Date: 201808
Local time of day: 1201-1800
Location: D01.TRACON, CO
Flight conditions: VMC
Light: Daylight
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B DEN
ATC / advisory: TRACON D01
Second aircraft: Citationjet (C525/C526) - CJ I / II / III / IV
Reporter organization: Government
Reporter function: Approach
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Workload; Situational Awareness; Distraction; Confusion; Communication Breakdown; Human-Machine Interface
Second reporter function: Approach
Anomaly: ATC Issue All Types; Airspace Violation 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 Provided Assistance; Flight Crew Returned To Clearance
Contributing factors: Human Factors; Procedure; Airspace Structure
Primary problem: Procedure

Narrative: I was working DR4; a departure gate to the south. Land north at DEN IFR. Land south at APA. I had a flight of F16s arrive from the southeast requesting the Sandbox. There were only a few arrivals to 34R; which could not come in on the approach with the Sandbox hot; so I called final to see if they were willing to accommodate it. Final said they would only have to slightly delay the arrivals for the Sandbox so it was approved. I said point out approved for the first downwind to vector around the Sandbox to the west in my airspace. Coordination was complete and I cleared the fighters to the Sandbox. TM (Traffic Manager) began to question the operation and said I could not do the Sandbox with aircraft on 34R; this got my immediate attention and I began to scan the airspace to see if I'd missed something; double checked that I was ok with final and explained to the TM what we had coordinated. In that moment I hear the SR4 Controller saying I'm sorry and Aircraft Y turns yellow on my scope; head on with Aircraft X climbing out of 100. My Aircraft Y was also climbing out of 100; I told him to stop his climb and turn to a 260 heading and issued traffic. He was slow to respond. I tried asking SR4 what he was doing several times; the only response I got was 'turning eastbound'. I stopped my Aircraft Y from climbing because I knew that SR4 had to get his aircraft above or he'd run into several other aircraft on the departure and arrival. Turning eastbound would mean he was entering the Sandbox; a protected area for the fighters. It was unclear what action he was taking. Turned out; SR4 also stopped the climb on Aircraft X who leveled at 108 and had separation errors with two other aircraft. Aircraft Y reported an RA and while I was straightening all that out I realized final had another aircraft on the downwind they were vectoring wide around the sandbox; this aircraft was not yellow on my scope and no coordination was done for a point out. I realize that the aircraft had to go that way to miss the Sandbox but with everything else I had going on; I did not stop my Aircraft Z from climb via in time. When I saw the two aircraft in close proximity; they were on parallel headings; mine was already climbing above with the arrival descending so I did not take any further action. Additional assistance by the Supervisor could've aided some of these situations. I would expect my Supervisor to be able to coordinate or offer an extra set of eyes but he did not come over. I have seen that particular Supervisor throw his hands up and imply there was nothing he could do to assist a Departure Controller in trouble. He is I believe uncomfortable and unfamiliar with the policies and procedures of the departure wall. Training on both familiarization and how to assist would be helpful.I noticed what seemed to be radar lag when I turned Aircraft Y; there seemed to be a significant jump on his track after what felt like a long time after I'd turned him. A calibration check on the radar if that's possible. I would like to see a best practices study on how to accomplish what we call the up and over with efficient coordination. Our SOP does not detail how SR4 can efficiently climb an aircraft to go through DR4's airspace and heading out the north and east gates. It is currently being done by a point out but there is so much other coordination to be done that steps can get missed. Because the up and over is frowned upon by some controllers; there is peer pressure to either not do it or avoid coordination all together. In this situation; I was very busy and SR4 was trying to do me a favor by working the aircraft; as he became more busy the coordination was not completed. Working the aircraft below the final would have added complexity and additional traffic conflict situations; that often lead to RA climbs; not to mention a delay to the aircraft. There are times where the up and over is so much safer and more greatly efficient that it is a greattool and worth further evaluation. There are also times where poor judgment is made and errors occur; usually with a lack of policy and proficiency.Coordinating the Sandbox could have been a contributing factor but I stand by my decision to do so. Because SR4 was busy with aircraft under the final airspace; and because there were arrivals coming in the SE; workload would have been higher and more complex if I'd decided to go under the final. It also would've caused several more traffic conflict situations. I'd like to see refresher training how to recover from an error. I was extremely frustrated that the SR4 controller was unable to tell me what he was doing with the aircraft. Logic would have told me that he had to continue climbing in order to miss the other aircraft but he didn't. Reinforcing right turns for head on conflicts along with vocalizing altitude would have been a help and a comfort.The Final Controller told me that the Feeder Controller was still working the downwind Aircraft Z that was on a vector to miss the Sandbox. Final was yelling for the aircraft as he saw the conflict with my departure. Final said that feeder would not switch the aircraft or respond. Final said he wanted to put the aircraft on a better heading to achieve divergence with my departure. Feeder controllers are much less familiar with departure traffic and are not accustomed to missing or even seeing departure aircraft. Refresher training for arrival controllers on departure procedures and traffic could benefit awareness.


