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Altitude deviation altitude overshot. Air carrier crew receives a descent clearance while still in the climb and the captain resets the altitude alerter to the lower altitude canceling the altitude capture feature of the autoplt causing an overshoot in altitude.
| Attributes | |
| ACN | 310970 |
| Time | |
| Date | 199507 |
| Day | Fri |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | atc facility : rqz |
| State Reference | AL |
| Altitude | msl bound lower : 22000 msl bound upper : 22400 |
| Environment | |
| Flight Conditions | Mixed |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | artcc : zme |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 5000 flight time type : 2500 |
| ASRS Report | 310970 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp pilot : commercial |
| Experience | flight time last 90 days : 180 flight time total : 16000 flight time type : 3000 |
| ASRS Report | 311083 |
| Events | |
| Anomaly | altitude deviation : overshoot altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
| Resolutory Action | flight crew : returned to intended course or assigned course other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Assigned FL220, pilot's discretion to 11000 ft. The captain asked me to verify some information with the lead flight attendant via the interphone. While I was 'head down' on radio panel (and off the ATC radio), ATC cleared us to descend. As I finished my assigned task and looked up, I noticed we were climbing. I questioned the captain, who said no, we're not supposed to climb. He then descended. We got about 400 ft higher than assigned altitude. He was apparently working on a headset problem when the aircraft started to climb. Supplemental information from acn 311083: while in climb to FL220, prior to leveloff, center issued clearance at pilot's discretion to 11000 ft. The autoplt was engaged and in vertical speed mode. Setting 11000 ft disabled the automatic leveloff at FL220. I think low blood sugar played a big part. The schedule of short legs and no place or time to eat produced a situation where the captain had not eaten in almost 12 hours. Plus the long duty day produced fatigue. A 1 hour plus mechanical delay earlier did not help. No crew meals are carried on the aircraft at this airline. I was just plain out of it, and the symptoms were insidious. The center made no mention of the altitude bust, and there were no other aircraft in the area. Fortunately the first officer had eaten the only left over meal earlier or we might still be climbing!
Original NASA ASRS Text
Title: ALTDEV ALT OVERSHOT. ACR CREW RECEIVES A DSCNT CLRNC WHILE STILL IN THE CLB AND THE CAPT RESETS THE ALT ALERTER TO THE LOWER ALT CANCELING THE ALT CAPTURE FEATURE OF THE AUTOPLT CAUSING AN OVERSHOOT IN ALT.
Narrative: ASSIGNED FL220, PLT'S DISCRETION TO 11000 FT. THE CAPT ASKED ME TO VERIFY SOME INFO WITH THE LEAD FLT ATTENDANT VIA THE INTERPHONE. WHILE I WAS 'HEAD DOWN' ON RADIO PANEL (AND OFF THE ATC RADIO), ATC CLRED US TO DSND. AS I FINISHED MY ASSIGNED TASK AND LOOKED UP, I NOTICED WE WERE CLBING. I QUESTIONED THE CAPT, WHO SAID NO, WE'RE NOT SUPPOSED TO CLB. HE THEN DSNDED. WE GOT ABOUT 400 FT HIGHER THAN ASSIGNED ALT. HE WAS APPARENTLY WORKING ON A HEADSET PROB WHEN THE ACFT STARTED TO CLB. SUPPLEMENTAL INFO FROM ACN 311083: WHILE IN CLB TO FL220, PRIOR TO LEVELOFF, CTR ISSUED CLRNC AT PLT'S DISCRETION TO 11000 FT. THE AUTOPLT WAS ENGAGED AND IN VERT SPD MODE. SETTING 11000 FT DISABLED THE AUTO LEVELOFF AT FL220. I THINK LOW BLOOD SUGAR PLAYED A BIG PART. THE SCHEDULE OF SHORT LEGS AND NO PLACE OR TIME TO EAT PRODUCED A SIT WHERE THE CAPT HAD NOT EATEN IN ALMOST 12 HRS. PLUS THE LONG DUTY DAY PRODUCED FATIGUE. A 1 HR PLUS MECHANICAL DELAY EARLIER DID NOT HELP. NO CREW MEALS ARE CARRIED ON THE ACFT AT THIS AIRLINE. I WAS JUST PLAIN OUT OF IT, AND THE SYMPTOMS WERE INSIDIOUS. THE CTR MADE NO MENTION OF THE ALT BUST, AND THERE WERE NO OTHER ACFT IN THE AREA. FORTUNATELY THE FO HAD EATEN THE ONLY LEFT OVER MEAL EARLIER OR WE MIGHT STILL BE CLBING!
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.