Private pilot of an small transport twin descended below assigned altitude.

Attributes
ACN	301820
Time
Date	199504
Day	Thu
Place
Locale Reference	airport : gmu
State Reference	SC
Altitude	msl bound lower : 2700 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : gsp tower : lax
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 45 flight time total : 1250 flight time type : 45
ASRS Report	301820
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	altitude deviation : overshoot 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:

While descending into gnw I was cleared to 3000 ft, inadvertently went down to 2700 ft, went back to 3000 ft.

Original NASA ASRS Text

Title: PVT PLT OF AN SMT TWIN DSNDED BELOW ASSIGNED ALT.

Narrative: WHILE DSNDING INTO GNW I WAS CLRED TO 3000 FT, INADVERTENTLY WENT DOWN TO 2700 FT, WENT BACK TO 3000 FT.

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.