A319
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Confusion; Workload; Time Pressure; Human-Machine Interface; Distraction
Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Returned To Clearance
Human Factors; Chart Or Publication; Aircraft; Procedure
During descent on the JAGGR1 RNAV arrival we hit the HASHE intersection 400 FT above the maximum altitude for this fix. This was the first time either myself or the First Officer had flown an RNAV arrival into Denver. Just prior to this excursion ATC had issued us a speed reduction. We had been flying the arrival in a fully managed mode.Due to the proximity to the fix upon receiving the speed reduction the First Officer (who was the flying pilot) decided to select the new speed. This was a high workload phase of flight...we had just transitioned from the flight levels and were entering the altimeter setting at this time. In addition we were running the approach checklist and signaling sterile cockpit to the flight attendants.With everything going on I didn't see that the airplane was struggling to simultaneously go down and slow down at the same time until we were 0.7 NM from the fix. I saw that we were not going to make the restriction at HASHE and called that out to the First Officer. He immediately disconnected the autopilot in order to quickly increase our rate-of-descent; but we still arrived there 420 FT too high. ATC did not say anything and we continued to landing without incident.I feel that Denver Approach contributed to our problems here. Throughout the RNAV arrival we received three air speed assignments other than those published; two altitudes other than those published; and two different lateral clearances that differed from those published. Not only did we start getting confused about what exactly ATC was expecting from us due to the large number of deviations from what we had been 'cleared' to fly; but all of this data input into the FMGC does not make the Airbus respond well. It is slow to figure out the new vertical paths and when you combine this with unpublished speeds; it really freaks out the box. I simply don't understand the value of an RNAV arrival combined with a 'cleared to descend via' clearance...and then receiving SEVEN variation clearances to what's published. I can tell you that on this; my first DEN RNAV arrival; I strongly feel that we were led down a path by ATC that did not engender the level of safety that we normally have on arrival into Denver. I also don't think that the controllers that we dealt with today have any concept of how this many deviations from the 'cleared to descend via' clearance we received affects our ability to safely fly such a procedure.At the gate; we discussed what happened and how we managed to get ourselves high over this fix. I think I was trying to do too much at once (approach check; altimeter setting; sterile signal) during a period of time when my attention should have been 100 percent on the automation. I feel that in the future when I get changes to the RNAV arrival it will cue me in to being hyper-aware [to ensure] that the automation is responding [appropriately] to the revised constraints. I also think that we placed too much faith in the automation to quickly come up with the new path at the slower speed. I will definitely be more on guard on these DEN RNAV arrivals in the future...ESPECIALLY when ATC begins throwing out changes to the 'cleared to descend via' clearances.
We were planning on landing in DEN with 4.2 according to the box. MCI Center issued us a vector to the south to increase the spacing into Denver because the Approach Controllers now wanted 40 mile spacing as 'They are afraid they couldn't control the arrivals with 20 mile spacing.' With this vector behind other traffic we were now looking at landing in DEN with 3.8. We told him we didn't have a lot of extra fuel and then a few minutes later we were told they were fine with 20 mile spacing again so we got cleared direct to SLN.We talked about letting the box do its thing and let's see how this works out. We continued to DEN. We started the arrival at OATHE and had planned on letting the FMGC manage it all. Then we got cleared direct to DANDD. [We continued in] Managed Descent. A few minutes prior to reaching HASHE ATC asked us to slow to 230 KTS. So we pulled the speed. It appeared that the plane was just going to make the restriction. It wasn't until we were closer that we realized it wasn't going to make it. I turned off the autopilot; used the boards and pitched over smoothly and crossed HASHE at 17;420 according to the post flight report.
When ATC issued modifications to their 'descend via the JAGGR RNAV STAR to DEN' clearance; the flight crew of an A319 was unable to comply with the altitude restriction at HASHE.