Narrative:

I requested clearance from tower 'depart at 2;000 feet; with the tower; negative flight following; on assigned code.' I received a clearance of 'maintain at or below 2;500 feet; with the tower; on assigned code' (or similar words). We departed and climbed to 2;500 MSL on tower frequency. At 10 miles; the tower frequency changed us. As we had not requested VFR flight following; I did not contact departure. Our chief pilot received a phone call after the flight questioning why we had flown into class C airspace without contacting departure (class C beyond 10 miles starts at 2;100 feet MSL). We typically receive a clearance at 2;000 feet MSL or below. I did not catch that our clearance to 2;500 feet took us into class C airspace which would mean that we needed to have contact with departure control.

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Original NASA ASRS Text

Title: The Captain of a Sikorsky S-76 reported that they unknowingly flew into a Class 'C' airspace without clearance.

Narrative: I requested clearance from Tower 'depart at 2;000 feet; with the Tower; negative flight following; on assigned code.' I received a clearance of 'maintain at or below 2;500 feet; with the Tower; on assigned code' (or similar words). We departed and climbed to 2;500 MSL on Tower frequency. At 10 miles; the Tower frequency changed us. As we had not requested VFR flight following; I did not contact Departure. Our Chief Pilot received a phone call after the flight questioning why we had flown into Class C airspace without contacting departure (Class C beyond 10 miles starts at 2;100 feet MSL). We typically receive a clearance at 2;000 feet MSL or below. I did not catch that our clearance to 2;500 feet took us into Class C airspace which would mean that we needed to have contact with Departure Control.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.