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Md-11 captain reported difficulty complying with multiple short-notice clearance changes on arrival into phx.
| Attributes | |
| ACN | 1398306 |
| Time | |
| Date | 201610 |
| Local Time Of Day | 0001-0600 |
| Place | |
| Locale Reference | P50.TRACON |
| State Reference | AZ |
| Environment | |
| Flight Conditions | VMC |
| Light | Dawn |
| Aircraft 1 | |
| Make Model Name | MD-11 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Descent |
| Route In Use | STAR EAGUL6 |
| Flight Plan | IFR |
| Person 1 | |
| Function | Captain Pilot Flying |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Events | |
| Anomaly | ATC Issue All Types Deviation - Altitude Crossing Restriction Not Met Deviation - Altitude Overshoot Deviation - Procedural Clearance Deviation - Speed All Types |
Narrative:
Captain was PF (pilot flying). We were approaching zuni for the eagul 6 RNAV STAR into phx and were subsequently cleared direct to homrr intersection and cleared to descend via the eagul 6. Approaching FL200 we were handed off to phoenix approach who directed us to delete the speed restrictions. The first officer (first officer) deleted the five speed restrictions in front of us on the arrival. The aircraft had just adjusted the profile for roughly 300 KIAS when we were told to comply with the speed restrictions. We were 4-5 NM from homrr with a restriction of 250/17000 feet. I bow-tied the speed and applied full spoilers while the first officer went back to reinserting the remaining four speeds. We made the altitude restriction at 17000 feet but were roughly 20 kts fast as we crossed homrr. As soon as the FMS sequenced homrr the autopilot commanded an aggressive descent of 5500-6000 feet/minute. The next waypoint was bohtx with an altitude restriction of 13000-14000 feet. As soon as I recognized the descent I reverted to V/south and commanded a level off. We overshot the 13000 foot restriction by about 300 feet one mile short of bohtx. After bohtx we continued the arrival without any further problems. ATC did not say anything about either the airspeed or altitude deviation.being cleared to descend at a higher than normal speed; then being told to meet speed restrictions in close to the first waypoint put us behind to the point that we couldn't make both the airspeed and altitude restrictions. I felt the altitude was more important at that time and did the best I could with the speed. I don't know why prof (profile) commanded such an aggressive descent; but by the time I caught it we were too close to the 13000 foot altitude to avoid overshooting it.PF has to be totally engaged with what the jet's doing at all times. I could have probably detected the overly aggressive descent sooner if I hadn't been worrying about getting down-track speed restrictions put back in.using a lower mode of automation (bow tie) and leaving the speed restrictions in place just in case they're reinstated will reduce the heads down workload of the PF who would then be better able to detect deviations faster.ATC needs to be aware that we can't slow down/descend on a dime and/or make altitude and airspeed restrictions if they drive us in too close before issuing the instruction.
Original NASA ASRS Text
Title: MD-11 Captain reported difficulty complying with multiple short-notice clearance changes on arrival into PHX.
Narrative: Captain was PF (Pilot Flying). We were approaching ZUNI for the EAGUL 6 RNAV STAR into PHX and were subsequently cleared direct to HOMRR intersection and cleared to descend via the EAGUL 6. Approaching FL200 we were handed off to Phoenix Approach who directed us to delete the speed restrictions. The F/O (First Officer) deleted the five speed restrictions in front of us on the arrival. The aircraft had just adjusted the profile for roughly 300 KIAS when we were told to comply with the speed restrictions. We were 4-5 NM from HOMRR with a restriction of 250/17000 feet. I bow-tied the speed and applied full spoilers while the F/O went back to reinserting the remaining four speeds. We made the altitude restriction at 17000 feet but were roughly 20 kts fast as we crossed HOMRR. As soon as the FMS sequenced HOMRR the autopilot commanded an aggressive descent of 5500-6000 feet/minute. The next waypoint was BOHTX with an altitude restriction of 13000-14000 feet. As soon as I recognized the descent I reverted to V/S and commanded a level off. We overshot the 13000 foot restriction by about 300 feet one mile short of BOHTX. After BOHTX we continued the arrival without any further problems. ATC did not say anything about either the airspeed or altitude deviation.Being cleared to descend at a higher than normal speed; then being told to meet speed restrictions in close to the first waypoint put us behind to the point that we couldn't make both the airspeed and altitude restrictions. I felt the altitude was more important at that time and did the best I could with the speed. I don't know why PROF (Profile) commanded such an aggressive descent; but by the time I caught it we were too close to the 13000 foot altitude to avoid overshooting it.PF has to be totally engaged with what the jet's doing at all times. I could have probably detected the overly aggressive descent sooner if I hadn't been worrying about getting down-track speed restrictions put back in.Using a lower mode of automation (bow tie) and leaving the speed restrictions in place just in case they're reinstated will reduce the heads down workload of the PF who would then be better able to detect deviations faster.ATC needs to be aware that we can't slow down/descend on a dime and/or make altitude and airspeed restrictions if they drive us in too close before issuing the instruction.
Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.