Altitude deviation. Overshoot in climb.

Attributes
ACN	126842
Time
Date	198910
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : txk
State Reference	AR
Altitude	msl bound lower : 33000 msl bound upper : 33300
Aircraft 1
Controlling Facilities	artcc : zfw tower : bwi
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 250 flight time total : 12000 flight time type : 600
ASRS Report	126842
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : clearance other anomaly
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were climbing with the intention of leveling at FL330. Captain was manually flying the aircraft with the FMS selected to mach and autothrottle selected to EPR limit (climb EPR limit). Altitude (FL330 in FMS) was armed. Captain manually leveled at FL330 then switched on the autoplt. He then looked into his kit bag for something. The autoplt stayed in mach and the autothrottles remained in EPR limit. I stated, 'you're still in mach.' he then commanded the autothrottles to mach select .760, however the autothrottles had already sped the aircraft to .780+. The FMS was still in mach (.760) and the aircraft did not capture or hold altitude. Therefore, the aircraft started to climb rapidly to maintain the commanded mach .760 instead of the existing mach .780+. At 33100' I said, 'watch your altitude.' I repeated this alert against 33200'. I was reaching for the control yoke when he clicked off the autoplt and recovered to our assigned altitude. He did not really understand what had happened. Perceptions: know how the system works; pay attention to the autoplt, especially when leveling at altitudes.

Original NASA ASRS Text

Title: ALT DEVIATION. OVERSHOOT IN CLIMB.

Narrative: WE WERE CLBING WITH THE INTENTION OF LEVELING AT FL330. CAPT WAS MANUALLY FLYING THE ACFT WITH THE FMS SELECTED TO MACH AND AUTOTHROTTLE SELECTED TO EPR LIMIT (CLB EPR LIMIT). ALT (FL330 IN FMS) WAS ARMED. CAPT MANUALLY LEVELED AT FL330 THEN SWITCHED ON THE AUTOPLT. HE THEN LOOKED INTO HIS KIT BAG FOR SOMETHING. THE AUTOPLT STAYED IN MACH AND THE AUTOTHROTTLES REMAINED IN EPR LIMIT. I STATED, 'YOU'RE STILL IN MACH.' HE THEN COMMANDED THE AUTOTHROTTLES TO MACH SELECT .760, HOWEVER THE AUTOTHROTTLES HAD ALREADY SPED THE ACFT TO .780+. THE FMS WAS STILL IN MACH (.760) AND THE ACFT DID NOT CAPTURE OR HOLD ALT. THEREFORE, THE ACFT STARTED TO CLB RAPIDLY TO MAINTAIN THE COMMANDED MACH .760 INSTEAD OF THE EXISTING MACH .780+. AT 33100' I SAID, 'WATCH YOUR ALT.' I REPEATED THIS ALERT AGAINST 33200'. I WAS REACHING FOR THE CTL YOKE WHEN HE CLICKED OFF THE AUTOPLT AND RECOVERED TO OUR ASSIGNED ALT. HE DID NOT REALLY UNDERSTAND WHAT HAD HAPPENED. PERCEPTIONS: KNOW HOW THE SYS WORKS; PAY ATTN TO THE AUTOPLT, ESPECIALLY WHEN LEVELING AT ALTS.

Data retrieved from NASA's ASRS site as of August 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.