EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Distraction; Workload
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Became Reoriented
Human Factors; Procedure
The flight was relatively short and we had some weather to pay attention to near the CVE intersection which begins the DRLLR ONE RNAV ARRIVAL. We briefed the arrival and approach for 26R and I was checking the fuel and getting the ATIS and messaging Dispatch as my First Officer went through the brief for our arrival. I might have taken a radio call or the Flight Attendant called at the start of the brief; but somehow I got distracted and didn't hear the First Officer say that he was briefing the GUSHR ONE RNAV ARRIVAL. Both arrivals have coincidental fixes and as he went through those it sounded like he was briefing the DRLLR ONE which he put in the FMS. I had checked the FMS for the proper altitudes and speeds for the DRLLR ONE and knew that it was properly set up; but failed to notice he was locked in on the GUSHR ONE in his mind. We had descended to 27;000 FT and passed REFYN when we were given a heading of 200 degrees and a descent to 24;000 FT. We were cleared direct to MPORT and told to descend via the DRLLR ONE except after DRLLR maintain 12;000. I read that back to ATC and set in 12;000 in the FMS over the fixes from DRLLR and beyond. I repeated the instructions to my First Officer as I was making the change in the FMS and he acknowledged it. As we started down I said that I was going to say goodbye to the passengers and be off the radio. I said goodbye and gave the passengers the arrival gate information and IAH weather and thanked them.  When I returned to the radio; we were given a handoff and I started to make the frequency change and re-engaged my scan and noticed that we were about to descend through 15;000 just before MPORT which had a restriction of 280/19;000-16;000. I asked the First Officer if we were still descending via the DRLLR ONE and he said he thought we were descending via the GUSHR ONE and I had him level off at 15;000. I called ATC and told them that we were descending via the DRLLR ONE but were at 15;000 just before MPORT and were trying to make it down for 12;000 after DRLLR. ATC said to maintain 15;000 and make the frequency change. I checked in with Approach and they gave us 15;000 descend via the DRLLR ONE. I asked for clarification to ensure that we were not planning to maintain 12;000 after DRLLR and he said that the Descend Via cleared the 12;000 restriction and I said that I understood but wanted to verify that point. My First Officer said that he somehow got the GUSHR ONE in his mind and was trying to cross MPORT at 12;000; which I don't think we would have had enough time and distance to make if that had been our instructions; so I was perplexed as to how that got in his head; but as the Captain I should have caught it before it went too far; and didn't. I plan in the future to make sure that the brief is more of a joint task than it was in this instance and make sure that both pilots are verifying all the details together in the FMS as well as on the charts; as I normally do; but failed to do so in this situation due to the workload etc. I will do more jointly involved briefings; instruct myself and future first officers to recognize and verify each descent point and crossing restriction to each other before leaving the present altitude even when one is off the radio; it can be done with a nudge and a point and acknowledgement while the other guy is off the radio; and I will make it a point to repeat multiple times the names of the SIDs and STARs that we are planning to use in order to make sure both pilots are keenly aware of the proper procedures to follow. I think setting the bottom altitude at each fix in the altitude alerter even on OPD arrivals will be a good cross check to avoid this situation again; even though the Training Center stresses putting in the first hard altitude on ODP's as the preferred method. I; also; will have the flying pilot repeat exactly what he is doing when the NFP returns to the radio as a way to re-verify their shared mental model. The Company can remind our pilots that there are procedures out there with coincidental fixes but different names and restrictions and re-stress the importance of dual verification to avoid our situation.
We were assigned DRLLR ONE RNAV arrival; CVE transition and that was correctly imputed into the FMS on the ground. I however; briefed and descended believing I was on the GUSHR 1 RNAV which also originates off CVE and shares many of the same fixes. We were instructed descend to FL270 then down to FL240 on a heading of 200. We were cleared to MPORT and descend via the DRLLR 1 arrival except maintain 12;000 after DRLLR. I was in the mindset that we were on the GUSHR 1 arrival and I had incorrectly attempted to cross MPORT at 12;000 feet. Because I was looking at the wrong arrival plate; I should have crossed MPORT between 16;000 and 19;000 as required for the DRLLR ONE. At 15;000 and prior to MPORT we noticed we were 1;000 feet low to the restriction as I had referenced the wrong arrival plate. We notified ATC and we were re-cleared to level off at 15;000 then descend via the DRLLR ONE arrival. The approach and landing were uneventful into IAH. New arrivals into IAH; ATC instructions modifying the arrival; lack of communication and verification [caused this event]. In the future; arrival briefings on my part will utilize the shared mental model; by ensuring there is no question as to what arrival; transition; and approach we are on.
EMB-145 flight crew reports being assigned and correctly entering the DRLLR 1 RNAV into the FMC prior to departure. Prior to descent the flying First Officer briefs the GUSHR 1; which uses many of the same fixes as the DRLLR 1 with different crossing restrictions; but the Captain does not catch the error. After returning from saying goodbye to the passengers; the Captain notes they have descended below a DRLLR 1 crossing altitude and questions the First Officer.