Date: 201410
Local time of day: 1801-2400
Location: DEN.Airport, CO
Flight conditions: VMC
Light: Daylight
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class E ZDV
ATC / advisory: Center ZDV; TRACON D01
Aircraft component: MCP
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Distraction; Workload
Second reporter function: Pilot Flying; First Officer
Anomaly: Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Air Traffic Control; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance; Flight Crew Became Reoriented
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: We were descending on the FRNCH arrival into DEN. At approximately 10-15 miles outside SKARF atc asked us to speed up until SKARF; and then fly published speeds at SKARF. (This really confused me because we wouldn't have enough time before SKARF to speed up and then slow again. Also; there is not a published speed at SKARF.) When I read back the atc request he gave us a frequency change to DEN approach. I dialed in the new frequency as my FO changed the altitude alerter to the next step down altitude. When he called; '15;000 set' I looked up and verified the altitude he had set as 15;000 feet. The altitude that should have been set was 17;000 feet for TOMSN. During our confusion he miss read the chart and dialed the altitude for DORKE instead of TOMSN. (DORKE is the next fix after TOMSN and close together on the chart) I failed to check that altitude against the chart as the next step down altitude because; 1- I was confused and looking at the chart for a 'published' speed at SKARF. 2- We were discussing the short distance to SKARF and the speed assigned; and our confusion over a lack of a 'published' speed at SKARF.3- Because I was dialing in the hand off frequency and verifying the ATIS letter code for check in. When I did check in with DEN approach I reported; descending through one six thousand eight hundred on the French arrival with the ATIS letter code. The controller answered back with a query on our altitude and said; 'I see you at one six thousand three hundred. You were supposed to level at one seven thousand. Stop your descent; raising terrain.' I reported back that would stop the descent and that the terrain is in sight. The controller responded; 'Well; in that case descend to one five thousand.' We complied and rejoined the arrival with no further incidents. Confusion; task saturation; being rushed to find the speeds and comply. Pay better attention to actions of co-pilot. Don't trust that they have entered the correct altitude. When verifying altitude in alerter don't just very that it is the altitude that they said but; stop other tasks and verify that it is the altitude that should be entered.


Second narrative: We were cleared to descend via the FRNCH Two arrival into Denver. We leveled off just prior to TOMSN and began to slow. I set the altitude to the next fix and the Captain mentioned to watch my speed. We slowed and began a descent. I noticed late that we had not yet crossed TOMSN and the approach controller question our altitude. He then cleared us to 13000 feet and we continued into Denver.The altitude deviation was caused by initiating a decent prior to the waypoint with a crossing restriction. The Captain and I were having a conversation on descent and that contributed to the event. Being more attentive to the speeds and crossing restrictions on the arrivals. Confirming altitudes with the other crew member prior to initiating a decent.


Synopsis: CRJ-200 flight crew reports being distracted during the FRNCH RNAV arrival to DEN and the First Officer sets 15;000 for the TOMSN crossing which should have been 17;000. The Captain confirms the altitude without checking and ATC detects the error.