Narrative:

I was an MD88 first officer; not flying when this event occurred. Approach was entered correctly and displayed on EFIS/navigation system. We received vectors to right base and clearance to fly the runway 3 visual approach following a B737 4 NM ahead. Captain/PF disconnected autoplt at approximately 9000 ft MSL entering right base; aircraft speed and confign under control. Rate of descent entering base approximately 1500 FPM; under control. Entering base; I continued to look outside the aircraft keeping an eye on our interval and the runway (unfamiliar field). As I looked back in; I noticed that the rate of descent had shallowed; but we were still descending at approximately 800 FPM. I scanned aircraft altitude of approximately 6200 ft MSL; just as we were turning right to final in the vicinity of the FAF. (Altitude on GS at 7400 ft MSL.) PF leveled off at about 6000 ft MSL as the aircraft stabilized on final approach heading. ATC issued a 'low altitude alert' message as we rolled out on final. PF decided to maintain level altitude and 'drive to'/intercept the normal GS. Radar altimeter indicated between 700-800 ft AGL until GS intercept at which point we descended and landed normally. The aircraft was below the published FAF altitude as we turned final. Granted; it was a visual approach; but we were low. I was slow to react with a verbal command ('you're low;' 'climb;' 'go around') for a couple of reasons. The first is that I was late xchking the altitude as we turned final. The second reason I hesitated is that I tried to rationalize why the PF (with considerable experience and familiarity with the field) might consider this a normal sight-picture/approach. In order to help prevent this from happening; pilots need to fly visual approachs within parameters that will establish them on normal GS at the FAF. In addition to using/xchking available navigation and approach equipment; pilots should not descend below FAF altitude (or a commensurate altitude if a short approach) until established on final. At a minimum; if pilots are the least bit unfamiliar; at night and/or marginal WX they should ask for vectors to final. What I will do in the future is be more proactive when my 20 yrs of military and commercial flying experience tell me something 'don't look right.'

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Original NASA ASRS Text

Title: AN MD80 FO RPTS HE DID NOT RESPOND APPROPRIATELY WHEN THE CAPT FLEW A VISUAL APCH FINAL VERY LOW AND WAS CALLED BY ATC.

Narrative: I WAS AN MD88 FO; NOT FLYING WHEN THIS EVENT OCCURRED. APCH WAS ENTERED CORRECTLY AND DISPLAYED ON EFIS/NAV SYS. WE RECEIVED VECTORS TO R BASE AND CLRNC TO FLY THE RWY 3 VISUAL APCH FOLLOWING A B737 4 NM AHEAD. CAPT/PF DISCONNECTED AUTOPLT AT APPROX 9000 FT MSL ENTERING R BASE; ACFT SPD AND CONFIGN UNDER CTL. RATE OF DSCNT ENTERING BASE APPROX 1500 FPM; UNDER CTL. ENTERING BASE; I CONTINUED TO LOOK OUTSIDE THE ACFT KEEPING AN EYE ON OUR INTERVAL AND THE RWY (UNFAMILIAR FIELD). AS I LOOKED BACK IN; I NOTICED THAT THE RATE OF DSCNT HAD SHALLOWED; BUT WE WERE STILL DSNDING AT APPROX 800 FPM. I SCANNED ACFT ALT OF APPROX 6200 FT MSL; JUST AS WE WERE TURNING R TO FINAL IN THE VICINITY OF THE FAF. (ALT ON GS AT 7400 FT MSL.) PF LEVELED OFF AT ABOUT 6000 FT MSL AS THE ACFT STABILIZED ON FINAL APCH HEADING. ATC ISSUED A 'LOW ALT ALERT' MESSAGE AS WE ROLLED OUT ON FINAL. PF DECIDED TO MAINTAIN LEVEL ALT AND 'DRIVE TO'/INTERCEPT THE NORMAL GS. RADAR ALTIMETER INDICATED BTWN 700-800 FT AGL UNTIL GS INTERCEPT AT WHICH POINT WE DSNDED AND LANDED NORMALLY. THE ACFT WAS BELOW THE PUBLISHED FAF ALT AS WE TURNED FINAL. GRANTED; IT WAS A VISUAL APCH; BUT WE WERE LOW. I WAS SLOW TO REACT WITH A VERBAL COMMAND ('YOU'RE LOW;' 'CLB;' 'GO AROUND') FOR A COUPLE OF REASONS. THE FIRST IS THAT I WAS LATE XCHKING THE ALT AS WE TURNED FINAL. THE SECOND REASON I HESITATED IS THAT I TRIED TO RATIONALIZE WHY THE PF (WITH CONSIDERABLE EXPERIENCE AND FAMILIARITY WITH THE FIELD) MIGHT CONSIDER THIS A NORMAL SIGHT-PICTURE/APCH. IN ORDER TO HELP PREVENT THIS FROM HAPPENING; PLTS NEED TO FLY VISUAL APCHS WITHIN PARAMETERS THAT WILL ESTABLISH THEM ON NORMAL GS AT THE FAF. IN ADDITION TO USING/XCHKING AVAILABLE NAV AND APCH EQUIP; PLTS SHOULD NOT DSND BELOW FAF ALT (OR A COMMENSURATE ALT IF A SHORT APCH) UNTIL ESTABLISHED ON FINAL. AT A MINIMUM; IF PLTS ARE THE LEAST BIT UNFAMILIAR; AT NIGHT AND/OR MARGINAL WX THEY SHOULD ASK FOR VECTORS TO FINAL. WHAT I WILL DO IN THE FUTURE IS BE MORE PROACTIVE WHEN MY 20 YRS OF MIL AND COMMERCIAL FLYING EXPERIENCE TELL ME SOMETHING 'DON'T LOOK RIGHT.'

Data retrieved from NASA's ASRS site as of January 2009 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.