MD90 crew flew below authority/authorized minimum altitude on the NDB runway 35 approach at pns.

Attributes
ACN	484460
Time
Date	200009
Day	Wed
Local Time Of Day	0601 To 1200
Place
State Reference	FL
Altitude	msl bound lower : 700 msl bound upper : 1200
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-90 Series (DC-9-90) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other ndb
Flight Phase	descent : intermediate altitude
Route In Use	approach : instrument non precision
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : cfi pilot : flight engineer pilot : instrument pilot : multi engine pilot : atp
Experience	flight time last 90 days : 195 flight time total : 9350 flight time type : 1940
ASRS Report	484460
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : published procedure non adherence : clearance non adherence : company policies other anomaly other other spatial deviation
Independent Detector	atc equipment : msaw other controllera
Resolutory Action	none taken : anomaly accepted
Supplementary
Problem Areas	Flight Crew Human Performance FAA Airport
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While shooting the NDB runway 35 to pns a descent was started early prior to reaching the piere intersection while established on course inbound. This is a complex non precision approach requiring the piere intersection to idented by crosstuning the nyn VOR radial 119 degrees. This intersection was believed to be idented by the PNF so I descended to the next altitude of 700 ft. We were directed to the error after becoming VMC and approximately 5 NM from the airport by the pns tower controller. The approach was continued under VMC with the airport in sight at approximately 1000 ft MSL and an uneventful landing resulted. This situation could have been avoided with a more reliable way of identing the piere intersection, such as being in the FMS database, radar identify, or via a DME reading.

Original NASA ASRS Text

Title: MD90 CREW FLEW BELOW AUTH MINIMUM ALT ON THE NDB RWY 35 APCH AT PNS.

Narrative: WHILE SHOOTING THE NDB RWY 35 TO PNS A DSCNT WAS STARTED EARLY PRIOR TO REACHING THE PIERE INTXN WHILE ESTABLISHED ON COURSE INBOUND. THIS IS A COMPLEX NON PRECISION APCH REQUIRING THE PIERE INTXN TO IDENTED BY CROSSTUNING THE NYN VOR RADIAL 119 DEGS. THIS INTXN WAS BELIEVED TO BE IDENTED BY THE PNF SO I DSNDED TO THE NEXT ALT OF 700 FT. WE WERE DIRECTED TO THE ERROR AFTER BECOMING VMC AND APPROX 5 NM FROM THE ARPT BY THE PNS TWR CTLR. THE APCH WAS CONTINUED UNDER VMC WITH THE ARPT IN SIGHT AT APPROX 1000 FT MSL AND AN UNEVENTFUL LNDG RESULTED. THIS SIT COULD HAVE BEEN AVOIDED WITH A MORE RELIABLE WAY OF IDENTING THE PIERE INTXN, SUCH AS BEING IN THE FMS DATABASE, RADAR IDENT, OR VIA A DME READING.

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.