Date: 201511
Local time of day: 0001-0600
Location: DFW.Airport, TX
Flight conditions: VMC
Light: Night
Aircraft: A321
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class B DFW
ATC / advisory: TRACON D10
Aircraft component: FMS/FMC
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Fatigue; Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Deviation - Speed All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Unstabilized Approach
Detector: Automation Air Traffic Control; Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Contributing factors: Human Factors; Aircraft; Procedure
Primary problem: Ambiguous

Narrative: Regional Approach: 'Flight XXX maintain 250 knots until further advised; I will call your speed reduction'Regional Approach: 'Flight XXX maintain 220' (we were about 15 miles out but it was the intercept angle that was suspect; normally in DFW they clear you for a visual but still give you a heading--which is what I was expecting)Regional Approach: 'Flight XXX maintain 180 to a five mile final cleared visual approach 18L' (problem was they had us on a 80 degree intercept)FCP altimeter setting inadvertently set to 1000 ft. Regional Approach: 'Flight XXX low altitude alert--check your altitude' (I know the formula for their computer is calculated not only on a hard altitude but also descent rate--ours was high)I had already realized we were not capturing the intended altitude of 2300 ft. (we were intercepting about a mile inside of UDALL) and was leveling off immediately before they even called us at or above 1500 ft (flight path; airport an runway all well in sight); but we had a high descent rate in an effort to get down and slow down. All visual cues were in sight while continuing but we were still fast due to the 220 and trying to slow before the turn which led to a slight overshoot but not severe. Pushed managed speed to slow to Vapp but airplane was not slowing for some reason (already had Gear Down and Flaps1). Discussion ensued on if approach was activated; etc. I disconnected Auto Thrust and airplane slowed nicely but not being accustomed to flying without AT anymore and did not have a good feel for it and we got slow--once again I immediately corrected but we did get the speed caution at the same time I was aggressively correcting but we did not approach a stall (Alpha floor was not reached or we would have seen TOGA which would have resulted in a GO Around). Stabilized approach parameters (VFR) reached prior to 500 ft. 'Stable' callout made and landed. Should have requested an extended downwind and not accepted the assigned speeds with an 80 degree intercept. Fatigue certainly a casual factor--inconsistent rest for all night flying.


Second narrative: We checked on with Regional Approach around FL190; and were given a clearance to maintain 11000. Below 10000; Approach told us to maintain 250 knots until further advised; they would call our speed reduction and that we were number one for the airport. A few minutes later we were given clearance to 5000. Open descent and flight spoilers were used to descend the aircraft. Around 14 miles from the airport we were told to maintain 3000 and reduce speed to 220 knots. I reported the field in sight; and we were cleared for the visual 18L. Approach told us to maintain 180 knots until a five mile final. Usually when cleared for a visual; a heading is given to join the final. I noticed we were on an 80 degree intercept heading to join final. The aircraft was then configured to flaps 1 and the gear down. I noticed we had a high descent rate in an effort to get down and slow down. Managed speed was selected; the autopilot and auto thrust were turned off; and the aircraft began to slow to final approach speed. The aircraft leveled at 1000 AGL so final flap selection could occur. Approach reported a low altitude alert and for us to check our altitude. I reported that we were leveling at 1000 AGL. As the aircraft leveled; the aircraft announced 'Speed'; this was immediately corrected and Alpha floor was not reached. The airport remained in sight the entire time; a slight overshoot occurred but was corrected immediately. Final flap selection was accomplished and the aircraft stabilized prior to the 500 ft callout. The aircraft landed in the touchdown zone. I would [suggest] asking for an extended downwind [next time] and to be more aware on visual approaches.


Synopsis: A321 flight crew reported becoming unstabilized during approach after being asked by ATC to keep their speed up. When managed speed was selected the aircraft did not slow down; so the autothrust was selected off. At 1000 AGL; ATC issued a low altitude alert and the aircraft announced a low energy warning. The aircraft was stable by 500 feet and a normal landing ensued.