Date: 201605
Local time of day: 1801-2400
Location: ZFW.ARTCC, TX
Weather elements / visibility: Turbulence
Light: Dusk
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class E ZFW
ATC / advisory: Center ZFW
Aircraft component: Autoflight System
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Human-Machine Interface; Communication Breakdown; Confusion; Workload
Second reporter function: Pilot Not Flying; First Officer
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Procedure

Narrative: Descending into DFW; early in the descent; we were re-cleared from the SEEVR arrival that was our filed route to the BRDJE arrival. The SEEVR arrival had been briefed along with the ILS 35R and we had been cleared to a lower altitude but not given a descent via. Subsequently we were cleared for the BRDJE arrival; set it up; confirmed the arrival and re-briefed. During that time we were interrupted several times by requests from the flight attendants. We thought all the bases were covered when ATC called and asked us if we were on the SEEVR or the BRDJE arrival. We responded BRDJE. We were passing 16500 ft and he told us to maintain 15000 ft. We then realized that we were in open descent and had just miss a restriction at BRDJE of 17000 ft. He did not indicate that there was a conflict and we were subsequently re-cleared to descend via the BRDJE.I believe that when we finished the setup we were in managed flight and can't explain being in open descent other than we missed a reversion during one of the distractions from the flight attendants. Also the similarities between the SEEVR and the BRDJE arrivals (many fixes in common but different crossing altitudes i.e.; the crossing at BRDJE on the SEEVR is between 12000 ft and 11000 ft and between Fl190 and 17000 ft on the BRDJE) may have contributed to our perception of the situation due to the fact that we had actually briefed both arrivals by then.


Second narrative: While this was going on we were contacted by the flight attendants multiple times. During this time the controller also assigned us a speed that was not published on the arrival; but we were told to follow speeds at SEEVR. We had briefed both arrivals and noticed that the fixes were similar; but the altitude crossings were different. While the changes to the arrival were entered into the FMS; there was a switch of modes from Managed to Selected that we were not aware of at the time.  He told us to level off at 15;000 feet and fly direct to SEEVR then descend via the arrival from there. There was no loss of separation and there was no deviation from the route due to other aircraft since there was no aircraft in our vicinity.


Synopsis: Descending into DFW on the SEEVR THREE RNAV arrival; the flight crew was instructed to cross the SEEVR waypoint between 13;000 ft to 16;000 ft. The flight was re-cleared on the BRDJE THREE RNAV arrival with a new crossing restraint yet somehow the MCP transitioned to SELECT and the flight crew was unable to level for the constraint in time.