While on an IFR clearance, pilot descended below assigned altitude. Altitude deviation.

Attributes
ACN	317706
Time
Date	199510
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : det
State Reference	MI
Altitude	msl bound lower : 2700 msl bound upper : 3000
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dtw
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent : approach descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 150 flight time total : 1750 flight time type : 200
ASRS Report	317706
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	non adherence : far non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I took off out of ann arbor to detroit city airport with the intentions of flying VFR. Conditions at ann arbor were less than WX forecasts implied, so I picked up an IFR clearance with detroit metropolitan approach. Approach was somewhat busy with aircraft going into detroit city, so I was vectored through the approach course to ILS runway 33 (which I was informed would happen). I was then turned back toward the course and vectored through again and finally turned for the intercept. I was cleared to descend to 3000 ft and maintain that altitude to gomac. As I leveled at 3000 ft, I saw an aircraft (big) below me to the right and an airport to the left. I was a little concerned with the vectors I had received and when I broke out and saw an aircraft to my right, it was somewhat alarming, so I turned away from the course of the aircraft and descended farther below the cloud deck. I descended about 300 ft, when the controller in a very excited voice called the traffic out and ordered me to climb now! At this point, I was starting to really question ATC and their intentions. The last thing I really wanted to do was climb back into the clouds. The voice was so excited I thought there was some serious question. I was sent back to the detroit approach frequency, and I told them I had the airport. After a verbal lashing, they told me it was windsor, not city and then proceeded to vector me on course and the rest of the trip was uneventful. The controller and I spoke on the phone and discussed the issue.

Original NASA ASRS Text

Title: WHILE ON AN IFR CLRNC, PLT DSNDED BELOW ASSIGNED ALT. ALTDEV.

Narrative: I TOOK OFF OUT OF ANN ARBOR TO DETROIT CITY ARPT WITH THE INTENTIONS OF FLYING VFR. CONDITIONS AT ANN ARBOR WERE LESS THAN WX FORECASTS IMPLIED, SO I PICKED UP AN IFR CLRNC WITH DETROIT METROPOLITAN APCH. APCH WAS SOMEWHAT BUSY WITH ACFT GOING INTO DETROIT CITY, SO I WAS VECTORED THROUGH THE APCH COURSE TO ILS RWY 33 (WHICH I WAS INFORMED WOULD HAPPEN). I WAS THEN TURNED BACK TOWARD THE COURSE AND VECTORED THROUGH AGAIN AND FINALLY TURNED FOR THE INTERCEPT. I WAS CLRED TO DSND TO 3000 FT AND MAINTAIN THAT ALT TO GOMAC. AS I LEVELED AT 3000 FT, I SAW AN ACFT (BIG) BELOW ME TO THE R AND AN ARPT TO THE L. I WAS A LITTLE CONCERNED WITH THE VECTORS I HAD RECEIVED AND WHEN I BROKE OUT AND SAW AN ACFT TO MY R, IT WAS SOMEWHAT ALARMING, SO I TURNED AWAY FROM THE COURSE OF THE ACFT AND DSNDED FARTHER BELOW THE CLOUD DECK. I DSNDED ABOUT 300 FT, WHEN THE CTLR IN A VERY EXCITED VOICE CALLED THE TFC OUT AND ORDERED ME TO CLB NOW! AT THIS POINT, I WAS STARTING TO REALLY QUESTION ATC AND THEIR INTENTIONS. THE LAST THING I REALLY WANTED TO DO WAS CLB BACK INTO THE CLOUDS. THE VOICE WAS SO EXCITED I THOUGHT THERE WAS SOME SERIOUS QUESTION. I WAS SENT BACK TO THE DETROIT APCH FREQ, AND I TOLD THEM I HAD THE ARPT. AFTER A VERBAL LASHING, THEY TOLD ME IT WAS WINDSOR, NOT CITY AND THEN PROCEEDED TO VECTOR ME ON COURSE AND THE REST OF THE TRIP WAS UNEVENTFUL. THE CTLR AND I SPOKE ON THE PHONE AND DISCUSSED THE ISSUE.

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.