Date: 201307
Location: ZFW.ARTCC, TX
Flight conditions: VMC
Light: Daylight
Aircraft: A321
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Airspace: Class A ZFW
ATC / advisory: Center ZFW
Second aircraft: EMB ERJ 135 ER/LR
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Fatigue; Human-Machine Interface; Time Pressure; Training / Qualification; Workload; Confusion; Communication Breakdown; Situational Awareness
Second reporter function: Pilot Not Flying; Captain
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Inflight Event / Encounter Fuel Issue; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Aircraft RA; Automation Aircraft TA; Person Flight Crew; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Diverted; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Contributing factors: Weather; Staffing; Procedure; Human Factors; ATC Equipment / Nav Facility / Buildings
Primary problem: Staffing

Narrative: We were established in holding pattern over CAPTI Intersection at our assigned altitude of FL240. We received TCAS TA which was followed by TCAS RA from traffic descending. We followed TCAS RA commands and descended to 23;500. We notified Center; and when clear we climbed back to FL240. The traffic was a CRJ. Center cleared them to climb and/or maintain FL260. Possible ATC or pilot error; DFW was not taking any aircraft due to weather over the field. It was a very busy time for ATC and air crews. Many aircraft were holding; and making decisions to divert to alternate airports. We ended up diverting to for fuel.


Second narrative: ZFW Center informed us to expect holding 'As Published' at WEIRS Intersection on the CQY7 STAR arrival due to thunderstorms over DFW. We slowed to approximately 200 KIAS. Later ZFW Center instructed us to proceed to WEIRS Intersection. Approaching WEIRS Intersection; ZFW Center then re-cleared us direct CAPTI Intersection and to 'hold as published' at FL240; 10 mile legs; and gave us an EFC. Once confirming the correct holding definition information was set in FMS2 (pilot flying); I began to enter the same in FMS1 with conventional VOR navigation underlying the GPS information. At approximately 3-4 NM from CAPTI Intersection; a red TCAS 'Resolution Advisory' displayed on my MFD screen. The aural TCAS commanded to 'Climb; Climb' and I visually acquired a B737 or A320 at the 10 o'clock position on a converging course. The aircraft appeared to be at the same or slightly lower altitude of FL240. I reacted by pulling the control yoke aft and pushing both thrust levers full forward to the stops. We climbed to FL251 and ZFW Center cleared us to descend to FL220. I informed ZFW Center of the RA and gave control back to my First Officer and turned the autopilot back on. The First Officer never visually acquired the intruder aircraft as he was seated on the opposite side. There was another aircraft holding at CAPTI Intersection at a higher altitude during this event. Several factors coincided to cause this event: Multiple aircraft holding at the same STAR arrival intersection; a last moment ATC clearance to hold at another intersection; an ATC Controller change with several aircraft holding at the same fix which increases the risk.Holding at the WEIRS Intersection would have been less flight crew workload as it was on our original STAR clearance. There was sufficient time to input the holding definition into the FMS navigation units and verify the information by both pilots.


Synopsis: In the midst of a chaotic ZFW ATC scene an A321 and an E-135 were both cleared to enter the hold at CAPTI Intersection at FL240. Rapidly sequential TA and RA commands to both aircraft prevented a disastrous culmination. Five reports from pilots and controllers involved provided a close up look at both sides of the events. Excerpts from the final ATC report are must reading to obtain the flavor of the event.