 ft MSL, 8 nm southwest of a Class C primary airport. The Class C is configured with an inner area from the surface to 4,000 ft MSL within 5 nm and an outer area from 1,200 to 4,000 ft MSL within 10 nm. The pilot calls approach control: 'Gyroplane 12345, 8 miles southwest at 2,500, request Class C transition.' The controller replies: 'Gyroplane 12345, stand by.' The pilot waits about 20 seconds, hears no further call, and continues into the outer area. Two minutes later the transponder fails, showing only primary targets on the controller's scope, and the pilot continues to the destination airport inside the Class C inner area. The pilot has a handheld radio as backup and the airport is 6 nm ahead.
1. Was the entry into the Class C outer area legal? Explain what constitutes authorization.
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No. Class C requires established two-way radio communication and a Mode C transponder. 'Stand by' is not an authorization; ATC must use the aircraft's callsign and clear it into the area or instruct it to remain outside. The pilot entered the outer ring without authorization. The outer ring is still Class C airspace from 1,200 to 4,000 ft MSL, so the communication and transponder requirements apply there as well.
The pilot should have remained clear, repeated the request, or circled outside. Twenty seconds of silence does not convert a 'stand by' into a clearance. Even if the controller would have approved later, the entry was a violation.
2. What should the pilot do when the Mode C transponder fails inside Class C?
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Notify ATC immediately, state that the transponder has failed, and request either authorization to continue or vectors out of Class C. The regulations allow ATC to authorize continuation with an inoperative transponder, but the pilot cannot assume that authorization. If ATC cannot authorize, exit the airspace and land as soon as practicable.
The handheld radio is a backup for communication, but it does not satisfy the installed-radio or transponder requirements. Continuing silently into the inner area is not acceptable. If the failure occurs while already inside, advise ATC and follow their instructions; do not simply press on to the destination.
3. If the radio also fails, what should the pilot do, and what was the original error?
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Squawk 7600, remain VFR, exit Class C, and watch for light-gun signals. Radio failure means the pilot cannot meet the requirement to maintain two-way communication in Class C. Land at the nearest suitable airport and call ATC by phone. If already inside, continue only if that is the safest option and ATC has acknowledged; otherwise divert.
The original error was treating 'stand by' as permission. The correct action was to stay outside the airspace and ask again. The transponder failure compounded the problem, but the pilot should have been outside Class C in the first place.