EMB ERJ 135 ER/LR
Communication Breakdown
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance
Procedure; Human Factors
I was working an aircraft on the localizer while departures were approved using opposite direction; same runway. The weather was low VFR but was improving steadily. An earlier departure was clear of the course of the arrival while the arrival was still 15 NM from the airport. The subject departure appeared on the RADAR scope when the arrival was about 8 NM from the airport; appearing then as opposite direction; the pilot had not yet started the Local-assigned turn. I think that since the weather had been lower and even included thunderstorms adjacent to the airport on the other side of the field; it did not occur to me that the Local Controller would be applying visual separation. It was this ignorance that led me to act as if there were two aircraft cleared at that time to fly directly into each other head-on. The Local Controller had turned the departure; but I did not call on the direct touch-line and also turned my arrival to the same cardinal direction; which put both on somewhat converging courses. Further vectoring and the issuance of an immediate climb clearance to the departure appears to have saved separation. Perhaps the SOP at facilities like mine; which allow the application of Visual Separation by the Local Controller and include an aircraft on the RADAR Controller's frequency should require in those instances that the Local Controller must notify the RADAR Controller immediately so that the RADAR Controller isn't put in the position to have to have such crucial faith in the Local Controller actually applying the Visual Separation and not (heaven forbid!) instead making a mistake that to be corrected; must be corrected immediately.
TRACON Controller reported being surprised by the opposite direction separation provided by the Tower between two Air Carrier operations. The reporter failed to realize the Visual Separation being applied by the Tower Controller.