Charter pilot engages autoplt but aircraft climbs. Altitude deviation.

Attributes
ACN	338270
Time
Date	199606
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : bdl
State Reference	CT
Altitude	msl bound lower : 7000 msl bound upper : 7400
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : bdl
Operator	other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 60 flight time total : 1800 flight time type : 25
ASRS Report	338270
Events
Anomaly	altitude deviation : overshoot non adherence : far non adherence : clearance
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:

After trimming the aircraft for cruise I placed the autoplt on and saw that it was trimmed. I believe the airspeed was probably still building and once it gained a little more speed it started to climb.

Original NASA ASRS Text

Title: CHARTER PLT ENGAGES AUTOPLT BUT ACFT CLBS. ALTDEV.

Narrative: AFTER TRIMMING THE ACFT FOR CRUISE I PLACED THE AUTOPLT ON AND SAW THAT IT WAS TRIMMED. I BELIEVE THE AIRSPD WAS PROBABLY STILL BUILDING AND ONCE IT GAINED A LITTLE MORE SPD IT STARTED TO CLB.

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.