Date: 201603
Local time of day: 1201-1800
Location: ZMA.ARTCC, FL
Aircraft: A319
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class A ZMA
ATC / advisory: Center ZMA
Second aircraft: A319
Reporter organization: Government
Reporter function: Enroute; Oceanic
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness; Time Pressure
Second reporter function: Pilot Flying; Captain
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Aircraft RA; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Airspace Structure; Human Factors; Procedure
Primary problem: Airspace Structure

Narrative: I had Aircraft X coming up from at 32;000 feet on the wrong transponder code which does not track up unless manually tracked up by the controller. I had several aircraft southbound climbing through the corridor towards TADPO. I had traffic head-on with Aircraft X at 31;000 feet that I could not descend the Aircraft X through so I called traffic and advised Aircraft X to expect lower soon. We had all the warning areas active with no activity in them and made it more difficult to turn aircraft to avoid a collision.  This is always the case when the warning areas go active.  I turned Aircraft Y to a 170 heading and advised the pilot to expedite through 33;000 feet and also turned the Aircraft X 20 degrees left. My turns should have been sufficient to avoid less than 5 miles however both aircraft had a TCAS resolution and Aircraft X said he was advised to climb at which point I advised him that the other [aircraft] was expediting his climb and to please descend; he went against my wishes. I believe I had 3 miles at the same altitude because Aircraft Y was advised by TCAS to stop the climb. They were both at 33;000 feet with 3 miles.  Had nothing else to say or do after that. I do believe that the warning areas along with TCAS made this situation worse.Getting rid of the warning areas surrounding the fixes that go through the airspace should be looked at for the future. There are more and more flights going to or through the airspace with restrictions of 15 miles in trail.  Not only is that difficult to do; the corridor is not wide enough to even have two airways run through it so both northbound and southbound are head on and the northbound need to descend into the airports and the southbound aircraft are all climbing. This situation is only going to get worse or the newer controllers will be unable to climb aircraft above 23;000 feet.  It is not a good and safe situation.  I have been working in this area for [many] years and the traffic has increased with no changes to the warning areas.  If this is not fixed then aircraft will have to have a ground delay program to overfly the [airspace] to this destination.


Second narrative: Center issued an immediate left turn to us for traffic avoidance. In the turn we received a TCAS RA to climb; which we complied with. Informed ATC that we were complying with a TCAS RA and climbing. ATC then issued a descent clearance to us. Informed ATC that we were unable due to the RA climb issued by TCAS. Once clear of conflict; confirmed our descent and heading clearance and resumed arrival. Asked ATC what happened and we were informed that company aircraft going opposite direction had not acted quickly enough on their clearance to climb and turn.Seems that maybe the ATC controller got a little behind if an aircraft not complying quickly enough to instructions caused another aircraft to receive an TCAS/RA.


Synopsis: A ZMA Controller descended one aircraft and climbed another aircraft head on. The Controller issued turns to the aircraft but had less than required lateral separation.