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A cpr twin jet first officer overshoots his assigned altitude when attempting a speed change using the flight director command bars northeast of bro, tx.
| Attributes | |
| ACN | 470610 |
| Time | |
| Date | 200004 |
| Day | Tue |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| State Reference | TX |
| Altitude | msl bound lower : 9000 msl bound upper : 9600 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | general aviation : corporate |
| Make Model Name | Medium Transport, Low Wing, 2 Turbojet Eng |
| Operating Under FAR Part | Part 91 |
| Navigation In Use | other |
| Flight Phase | climbout : intermediate altitude |
| Route In Use | departure : on vectors enroute airway : ns.airway |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : corporate |
| Function | flight crew : first officer |
| Qualification | pilot : multi engine pilot : commercial pilot : cfi pilot : atp pilot : instrument |
| Experience | flight time last 90 days : 250 flight time total : 15250 flight time type : 250 |
| ASRS Report | 470610 |
| Person 2 | |
| Affiliation | company : corporate |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | altitude deviation : overshoot non adherence : clearance other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : returned to assigned altitude |
| Consequence | Other |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Airspace Structure Aircraft ATC Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Departing bro, ATC instructed 'cancel speed restr.' we had not been given a speed restr, so we asked ATC if we had been given one. ATC advised us of a special test program, whereby aircraft operating below 10000 ft MSL were able to operate at greater than 250 KTS if cleared by ATC. At the time of the clearance, we were climbing to 9000 ft assigned at 250 KTS using a preset climb schedule in the FMS. I attempted to increase speed of aircraft by lowering nose, but because of the preset speeds in FMS the command bars on the pilots ADI commanded an increase climb pitch to bring down the airspeed. Instinctively I brought the nose back up to match the command bars. At about the same time I matched pitch with command bars, they suddenly dropped. Because the altitude select feature was tripped on by rapidly approaching our assigned altitude of 9000 ft, I was unable to match the new position of the command bars because of excessive negative 'G' loads. By the time I had completed the recovery maneuver, the aircraft had gone through the assigned altitude by 600 ft (9600 ft). We returned to our assigned altitude. ATC did not seem to notice.
Original NASA ASRS Text
Title: A CPR TWIN JET FO OVERSHOOTS HIS ASSIGNED ALT WHEN ATTEMPTING A SPD CHANGE USING THE FLT DIRECTOR COMMAND BARS NE OF BRO, TX.
Narrative: DEPARTING BRO, ATC INSTRUCTED 'CANCEL SPD RESTR.' WE HAD NOT BEEN GIVEN A SPD RESTR, SO WE ASKED ATC IF WE HAD BEEN GIVEN ONE. ATC ADVISED US OF A SPECIAL TEST PROGRAM, WHEREBY ACFT OPERATING BELOW 10000 FT MSL WERE ABLE TO OPERATE AT GREATER THAN 250 KTS IF CLRED BY ATC. AT THE TIME OF THE CLRNC, WE WERE CLBING TO 9000 FT ASSIGNED AT 250 KTS USING A PRESET CLB SCHEDULE IN THE FMS. I ATTEMPTED TO INCREASE SPD OF ACFT BY LOWERING NOSE, BUT BECAUSE OF THE PRESET SPDS IN FMS THE COMMAND BARS ON THE PLTS ADI COMMANDED AN INCREASE CLB PITCH TO BRING DOWN THE AIRSPD. INSTINCTIVELY I BROUGHT THE NOSE BACK UP TO MATCH THE COMMAND BARS. AT ABOUT THE SAME TIME I MATCHED PITCH WITH COMMAND BARS, THEY SUDDENLY DROPPED. BECAUSE THE ALT SELECT FEATURE WAS TRIPPED ON BY RAPIDLY APCHING OUR ASSIGNED ALT OF 9000 FT, I WAS UNABLE TO MATCH THE NEW POS OF THE COMMAND BARS BECAUSE OF EXCESSIVE NEGATIVE 'G' LOADS. BY THE TIME I HAD COMPLETED THE RECOVERY MANEUVER, THE ACFT HAD GONE THROUGH THE ASSIGNED ALT BY 600 FT (9600 FT). WE RETURNED TO OUR ASSIGNED ALT. ATC DID NOT SEEM TO NOTICE.
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.