Corporate jet flight crew confused by clearance and not sure of GPS approach procedures.

Attributes
ACN	293390
Time
Date	199501
Day	Wed
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : hee
State Reference	AR
Altitude	msl bound lower : 1020 msl bound upper : 2000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme tower : dtw
Operator	general aviation : corporate
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Navigation In Use	Other Other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi pilot : commercial
Experience	flight time last 90 days : 90 flight time total : 4626 flight time type : 223
ASRS Report	293390
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

Inbound for hee 175 degree radial, same as inbound course for the hee NDB or GPS runway 17. We were established on course. Descent clearance from ZME 'descend to 2000 ft and cleared to the airport.' at 10 mi from hee (using FMS) we started our descent to MDA 1020 ft MSL. Became VFR approximately 1700 ft MSL continued inbound to hee. ZME called the airport 12 O'clock, and 6 mi, said nothing about our altitude. We canceled IFR. Our descent below our altitude clearance, was from a lack of communication on our part with center.

Original NASA ASRS Text

Title: CORPORATE JET FLC CONFUSED BY CLRNC AND NOT SURE OF GPS APCH PROCS.

Narrative: INBOUND FOR HEE 175 DEG RADIAL, SAME AS INBOUND COURSE FOR THE HEE NDB OR GPS RWY 17. WE WERE ESTABLISHED ON COURSE. DSCNT CLRNC FROM ZME 'DSND TO 2000 FT AND CLRED TO THE ARPT.' AT 10 MI FROM HEE (USING FMS) WE STARTED OUR DSCNT TO MDA 1020 FT MSL. BECAME VFR APPROX 1700 FT MSL CONTINUED INBOUND TO HEE. ZME CALLED THE ARPT 12 O'CLOCK, AND 6 MI, SAID NOTHING ABOUT OUR ALT. WE CANCELED IFR. OUR DSCNT BELOW OUR ALT CLRNC, WAS FROM A LACK OF COM ON OUR PART WITH CTR.

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.