Date: 201812
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Aircraft: A319
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Fatigue; Situational Awareness
Second reporter function: Instructor; Captain
Anomaly: Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Undershoot; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: We were descending into ZZZ after a long day of day 1 IOE training; delays at ZZZ1; and bumpy rides. I programmed the FMGC to cross ZZZZZ intersection at 16;000 [feet] per ATC clearance. Because of the long day and my lack of focus; I failed to back up the automation to make sure it would cross at the required altitude.The Airbus did a 'soft level off;' which I failed to recognize immediately; and we ended up being 300 feet high at ZZZZZ. ATC didn't say anything and we did not appear to have had any loss of separation with other aircraft.


Second narrative: I was assigned to fly to ZZZ as a LCA [Line Check Airman] to conduct [line check] for a new Captain. This was the first day of the trip. Additionally; this flight was the third of the day. All three flights were at night; in the weather; and had turbulence throughout.We were delayed on our last flight by approximately 30 minutes in order to wait for connecting passengers. This added to our long day.Our flight was flying off-shore to avoid severe weather and were getting light to moderate turbulence for most of the flight. While descending on the RNAV arrival; ZZZ Center cleared us direct to ZZZZZ and to cross at 16;000 [feet]. An early descent was initiated by the Pilot Flying (new Captain) in an attempt to find a smooth ride at a lower altitude.She initiated a managed descent and we descended at 1;000 FPM per the descent schedule when descending below profile. I observed that the ND displayed the appropriate symbol where we would intercept the vertical profile approximately 15 miles prior to ZZZZZ.We did manage to find some smooth air and the seatbelt sign was turned off. I made a PA informing the passengers that the sign would only be off for about 10 minutes.While descending through FL180; the turbulence returned. I selected the seatbelt on and informed the passengers that they needed to be seated for the remainder of the flight. While I was making the PA; ZZZ Center handed us off to approach. The Pilot Flying handled the call but read back and selected the wrong frequency.Once I completed the PA; I returned to handling the radios. It took several attempts to determine the correct frequency and to check in with ZZZ Approach. After establishing communications with Approach; we were given a descent. It was at this point; I observed the FMC. It indicated we crossed ZZZZZ at 16;300 [feet].We discussed that the aircraft had been in a managed descent and had leveled off at 16;000 [feet] after passing ZZZZZ. Once again; the insidious nature of the A320 had caught us off guard.The A320 will appear to be complying with the FMGC programming to meet crossing restrictions; but will revert to a 1 G level off. This often results in the flight being high without complying with the programmed restriction.Both the new Captain and myself have flown the A320 for many years and are well aware of this. In spite of all the experience we have; distractions and fatigue contributed to us missing the restriction.A solution needs to be found with the programming logic of the A320 and how it prioritizes crossing restrictions. I understand that giving passengers a comfortable ride is important and a 1 G level off does help. However; this should not be a priority over crossing restriction compliance; which is a safety of flight issue.


Synopsis: A319 flight crew reported being too high at a crossing restriction because the Airbus crossing logic is flawed.