Widebody; Low Wing; 4 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 19
Training / Qualification; Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action
Human Factors; Procedure
Training in progress; Aircraft X working VFR in the east practice area; wanted to pick up IFR was almost at the boundary with Pueblo at 081MSL we pointed him out to PUB approach gave him a clearance and started him flashing to ZDV41; then tried to call them; they would not answer so I tried to call them on the dial line and tell them what he was doing. After I hung up I saw an Aircraft Y at 160 I told the trainee to stop Aircraft X at 150 then observed the Aircraft Y descending to 150; the trainee then descended Aircraft X to 140; meanwhile I am trying to get 41 on the shout line; they answered and said 'standby' finally they answered and said Aircraft Y has Aircraft X in sight maintaining visual; at which point we shipped the aircraft. We should have told Aircraft X to maintain VFR; point him out to PUB and then switched him to ZDV41 for them to issue the clearance.  My assumption that they would answer the line and take a handoff was wrong.
Aircraft X was climbing on an IFR flight plan while transiting from COS. During the climb; approximately 15-20 nm west of PUB; on J64; Springs Approach/Departure cleared Aircraft X to 16000 feet. During that climb; altitude clearance was subsequently amended to 15000 feet. When approaching and leveling off at 15000; a TCAS resolution advisory was activated commanding a descent. Nearly simultaneously; Aircraft X was instructed by ATC to immediately descend to 14000 feet. The flight crew recalls that Aircraft X was being controlled by [Colorado] Springs approach/departure at the time. We were switched to Denver Center nearly immediately afterwards. I later learned we were in Denver Center's airspace (see below). The RA commands to descend were immediately followed after disconnecting the autopilot; We passed approximately 500 feet nearly directly below a regional jet (call sign Aircraft Y) heading north descending into the Colorado Springs area. The pilot not flying (PNF) informed ATC that we had reacted to a TCAS RA. The rest of the flight proceeded as planned.After landing; I called Springs approach to find out details about the incident. I was referred to Denver Center as I was told the incident occurred within Denver's airspace. I finally spoke to the operations manager. He spent approximately 1 hour investigating before returning my call. When we subsequently spoke; he let me know that there was no pending action against the pilot; and that there seemed to be a coordination issue on their end. I believe he was referring to the hand off between Springs approach/departure and Denver Center.
Pilot and Controller report of a situation where the pilot had an RA and the Controller had issues trying to hand off the aircraft. Two aircraft came close to each other and the pilot reported receiving an RA and descending to clear the aircraft. Controller reported making an aircraft IFR; having problems handing it off to the correct sector; and then having a loss of separation.