Date: 201203
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Aircraft: Stratolifter (C-135 / 717)
Operator: Military
Operating under: Part 91
Flight plan: IFR
Flight phase: Cruise
Airspace: Class D ZZZ
ATC / advisory: TRACON ZZZ
Second aircraft: Iroquois 212/214
Reporter organization: Government
Reporter function: Departure; Approach
Reporter qualification: Air Traffic Control Fully Certified
Second reporter function: Approach; Departure
Anomaly: ATC Issue All Types; Conflict NMAC; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: A KC135 was handed off from East RADAR to West RADAR on a heading of 210; inbound for the airport requesting ILS approach to Runway XXL. I was training a Developmental who accepted the hand off and turned the aircraft to a heading of 220. At that same time there was a B212 helicopter maneuvering in the southeast practice area. The Developmental instructed the B212 to fly no further west than their present position. There was no response from the helicopter. The KC135 advised that he had traffic at his 12 o'clock and five miles same altitude. The developmental told the KC135 that the aircraft was a helicopter and would maneuver no further west then his present position. The KC135 advised that he was climbing for traffic. The helicopter reported the KC135 in sight when the aircraft were 2 miles and 700 FT apart. The helicopter was told to maintain visual separation from the KC135. The helicopter did not respond.


Second narrative: I was training in West RADAR. A KC135 was IFR and level at 030 on a 210 vector for an ILS Runway XXL. A VFR helicopter was maneuvering approximately 10 miles southeast of the airport. The altitude was approximately 029. The KC135 reported traffic at 12 O'clock and 5 miles at same altitude. I tried to reach the helicopter and instruct him to maneuver no further west than his current position anticipating that with a slight turn; the KC135 would pass by him with sufficient lateral separation. The helicopter did not respond to my transmission. I turned the KC135 10 degrees to a 220 heading and informed him that the helicopter would remain southeast of him. I said this to the KC135; because I was confident that I would be able to reach the helicopter. Instead; it took two additional transmissions for the helicopter to respond with the traffic insight and I instructed him to maintain visual separation/caution wake turbulence. During my attempt to regain communication with the helicopter; the KC135 advised that he was climbing to avoid traffic. He leveled at 040 and then descended back to 030 once he knew the traffic was maintaining visual separation. The KC135 stated on frequency that if he would not have climbed; he would have 'hit that guy' Later investigations showed that the KC135 passed 700 FT above and 2 miles laterally from the helicopter. I should have taken more positive control and turned the KC135 farther away. I should not have been so fixated on regaining communication with a helicopter; when I could have easily turned the aircraft I had direct communication with. I recommend more monitor time with CPC's to gain more perspective and professional knowledge of the position.


Synopsis: TRACON Controller providing OJT described a NMAC event when IFR military traffic took evasive action to avoid a VFR helicopter conducting practice maneuvers. Traffic had been issued by the Developmental.