Second narrative: Working SR4 with multiple VFR flight following; multiple APA departures/arrivals on frequency. A number of VFR callups were trying to check in. There was also a Class B violator that was being tracked and discussed which ended up being one of the VFR callups that I told to standby. Having been on position for over an hour with only moderate traffic; I don't think I was mentally prepared for the wave of traffic and requests that hit me. During the session I had climbed a number of east gate departures off of Runway 17L at APA via a right turn and over DEN pointing them out to DR4 due to there being less traffic in the way than a left turn off the deck and restricted to 080. When Aircraft Y departed in the right turn; I had to get divergence with Aircraft B; an APA inbound; before I could climb him. At that point I was dealing with a lot of traffic and attempted to hand Aircraft Y off to DR1. The tag was in handoff status for a minute or more and at that point I realized the DR1 controller was probably too busy to take the handoff so I climbed the aircraft but didn't realize that I had not done the coordination with DR4. DR4 was busy as well with coordinating the SANDBOX with all affected controllers and also had multiple DEN departures at the time. South gate departures were departing west of DEN probably due to the high volume of east gate departures which took me by surprised when I saw the conflict because with the closure of Runway 7/25; south gate departures have primarily departed off the east side. Aircraft X was climbing via the SID leaving 105 or so when I saw it; while Aircraft Y was climbing out of about 100. I immediately told Aircraft Y to stop the climb thinking that would be the best way to keep separation. I was trying to coordinate with DR4 but she was too busy; meanwhile the CIC was trying to tell me that a Cessna that I was vectoring was entering the SANDBOX. With all this I didn't realize that DR4 had stopped Aircraft X's climb as well. I did issue a turn to Aircraft Y but the closest separation was approx. 1.66 NM and 300ft vertical. Due to the turn issued Aircraft Y and because the SANDBOX was active; forcing arrivals to turn the downwinds to the west; Aircraft Y was closing in on Aircraft A who was level at 110. As soon as I saw this; I climbed Aircraft Y but separation decreased to approximately 1.68 and 900 feet. While this was going on I put Aircraft B on a northbound heading and descended to 080. I also to a handoff on Aircraft C at 090 inbound to APA from DR1. At the time of the handoff; Aircraft C was at 090 and I believed that even though Aircraft C and Aircraft B were converging; I would have separation. DR1; however; descended Aircraft C to 080; which was what they were supposed to do in that configuration; but I didn't realize it at the time due to everything else going on. Aircraft B and Aircraft C passed 2.75 NM apart at the same altitude.Procedures have been established to take APA departures eastbound at 080 from APA underneath DEN arrival airspace. That procedure certainly has benefits; and would have been better in this case; but on certain days that airspace can be packed with VFR traffic in the practice area as well as typically being used for APA prop arrivals from the east. There are a number of good ways to depart APA with east gate jets; however none of the options seem to be a good idea all the time. I think the APA departures should be looked at and explore other option or procedures. As it is; either way there are multiple frequency changes or coordination involved. There was also no one helping to watch the sectors or to help coordinate even though DR1; DR4; SR4 were all very busy.


Synopsis: Denver TRACON Controllers and air carrier First Officer reported multiple losses of separation and airspace violations.