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An A320 flight crew; distracted by VNAV systems training; fail to make a crossing restriction on descent into ord.
| Attributes | |
| ACN | 858640 |
| Time | |
| Date | 200911 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | ORD.Airport |
| State Reference | IL |
| Aircraft 1 | |
| Make Model Name | A320 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Descent |
| Route In Use | STAR WATSN1 |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | FMS/FMC |
| Person 1 | |
| Function | First Officer Pilot Not Flying |
| Experience | Flight Crew Last 90 Days 100 Flight Crew Total 10500 Flight Crew Type 612 |
| Events | |
| Anomaly | Aircraft Equipment Problem Less Severe Deviation - Altitude Crossing Restriction Not Met Deviation - Procedural Clearance |
Narrative:
While in the descent for ord the captain was giving me a briefing on the VNAV descent function of the airbus as this was my first leg back in the airbus after many years flying boeing. We were discussing the 'doughnut'; managed vs selected speeds and various other items. During this time the 'doughnut' indicated at our speed we would be level at watsn intersection at 12000ft as planned and assigned. During this time we were not backing the airbus up with a 3-1 calculation due in large part to our ongoing discussion. When about 3-4 miles from watsn the circle around the waypoint went to amber and I inquired as to why that would happen as we were still on the 'doughnut' and then we both looked at the doughnut and saw we were now high. The captain extended the speed brakes minimizing the amount we were off from our altitude but we still ended up over the fix about 700ft high. I have heard people say you cant trust the VNAV function at all in an airbus and I guess years on boeing equipment led me to be complacent on my 3-1 calculations as I have never had this happen on a boeing. I will be much more vigilant now that I am back on the airbus.
Original NASA ASRS Text
Title: An A320 flight crew; distracted by VNAV systems training; fail to make a crossing restriction on descent into ORD.
Narrative: While in the descent for ORD the Captain was giving me a briefing on the VNAV descent function of the Airbus as this was my first leg back in the Airbus after many years flying Boeing. We were discussing the 'doughnut'; managed vs selected speeds and various other items. During this time the 'doughnut' indicated at our speed we would be level at WATSN intersection at 12000ft as planned and assigned. During this time we were not backing the Airbus up with a 3-1 calculation due in large part to our ongoing discussion. When about 3-4 miles from WATSN the circle around the waypoint went to amber and I inquired as to why that would happen as we were still on the 'doughnut' and then we both looked at the doughnut and saw we were now high. The Captain extended the speed brakes minimizing the amount we were off from our altitude but we still ended up over the fix about 700ft high. I have heard people say you cant trust the VNAV function at all in an Airbus and I guess years on Boeing equipment led me to be complacent on my 3-1 calculations as I have never had this happen on a Boeing. I will be much more vigilant now that I am back on the Airbus.
Data retrieved from NASA's ASRS site as of April 2012 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.