Altitude deviation on climb. Overshoot in light aircraft, high climb rate. Autoplt couldn't keep up.

Attributes
ACN	339300
Time
Date	199606
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : orl airport : mco
State Reference	FL
Altitude	msl bound lower : 5000 msl bound upper : 5500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mco
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 115 flight time total : 15000 flight time type : 4700
ASRS Report	339300
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 9000 flight time type : 3500
ASRS Report	338966
Events
Anomaly	altitude deviation : overshoot non adherence : clearance
Independent Detector	other flight crewa other other : unspecified cockpit
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:

On a ferry flight from mco to mlb flight took off light and on climb out engaged autoplt with IAS hold to a clearance altitude of 5000 ft MSL. The aircraft was very light and somehow passed through 5000 ft. I disconnected autoplt and started nose over back down to 5000 ft, shot over 400-500 ft 5400 ft to 5500 ft and immediately descended back to 5000 ft MSL. No traffic in area was noted. Somehow altitude armed became unarmed during climb. Recommend closer monitoring of autoplt altitude capture especially during high rates of climb in very light aircraft conditions. Supplemental information from acn 338966: due to the fact the flight was so short I (as PNF) was already doing preliminary approach phase duties during climb out. No mention was made by ATC of incident. Possible scenario: autoplt on during capture mode, vertical speed wheel touched inadvertently after capture mode, more caution used on short flts to not disregard altitude callouts, and wait till level flight to do other work.

Original NASA ASRS Text

Title: ALTDEV ON CLB. OVERSHOOT IN LIGHT ACFT, HIGH CLB RATE. AUTOPLT COULDN'T KEEP UP.

Narrative: ON A FERRY FLT FROM MCO TO MLB FLT TOOK OFF LIGHT AND ON CLBOUT ENGAGED AUTOPLT WITH IAS HOLD TO A CLRNC ALT OF 5000 FT MSL. THE ACFT WAS VERY LIGHT AND SOMEHOW PASSED THROUGH 5000 FT. I DISCONNECTED AUTOPLT AND STARTED NOSE OVER BACK DOWN TO 5000 FT, SHOT OVER 400-500 FT 5400 FT TO 5500 FT AND IMMEDIATELY DSNDED BACK TO 5000 FT MSL. NO TFC IN AREA WAS NOTED. SOMEHOW ALT ARMED BECAME UNARMED DURING CLB. RECOMMEND CLOSER MONITORING OF AUTOPLT ALT CAPTURE ESPECIALLY DURING HIGH RATES OF CLB IN VERY LIGHT ACFT CONDITIONS. SUPPLEMENTAL INFO FROM ACN 338966: DUE TO THE FACT THE FLT WAS SO SHORT I (AS PNF) WAS ALREADY DOING PRELIMINARY APCH PHASE DUTIES DURING CLBOUT. NO MENTION WAS MADE BY ATC OF INCIDENT. POSSIBLE SCENARIO: AUTOPLT ON DURING CAPTURE MODE, VERT SPD WHEEL TOUCHED INADVERTENTLY AFTER CAPTURE MODE, MORE CAUTION USED ON SHORT FLTS TO NOT DISREGARD ALT CALLOUTS, AND WAIT TILL LEVEL FLT TO DO OTHER WORK.

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.