Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Confusion; Human-Machine Interface; Situational Awareness; Troubleshooting; Workload
Aircraft Equipment Problem Critical; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance
Flight Crew FLC Overrode Automation; Flight Crew Returned To Clearance
Human Factors; Procedure; Aircraft
We were told to cross ZZZZ1 at FL230 and 280 KTS. We had it programmed CORRECTLY into the FMS. We both checked it several times. The airplane started down and we were ON THE PATH. The magenta donut was in the middle. The PROG page showed us 0 vertical deviation. The restriction was the correct color on the flight plan page. About 20 miles from ZZZZ1 we determined that we were not going to make ZZZZ1 at FL230. We were too high. We both looked at the FMS and it was simply not working right. There's some kind of bug in the ZZZZ2 arrival programming. We disconnected the autopilot and pushed the nose over and descended at about 5;500 to 6;000 FT per minute and ended up crossing ZZZZ1 about 1;000 FT high. There was no traffic on the TCAS and center didn't say anything so we didn't feel like there was a traffic conflict. There's a software bug or two in the ZZZZ2 arrival. We would have missed the first couple of crossing restrictions at the rate it was descending.The flight standards group is going to have to come to grips with the fact that the ZZZZZ arrival is full of bugs. This was not a case of a low cruise altitude causing the first restriction being deleted. It was there FL230 and 280 at ZZZZZ. The flight plan page on the FMS showed the restriction at ZZZZ1 in the proper color (not amber). The donut was in the middle. This was not an entry error. This was simply a bug in the operating system. Denying the problem exists won't make it go away. Why do we have so many altitude errors on this arrival?
An air carrier Captain reported the failure of the autoflight system to comply with the altitude and speed restrictions on arrival. He believes repeated instances of non-compliance are indicative of a programming error.