Descent below minimums. Unauthorized NAVAID use.

Attributes
ACN	292899
Time
Date	199412
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sgj
State Reference	FL
Altitude	msl bound lower : 400 msl bound upper : 400
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : jax
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 25 flight time total : 600 flight time type : 540
ASRS Report	292899
Events
Anomaly	non adherence : clearance non adherence : far non adherence : published procedure
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was making a VOR approach to runway 31 at sgj. AWOS reported 400 ft indefinite MDA is 400 ft with local altitude at 2.3 DME. I had local altimeter but was using a noncertified GPS for distance and did not notice that sgj DME was not functioning. No NOTAM was received from either duat or voice briefing to alert me. I knew of the MDA of 460 ft with DME out but not recognizing the DME OTS, descended to 400 ft. Just prior to that altitude, I broke out and made a normal landing. Even though I knew the 2.3 distance, I should have monitored DME. In fact, it should have been primary. My experience with the GPS has been so good with unbelievable accuracy that I have come to rely on it as my primary navigation instrument. I will have to change that. I do feel that the FAA needs to recognize this accuracy and certify many more units for en route and terminal IFR.

Original NASA ASRS Text

Title: DSCNT BELOW MINIMUMS. UNAUTH NAVAID USE.

Narrative: I WAS MAKING A VOR APCH TO RWY 31 AT SGJ. AWOS RPTED 400 FT INDEFINITE MDA IS 400 FT WITH LCL ALT AT 2.3 DME. I HAD LCL ALTIMETER BUT WAS USING A NONCERTIFIED GPS FOR DISTANCE AND DID NOT NOTICE THAT SGJ DME WAS NOT FUNCTIONING. NO NOTAM WAS RECEIVED FROM EITHER DUAT OR VOICE BRIEFING TO ALERT ME. I KNEW OF THE MDA OF 460 FT WITH DME OUT BUT NOT RECOGNIZING THE DME OTS, DSNDED TO 400 FT. JUST PRIOR TO THAT ALT, I BROKE OUT AND MADE A NORMAL LNDG. EVEN THOUGH I KNEW THE 2.3 DISTANCE, I SHOULD HAVE MONITORED DME. IN FACT, IT SHOULD HAVE BEEN PRIMARY. MY EXPERIENCE WITH THE GPS HAS BEEN SO GOOD WITH UNBELIEVABLE ACCURACY THAT I HAVE COME TO RELY ON IT AS MY PRIMARY NAV INST. I WILL HAVE TO CHANGE THAT. I DO FEEL THAT THE FAA NEEDS TO RECOGNIZE THIS ACCURACY AND CERTIFY MANY MORE UNITS FOR ENRTE AND TERMINAL IFR.

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.