An A321 flight crew reported missing a crossing altitude on the GEELA 4 Arrival to PHX. Both pilots mentioned the 'gotcha' elements of the crossing restrictions in this arrival that make it difficult to comply.
Synopsis
An A321 flight crew reported missing a crossing altitude on the GEELA 4 Arrival to PHX. Both pilots mentioned the 'gotcha' elements of the crossing restrictions in this arrival that make it difficult to comply.
Narrative
Prior to descent to the PHX airport both the First Officer and I were preparing some descent crossing restrictions into the FMGC. During this preparation we had discussed and input an additional restriction as per NOTAM to expect to cross GEELA Intersection at or below 16;000. Later during our descent phase ATC had cleared us to descend to cross GEELA at or below 16;000 and cleared to descend on the GEELA FOUR arrival; Runway 7R transition. I then selected 5;000 FT in FCU altitude window for the CAGOR restriction and confirmed with First Officer (pilot not flying). During our descent the aircraft and FMGC indicated on profile. At GEELA Intersection I recognized that the restriction at PUNNT would not be made. The First Officer as quickly as possible notified ATC of this situation. ATC then gave us a clearance to maintain 8;000 and slow to 210 KTS. Ten seconds later another Controller on the same frequency asked us to please notify them earlier than the point at which we were. I apologized and told him that we had not discovered it until passing GEELA Intersection. We proceeded to descend to 8;000 FT and then were cleared to intercept the Runway 8 final approach course and then later cleared the visual approach to Runway 8.This event occurred due to the fact of inputting a hard altitude of 16;000 into GEELA; when clearly an at or below 16;000 is needed and due to the fact there is only 4.4 nautical miles between GEELA and PUNNT. By rough calculations you would need to cross GEELA at 12;000 FT in order to make PUNNT at 11;000 FT with a slight tailwind; which by you would be descending below the minimum enroute altitude (MEA) of 13;000 FT between HYDRR and GEELA. In the future when reviewing descent profiles I would look closer at changes (i.e. NOTAMS) that change charted restrictions as to their legitimacy on attainable descents from one intersection to another. With further research; I have found for example EAGUL FOUR arrival and others like it that provide at or below altitude restrictions that give ample distance to meet the next restriction.
Second reporter narrative
Using the term 'at' is part of what caused this to happen. If the clearance was 'below 16;000' or an altitude window it would have avoided 16;000 from being inserted into the MCDU. It does not work. This is a bogus clearance and needs to be revised immediately.
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.