Small Aircraft; High Wing; 1 Eng; Fixed Gear
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 7.5
Confusion; Communication Breakdown
ATC Issue All Types; Conflict NMAC; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Separated Traffic
Human Factors
Aircraft Y was originally told to go to RWY 5 for a straight out departure; but he went to RWY 23. Aircraft X was doing full stop taxi backs on RWY 25. When Aircraft Y was ready for departure; he was told to make a right downwind departure (standard is left due to RWY 7/25 traffic) to keep noise away from the homes south of the airport. Aircraft X was cleared to land RWY 25. I told Aircraft Y to begin his right turn when he was west of RWY 16/34 (as he was heading for another noise sensitive area); and he did so. Then passing the Tower on RWY 25 is Aircraft X powering up as he did a touch and go; not a full stop as instructed. I told Aircraft X to remain low through the intersection (as Aircraft Y was just west of it at approximately 600 AGL) for traffic. I would guess they passed about 300 FT. Aircraft X was told to call the Tower for a possible pilot deviation.After speaking to the pilot of Aircraft X; he knew what he did wrong. His mistake almost caused a mid air. At MRI we have issues with pilots doing what they want - vs. - doing what they are told (i.e. Aircraft Y going to 23 - vs. - 5).  FSDO needs to become more active in pilot education and if need be; pulling certificates. In today's world; I see us; the air traffic controller becoming more of an instructor than ever before at the GA level; as a large portion of GA pilots just do not know what to do; or say. Maybe due to lack of time in the airplane.
Controller reports of NMAC due to aircraft that was supposed to make a full stop elects to make a touch and go coming into close proximity of another aircraft in the pattern.