Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 1
Situational Awareness; Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Airport; Airspace Structure; Human Factors; Procedure
Aircraft X was conducting a banner drop operation. I approved the Banner drop operation. We had a crosswind of about 060 degrees at 6 knots. As Aircraft X dropped the banner and started to climb upwind; Aircraft Y requested a right crosswind departure off of Runway 28R. I cleared Aircraft Y for takeoff. Aircraft X requested to land on Runway 10R because of the crosswind. I advised Aircraft X as he was downwind to make a 180 degree turn and make right traffic for Runway 10R. Aircraft X acknowledged and made a 180 degree turn and an unauthorized short approach at the approach end of Runway 10R. Aircraft Y was still on Runway 28R; so I instructed Aircraft Y to cancel take off clearance; hold position; Aircraft Y did not acknowledge and began rolling. Aircraft X was short final and almost touching down as Aircraft Y became airborne. Simultaneous opposite direction may have occurred as Aircraft Y departed and Aircraft X landed. I would recommend clarification on the rule of Simultaneous Opposite Direction Separation.
Local Controller reported that an aircraft departed at the same time as an aircraft was landing on a parallel runway in the opposite direction. Contributing was the landing aircraft making an unanticipated short approach and the departing aircraft not acknowledging their takeoff clearance being cancelled.