Narrative:

ATC was issuing vectors as we approached myr from the nnw. We called the airport in sight, and ATC told us to maintain 1600 ft until established on a straight-in final, cleared visual approach runway 35. We discussed the 1600 ft limitation and 1600 ft was set/confirmed in the altitude preselector/alerter. On mid-field left downwind at 1600 ft with the captain hand-flying, tower cleared us to land runway 35 and repeated the instruction to maintain 1600 ft until on final to avoid banner tow aircraft along the coastline. We acknowledged the clearance and 1600 ft instruction. Our landing weight required use of the 46000 pound v-spd/maneuvering speed card positioned on the aircraft cockpit center pedestal. The minimum maneuvering speed for our flaps 30 degree confign/weight was 161 KIAS. Any turns at less than 161 KTS are restr to 15 degree bank angle. Prior to the captain beginning his downwind-to-base turn, I notified him that our minimum speed was 161 KTS (our IAS was 150 KTS). No correction was made. The captain then entered a full 30 degree bank left turn at 145 KIAS and began to descend from 1600 ft while on base. The altitude alerter sounded as we went 200 ft low but no correction was made. I told the captain we were 300 ft low but again no correction was made and descent continued until we rolled out on final at 800 ft MSL. ATC made no complaints.

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Original NASA ASRS Text

Title: CAPT OF CANADAIR, CL65, DSNDED BELOW VECTORING ALT PRIOR TO BEING ESTABLISHED ON FINAL APCH.

Narrative: ATC WAS ISSUING VECTORS AS WE APCHED MYR FROM THE NNW. WE CALLED THE ARPT IN SIGHT, AND ATC TOLD US TO MAINTAIN 1600 FT UNTIL ESTABLISHED ON A STRAIGHT-IN FINAL, CLRED VISUAL APCH RWY 35. WE DISCUSSED THE 1600 FT LIMITATION AND 1600 FT WAS SET/CONFIRMED IN THE ALT PRESELECTOR/ALERTER. ON MID-FIELD L DOWNWIND AT 1600 FT WITH THE CAPT HAND-FLYING, TWR CLRED US TO LAND RWY 35 AND REPEATED THE INSTRUCTION TO MAINTAIN 1600 FT UNTIL ON FINAL TO AVOID BANNER TOW ACFT ALONG THE COASTLINE. WE ACKNOWLEDGED THE CLRNC AND 1600 FT INSTRUCTION. OUR LNDG WT REQUIRED USE OF THE 46000 LB V-SPD/MANEUVERING SPD CARD POSITIONED ON THE ACFT COCKPIT CTR PEDESTAL. THE MINIMUM MANEUVERING SPD FOR OUR FLAPS 30 DEG CONFIGN/WT WAS 161 KIAS. ANY TURNS AT LESS THAN 161 KTS ARE RESTR TO 15 DEG BANK ANGLE. PRIOR TO THE CAPT BEGINNING HIS DOWNWIND-TO-BASE TURN, I NOTIFIED HIM THAT OUR MINIMUM SPD WAS 161 KTS (OUR IAS WAS 150 KTS). NO CORRECTION WAS MADE. THE CAPT THEN ENTERED A FULL 30 DEG BANK L TURN AT 145 KIAS AND BEGAN TO DSND FROM 1600 FT WHILE ON BASE. THE ALT ALERTER SOUNDED AS WE WENT 200 FT LOW BUT NO CORRECTION WAS MADE. I TOLD THE CAPT WE WERE 300 FT LOW BUT AGAIN NO CORRECTION WAS MADE AND DSCNT CONTINUED UNTIL WE ROLLED OUT ON FINAL AT 800 FT MSL. ATC MADE NO COMPLAINTS.

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.