Incident Details
On an IFR departure from Runway 18 at Merrill C Meigs Airport, a Piper PA-31T (registration N484SC) and a Swearingen SA226T (registration N600TA) on an IFR arrival converged approximately 3 miles south of the airport. The crew of N484SC sighted N600TA and executed a turn to maintain separation. The passing distance was estimated to be about 2,000 feet.
Investigation Findings
An investigation revealed that as N600TA was arriving, the south satellite sector #1 controller at Chicago O'Hare TRACON had cleared the crew to descend and maintain 2,000 feet. When N600TA advised that Meigs was in sight, the sector #1 controller cleared them for a visual approach and instructed them to contact Meigs Tower.
At about that time, the south satellite sector #3 controller at TRACON was in contact with Meigs Tower to provide information about N600TA concerning another matter. The sector #3 controller released N484SC for a south-bound departure. When providing the release, the sector #3 controller was unaware that N600TA had been cleared for a visual approach.
When N600TA contacted Meigs Tower, the tower controller thought it was on a VFR arrival. Visibility was restricted by fog and haze at the time.