E120 captain descended below published minimum altitude on approach.

Attributes
ACN	421768
Time
Date	199811
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : iubr airport : san
State Reference	CA
Altitude	msl bound lower : 1800 msl bound upper : 2000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Brasilia EMB-120 All Series
Operating Under FAR Part	Part 121
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : cfi
Experience	flight time last 90 days : 250 flight time total : 2900 flight time type : 600
ASRS Report	421768
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : far other anomaly other
Independent Detector	other controllera other flight crewa
Consequence	Other
Supplementary
Air Traffic Incident	Pilot Deviation

Narrative:

Socal approach vectored us onto the iubr localizer at san inside of swatt (D12.6) and told us to maintain 2100 ft until established and cleared us for the localizer runway 27 approach. We established on the localizer and descended to the minimum altitude of 2000 ft until reebo. At about 8 DME, I looked down at my approach chart to confirm the distance of reebo (6.4). As I looked up, I saw we were descending through 1800 ft at 1000 FPM and the DME read 7.8. I immediately told the captain, who was hand flying, 'we're still at 2000 ft here.' he mumbled, 'oh, oh yeah...' as lindberg tower told us 'altitude alert, you have a minimum altitude of 2000 ft there.' I rogered that and the captain corrected his altitude. The remainder of the approach was completed uneventfully. This particular captain is notorious for stunts like this but is very senior and few first officer's will say anything, but I did anyway. I don't know of any factors contributing to this event except for the captain's incompetence. If a crew member can't look away for 2/10 of a mi without the other pilot doing something stupid, there's a problem. Perhaps he was tired. I asked him about it and he shrugged it off. His attitude is what scared me.

Original NASA ASRS Text

Title: E120 CAPT DSNDED BELOW PUBLISHED MINIMUM ALT ON APCH.

Narrative: SOCAL APCH VECTORED US ONTO THE IUBR LOC AT SAN INSIDE OF SWATT (D12.6) AND TOLD US TO MAINTAIN 2100 FT UNTIL ESTABLISHED AND CLRED US FOR THE LOC RWY 27 APCH. WE ESTABLISHED ON THE LOC AND DSNDED TO THE MINIMUM ALT OF 2000 FT UNTIL REEBO. AT ABOUT 8 DME, I LOOKED DOWN AT MY APCH CHART TO CONFIRM THE DISTANCE OF REEBO (6.4). AS I LOOKED UP, I SAW WE WERE DSNDING THROUGH 1800 FT AT 1000 FPM AND THE DME READ 7.8. I IMMEDIATELY TOLD THE CAPT, WHO WAS HAND FLYING, 'WE'RE STILL AT 2000 FT HERE.' HE MUMBLED, 'OH, OH YEAH...' AS LINDBERG TWR TOLD US 'ALT ALERT, YOU HAVE A MINIMUM ALT OF 2000 FT THERE.' I ROGERED THAT AND THE CAPT CORRECTED HIS ALT. THE REMAINDER OF THE APCH WAS COMPLETED UNEVENTFULLY. THIS PARTICULAR CAPT IS NOTORIOUS FOR STUNTS LIKE THIS BUT IS VERY SENIOR AND FEW FO'S WILL SAY ANYTHING, BUT I DID ANYWAY. I DON'T KNOW OF ANY FACTORS CONTRIBUTING TO THIS EVENT EXCEPT FOR THE CAPT'S INCOMPETENCE. IF A CREW MEMBER CAN'T LOOK AWAY FOR 2/10 OF A MI WITHOUT THE OTHER PLT DOING SOMETHING STUPID, THERE'S A PROB. PERHAPS HE WAS TIRED. I ASKED HIM ABOUT IT AND HE SHRUGGED IT OFF. HIS ATTITUDE IS WHAT SCARED ME.

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.