Date: 201708
Local time of day: 1801-2400
Location: ZMA.ARTCC, FL
Flight conditions: Marginal
Weather elements / visibility: Cloudy; Thunderstorm; Rain
Aircraft: Large Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZMA
ATC / advisory: Center ZMA
Second aircraft: Medium Transport
Reporter organization: Government
Reporter function: Enroute; Instructor
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Training / Qualification; Fatigue; Situational Awareness; Workload
Second reporter function: Enroute
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Air Traffic Control; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic
Contributing factors: Company Policy; Airspace Structure; Human Factors; Weather; Procedure
Primary problem: Company Policy

Narrative: I was the Instructor at the time of this incident. We had a Handoff/Assist positon. Aircraft X was level at 35000 feet deviating slightly left of course for weather. Aircraft Y was slow climbing out of 33000 feet to 37000 feet. Aircraft X was indicating approximately 460 knots groundspeed with Aircraft Y indicating 375-380 knots. Aircraft Y was approximately 6 miles diagonally behind Aircraft X. Vector lines also concurred with this; showing that they would be 6 miles apart in 1 or 2 minutes. I assessed this situation and agreed with what the vector lines and ground speeds were showing. Consistent to my training; Aircraft Y should pass directly behind at 6 miles from Aircraft X. As Conflict Alert activated; my trainee was working on another issue south of this situation which my trainee resolved.He looked at this situation. I told him to turn Aircraft Y 20 degrees right of course to run behind Aircraft X. As Aircraft Y was climbing through 34100 feet the trainee asked me if he should descend him back down to 34000 feet. I told him 'no'; as this instruction would induce confusion with the pilot and would not solve the conflict possibly causing him to speed up more by the time it's finally understood. Aircraft Y passed behind Aircraft X at 4.93 miles; resulting in a loss between the two aircraft. I take responsibility for my actions; and admit that I misread the situation. During this entire event; the sector had a full En route Decision Support Tool (EDST) and the sector's Monitor Alert Parameter (MAP) number was at the original number of 18. The actual value was borderline to this number; at 17-18 the whole time. Future 15 minute increments were showing red. This MAP value does not change when there's weather; which I believe is a safety issue as it lulls people into a false sense of security. Based on that logic; we can work the same amount of planes with 100% weather as if we had 0 weather. There was a significant line of weather developing causing numerous deviations and frequency congestion. The volume of traffic for this sector was significant even without the weather in the north side of the sector. Routes were closed to our northeast; and then reopened; which resulted in a significant increase of over flights to our sector. The Q routes were closed; which resulted in aircraft going over a fix that would have normally exited our sector significantly faster. Throughout this whole event; no Traffic Management Issues (TMI) were applied to our sector to reduce the traffic volume; and help alleviate our congestion. The Supervisor recognized how complex that it was; and said 'If you need help; your tracker is right behind you; just grab him.' He was looking out for the situation; whereas Traffic Management Unit (TMU) failed to help our sector from becoming too complex. Compounding the situation; both the trainee and I were 'assigned to duties' since XA00. This occurred 2 hours and 17 minutes without being offered a break away from the operational area.. We both were plugged in for approximately 30 minutes; took a 30 minute break; and went to our mandated team training. From XA00-XB00; we were in our mandated briefing and training; and then told to report to the floor. We were plugged in at this sector from XB00 to XC55; a 1 hour and 55 minute plugin; but being assigned to duties for more than 2 hours and 55 minutes without a mental break or rest. Supervisors in the area do not believe that 'being assigned to training' is the same as being plugged in at a sector; but both are mentally taxing. I believe that I was not as responsive as I would have been within the first hour; even two hours; of working this sector. I believe that this length of plug in negatively affected the trainee's decision making as well.Throughout the whole summer; we are forced to push aircraft through small gaps in extreme precipitation and convective activity. Unfortunately; this is an example of that. Because of this; workload greatly increases exponentially in the sector as aircraft are deviating that normally we can run parallel; and they're dangerously close to convective weather activity. There continue to be no plans to fix this; or change this; we just continue to run aircraft through the weather until something terrible happens.I would require that the MAP value changes to reflect the current conditions in the sector; as required by the Order. We currently do not do this. As such; when the sector is borderline RED or Yellow TMU should have to advise the supervisor what actions they have taken in order to resolve it. If the sector is already inundated with weather; the more significant the plans should be in order to alleviate it. For example; once some of the routes opened back up in this case; they could have offered the routes to about 10 aircraft; which would have significantly reduced the workload in this sector at the time of the incident. Additionally; when there is weather; especially developing lines of severe weather; as this was; plans should be drawn up on how they will change the departures as the weather progresses. This should be done at TMU and at the management level; so that the sector team; who is already extremely inundated with problems; does not have to worry about this. All they have to do is turn around and tell a Supervisor; 'Hey this isn't working; what's the next plan?' Currently; this happens; and then it's up to the sector team to devise a new plan. If the opposite was true; then the following aircraft could already be executing the next few plans; without sector overload.We routinely get away from the idea of keeping aircraft away from severe weather; instead; we run aircraft as close as 3 or 4 miles away from heavy precipitation as seen in the situation above with BOTH Aircraft Y and Aircraft X. When weather is developing; we need to move our traffic away from the precipitation to the recommended 20 miles. Aircraft should not be allowed to depart on routes that take them less than that separation (20 miles) to the weather. If they deviate that direction; that is their choice; but we are setting ourselves up for failure by letting them depart on routes that are filed through areas of extreme precipitation and convective activity. I would also suggest significantly briefing supervisors on fatigue requirements; and the mental impairment caused when controllers are on position/assigned duties for more than 2 hours. The cognitive process breaks down; and results in judgment errors that normally wouldn't happen when the controller is fully rested.


Second narrative: [Report narrative contains no additional information.]


Synopsis: Air Traffic Controller and trainee reported a loss of separation between aircraft deviating for weather.