Narrative:

We were cleared to intercept runway 36 localizer at 1600' MSL. The captain was manually flying the aircraft with autothrottles off and slowing to 160 KTS with flaps at 15 degree down. Both our heads were down looking at the approach plate discussing missed approach procedures. I thought the captain had autothrottles engaged and the speed select at 160 KTS; instead the throttles were at idle and the aircraft was rapidly decelerating through 160 KTS. I was first to notice the decaying airspeed and pushed the throttles up to maximum climb EPR. The captain, now aware of the situation with airspeed continuing to decay compounded by slow engine spoolup time elected to lower the nose to correct the situation. We descended to about 1200' before the aircraft had enough power and airspeed to climb back to 1600'. This occurrence would have been prevented if the captain would have given me control of the aircraft while he briefed the approach (standard operating procedure). Someone must always have positive control of the aircraft especially when none of the magic is hooked up. In high workload situations the autoplt, magic, and positive control are all essential to aviation safety. Due to the time of night, there was little traffic west/O conflict or incident.

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Original NASA ASRS Text

Title: AIRSPEED ALLOWED TO DECAY. ALT LOST DURING RECOVERY.

Narrative: WE WERE CLRED TO INTERCEPT RWY 36 LOC AT 1600' MSL. THE CAPT WAS MANUALLY FLYING THE ACFT WITH AUTOTHROTTLES OFF AND SLOWING TO 160 KTS WITH FLAPS AT 15 DEG DOWN. BOTH OUR HEADS WERE DOWN LOOKING AT THE APCH PLATE DISCUSSING MISSED APCH PROCS. I THOUGHT THE CAPT HAD AUTOTHROTTLES ENGAGED AND THE SPD SELECT AT 160 KTS; INSTEAD THE THROTTLES WERE AT IDLE AND THE ACFT WAS RAPIDLY DECELERATING THROUGH 160 KTS. I WAS FIRST TO NOTICE THE DECAYING AIRSPD AND PUSHED THE THROTTLES UP TO MAX CLB EPR. THE CAPT, NOW AWARE OF THE SITUATION WITH AIRSPD CONTINUING TO DECAY COMPOUNDED BY SLOW ENG SPOOLUP TIME ELECTED TO LOWER THE NOSE TO CORRECT THE SITUATION. WE DSNDED TO ABOUT 1200' BEFORE THE ACFT HAD ENOUGH PWR AND AIRSPD TO CLB BACK TO 1600'. THIS OCCURRENCE WOULD HAVE BEEN PREVENTED IF THE CAPT WOULD HAVE GIVEN ME CTL OF THE ACFT WHILE HE BRIEFED THE APCH (STANDARD OPERATING PROC). SOMEONE MUST ALWAYS HAVE POSITIVE CTL OF THE ACFT ESPECIALLY WHEN NONE OF THE MAGIC IS HOOKED UP. IN HIGH WORKLOAD SITUATIONS THE AUTOPLT, MAGIC, AND POSITIVE CTL ARE ALL ESSENTIAL TO AVIATION SAFETY. DUE TO THE TIME OF NIGHT, THERE WAS LITTLE TFC W/O CONFLICT OR INCIDENT.

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.