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An air carrier flight crew climbed through their assigned altitude while performing a noise abatement departure.
| Attributes | |
| ACN | 328120 |
| Time | |
| Date | 199602 |
| Day | Sun |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : sna |
| State Reference | CA |
| Altitude | msl bound lower : 5000 msl bound upper : 7500 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : sna |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | climbout : intermediate altitude |
| Route In Use | departure : noise abatement departure sid : sid |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 200 flight time total : 9000 flight time type : 3500 |
| ASRS Report | 328120 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | altitude deviation : overshoot non adherence : clearance non adherence : far |
| Independent Detector | other flight crewa |
| Resolutory Action | controller : issued new clearance other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Aircraft was initially cleared for takeoff, and to climb and maintain 5000 ft. Crew was extremely busy performing the very difficult and in my opinion dangerous special procedure from the orange county airport. It requires extensive nonstandard vertical and lateral maneuvers in order to comply with local noise abatement policy. After completing most of these maneuvers, I (copilot) noticed the captain was climbing through 7500 ft. I looked at the altitude window on the MCP and discovered it was now set to read 10000 ft. After questioning the captain if we had been cleared to the higher altitude, he said no, not as far as he knew. He quickly leveled the aircraft off at approximately 7500 ft, and I called the tower (or departure control) and asked them if we were cleared to 10000 ft. He responded by saying, 'you are cleared to 10000 ft.' there was no conflict with any other aircraft in the area, but this matter was still very unsettling to both of us. After much discussion later, we believe we have discovered the culprit. After airspeed and altitude have been set initially on the forward panel (MCP), any type of power (electrical) interruption will cause both these 'windows' to default to 100 KTS and 10000 ft. We had such an interruption shortly before pushback from the gate. When switching from external power to our own APU power, the captain accidentally disconnected external power from the aircraft before the APU was up and running and ready to take over the job of pwring the aircraft system. When this happened the aircraft was totally unpwred (except for battery) for a few seconds. He quickly reselected external power, and all electrical system were again pwred. What we did not realize is that the airspeed and altitude 'windows' had defaulted to 100 KTS and 10000 ft. The airspeed mistake was caught on taxi out (via checklist), but the altitude apparently was not. If we both had not been so extremely occupied with performing this ridiculous special takeoff procedure, I'm certain we both would have caught it!
Original NASA ASRS Text
Title: AN ACR FLC CLBED THROUGH THEIR ASSIGNED ALT WHILE PERFORMING A NOISE ABATEMENT DEP.
Narrative: ACFT WAS INITIALLY CLRED FOR TKOF, AND TO CLB AND MAINTAIN 5000 FT. CREW WAS EXTREMELY BUSY PERFORMING THE VERY DIFFICULT AND IN MY OPINION DANGEROUS SPECIAL PROC FROM THE ORANGE COUNTY ARPT. IT REQUIRES EXTENSIVE NONSTANDARD VERT AND LATERAL MANEUVERS IN ORDER TO COMPLY WITH LCL NOISE ABATEMENT POLICY. AFTER COMPLETING MOST OF THESE MANEUVERS, I (COPLT) NOTICED THE CAPT WAS CLBING THROUGH 7500 FT. I LOOKED AT THE ALT WINDOW ON THE MCP AND DISCOVERED IT WAS NOW SET TO READ 10000 FT. AFTER QUESTIONING THE CAPT IF WE HAD BEEN CLRED TO THE HIGHER ALT, HE SAID NO, NOT AS FAR AS HE KNEW. HE QUICKLY LEVELED THE ACFT OFF AT APPROX 7500 FT, AND I CALLED THE TWR (OR DEP CTL) AND ASKED THEM IF WE WERE CLRED TO 10000 FT. HE RESPONDED BY SAYING, 'YOU ARE CLRED TO 10000 FT.' THERE WAS NO CONFLICT WITH ANY OTHER ACFT IN THE AREA, BUT THIS MATTER WAS STILL VERY UNSETTLING TO BOTH OF US. AFTER MUCH DISCUSSION LATER, WE BELIEVE WE HAVE DISCOVERED THE CULPRIT. AFTER AIRSPD AND ALT HAVE BEEN SET INITIALLY ON THE FORWARD PANEL (MCP), ANY TYPE OF PWR (ELECTRICAL) INTERRUPTION WILL CAUSE BOTH THESE 'WINDOWS' TO DEFAULT TO 100 KTS AND 10000 FT. WE HAD SUCH AN INTERRUPTION SHORTLY BEFORE PUSHBACK FROM THE GATE. WHEN SWITCHING FROM EXTERNAL PWR TO OUR OWN APU PWR, THE CAPT ACCIDENTALLY DISCONNECTED EXTERNAL PWR FROM THE ACFT BEFORE THE APU WAS UP AND RUNNING AND READY TO TAKE OVER THE JOB OF PWRING THE ACFT SYS. WHEN THIS HAPPENED THE ACFT WAS TOTALLY UNPWRED (EXCEPT FOR BATTERY) FOR A FEW SECONDS. HE QUICKLY RESELECTED EXTERNAL PWR, AND ALL ELECTRICAL SYS WERE AGAIN PWRED. WHAT WE DID NOT REALIZE IS THAT THE AIRSPD AND ALT 'WINDOWS' HAD DEFAULTED TO 100 KTS AND 10000 FT. THE AIRSPD MISTAKE WAS CAUGHT ON TAXI OUT (VIA CHKLIST), BUT THE ALT APPARENTLY WAS NOT. IF WE BOTH HAD NOT BEEN SO EXTREMELY OCCUPIED WITH PERFORMING THIS RIDICULOUS SPECIAL TKOF PROC, I'M CERTAIN WE BOTH WOULD HAVE CAUGHT IT!
Data retrieved from NASA's ASRS site as of July 2007 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.