Cessna Single Piston Undifferentiated or Other Model
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 2
Human-Machine Interface; Troubleshooting; Situational Awareness
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Airspace Structure; Chart Or Publication; Aircraft; Human Factors
I was working the CMH east side airspace combined. Our class C airspace extends from the surface to 4;800 feet in the inner ring and from 2;500 feet to 4;800 feet in the outer ring. I noticed a VFR Mode C intruder entering the north east side of our outer ring at 2;600 feet. Due to altimeter variations this sometimes happens with the aircraft actually being below the 2;500 foot floor; so I did not initially consider him an airspace violator.The aircraft proceeded to climb to 4;000 feet; enter the inner core of the Class C airspace and proceed west/southwest bound across our departure corridor. Once the aircraft left 2;800 feet I tagged the aircraft as a 'BUSTR' to track; informed the supervisor; and informed the Tower. With the addition of ADSB if an aircraft is tagged as something other than its registered call sign; you are able to press 'multi-function D' then press enter on the target to view its ADSB information and its registered call sign. I was able to determine the transponder belonged to a Cessna.This aircraft had busted our Class C airspace the week before. I was able to view the ADSB information then as well. Last week the aircraft landed at an airport; but we were unable to reach anyone on the ground to request the pilot to contact us. The previous airspace violation was sent to the region; and returned stating they were unable to do anything since we did not actually speak to the pilot. It could have been anyone flying the aircraft; so they were unable to verify the owner was the one flying. This time the aircraft landed at [a different] airport. The CIC was able to contact a person at the FBO. The FBO worker informed the pilot when he entered that we were requesting to speak with him and gave him the TRACON phone number. The pilot did not call back.Now that we are able to determine aircraft call signs based on ADSB information there should be some avenue to discuss these kind of events with aircraft owners when this information is known. When an aircraft has busted controlled airspace twice in a week; it is a safety issue that needs to be addressed. This aircraft spent 12 minutes in Class C airspace and cut across a departure corridor. We know the aircraft registration; but are unable to educate the pilot due to his lack of compliance with a request to contact ATC.
A TRACON Controller reported an aircraft violated Class C airspace.