Narrative:

The aircraft had come from maintenance and had not been revenue flown for approximately 14 days. Notation was made on initial takeoff that #1 engine was slow to spool. The first leg was flown by the captain to a VFR and VMC constant descent approach and landing. Subsequent takeoff accomplished by the first officer was also evident of an extremely slow to spool #1 engine. Autopilot was coupled throughout descent and approach. Descent was uneventful and the aircraft was vectored for an ILS to runway 35. The aircraft entered a solid deck at approx 11;000'. The weather was approximately 400 ft ovc/5NM visibility and 10-15 KTS right crosswind at FAF. Course intercept occurred prior to initial approach fix at 5000 ft MSL. ATC requested to maintain 170 KTS until the final approach fix. 3000 ft was set in the altitude window of the MCP. A gradual descent was established. Flaps to 15 and landing gear were established sometime prior to the final approach fix. The aircraft was slightly left of the localizer course throughout with a heading a few degrees to the left. At approximately 8 NM to the final approach fix; the aircraft was slowly reaching 3000 ft MSL. The first officer; while initiating an instrument crosscheck; began to simultaneously add power abruptly to his known reference point for the configuration; called for flaps 30; noticed the GS V bar was descending at 1/4 dot from above the aircraft cue. The aircraft continued descent through 3000 ft upon which the first officer fixated on the altimeter; GS reference and vvi. The aircraft descended approximately 80 ft below. At this time the aircraft was approximately 4 NM from the final approach fix and began to pitch up to the GS reference to a vvi of 800 FPM. The first officer immediately began forward pressure on the control column. Airspeed began to decay rapidly. The first officer first noticed the speed decay passing through target speed; which rapidly became 5 below in less than a second. The first officer; knowing of an impending stick shaker at this time; began applying forward column pressure and power. After the captain had reached over to set flaps 30; he noticed the airspeed decay and said easy now as the speed was decaying just past target realizing I was making a significant correction. At the time we were 10-15 KTS below target and the captain and first officer both popped the control column forward just as the stick shaker started. The first officer now pushed full forward and shoved the power further and started to run nose down trim to disengage the autopilot. The shaker lasted less than 2 seconds. The first officer elected to continue a descent another 350 ft leveling off until significant airspeed was acquired. At this point the aircraft was left full scale localizer deflection. The first officer said and initiated a go-around. Another approach was executed and the aircraft landed uneventfully. Although time dilation is a factor when things go south; I feel pretty confident the time line is very close. From start to finish with all the factors impacting at once; I feel it only took seconds for this situation to fully develop from a perceived stable flight control/throttle position. I accept full responsibility for the under speed condition of the aircraft. Besides human error; three factors combined to rapidly develop a situation which should have not happened: significant semi-asymmetrical reduction in thrust; weather; and automation. I accept full responsibility for the occurrence. However; a few aggravating conditions along with human error exacerbated this occurrence within seconds. In this -300; the aircraft sought to pitch up to GS intercept while I expected the aircraft to pitch over during flaps 30 extension which was occurring simultaneously. I set throttle position for the flight conditions/parameters at the time by feel and then fine tune them visually/auditorily (quadrant; N1s; noise). I was not able to and frankly had to drop that from a crosscheck when I focused on an aircraft descending then ascending and wondering why this was happening. I fixated on ADI; vvi; and altimeter losing the airspeed momentarily. Once recognized; I was on the back side of the curve. I feel this was no ordinary simulator profile recovery. While all good the simulator is; it sets up only for a perfectly flown known condition. Here comes a stall configure trim; trim; trim; wait; wait; ok now. I always ride and I had ridden the flight controls during this situation. If not; with the rapidly changing dynamics; it could have been different. The only comment from the flight attendants was to why we went around. Automation; especially autopilot issues when intercepting; need addressing (GS descent/localizer stability). The simulator does it so perfectly; but in the real world; the aircraft do not. Engine spool up parameters need addressing. Finally; ride the controls in demanding flight conditions which this was. If it had been VMC/VFR; my workload would have been significantly reduced and a few parameters been negated. However; we don't always get to fly the simulator profile day-to-day.

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Original NASA ASRS Text

Title: A B737-300 First Officer flying an ILS entered a stall warning regime after fixating on instruments other than airspeed as the aircraft slowed while capturing the glide slope. A go-around was executed followed by a second normal approach.

Narrative: The aircraft had come from Maintenance and had not been revenue flown for approximately 14 days. Notation was made on initial takeoff that #1 engine was slow to spool. The first leg was flown by the Captain to a VFR and VMC constant descent approach and landing. Subsequent takeoff accomplished by the First Officer was also evident of an extremely slow to spool #1 engine. Autopilot was coupled throughout descent and approach. Descent was uneventful and the aircraft was vectored for an ILS to Runway 35. The aircraft entered a solid deck at approx 11;000'. The weather was approximately 400 FT OVC/5NM VIS and 10-15 KTS right crosswind at FAF. Course intercept occurred prior to initial approach fix at 5000 FT MSL. ATC requested to maintain 170 KTS until the final approach fix. 3000 FT was set in the altitude window of the MCP. A gradual descent was established. Flaps to 15 and landing gear were established sometime prior to the final approach fix. The aircraft was slightly left of the localizer course throughout with a heading a few degrees to the left. At approximately 8 NM to the final approach fix; the aircraft was slowly reaching 3000 FT MSL. The First Officer; while initiating an instrument crosscheck; began to simultaneously add power abruptly to his known reference point for the configuration; called for Flaps 30; noticed the GS V bar was descending at 1/4 dot from above the aircraft cue. The aircraft continued descent through 3000 FT upon which the First Officer fixated on the altimeter; GS reference and VVI. The aircraft descended approximately 80 FT below. At this time the aircraft was approximately 4 NM from the final approach fix and began to pitch up to the GS reference to a VVI of 800 FPM. The First Officer immediately began forward pressure on the control column. Airspeed began to decay rapidly. The First Officer first noticed the speed decay passing through target speed; which rapidly became 5 below in less than a second. The First Officer; knowing of an impending stick shaker at this time; began applying forward column pressure and power. After the Captain had reached over to set Flaps 30; he noticed the airspeed decay and said easy now as the speed was decaying just past target realizing I was making a significant correction. At the time we were 10-15 KTS below target and the Captain and First Officer both popped the control column forward just as the stick shaker started. The First Officer now pushed full forward and shoved the power further and started to run nose down trim to disengage the autopilot. The shaker lasted less than 2 seconds. The First Officer elected to continue a descent another 350 FT leveling off until significant airspeed was acquired. At this point the aircraft was left full scale localizer deflection. The First Officer said and initiated a go-around. Another approach was executed and the aircraft landed uneventfully. Although time dilation is a factor when things go south; I feel pretty confident the time line is very close. From start to finish with all the factors impacting at once; I feel it only took seconds for this situation to fully develop from a perceived stable flight control/throttle position. I accept full responsibility for the under speed condition of the aircraft. Besides human error; three factors combined to rapidly develop a situation which should have not happened: significant semi-asymmetrical reduction in thrust; weather; and automation. I accept full responsibility for the occurrence. However; a few aggravating conditions along with human error exacerbated this occurrence within seconds. In this -300; the aircraft sought to pitch up to GS intercept while I expected the aircraft to pitch over during Flaps 30 extension which was occurring simultaneously. I set throttle position for the flight conditions/parameters at the time by feel and then fine tune them visually/auditorily (Quadrant; N1s; noise). I was not able to and frankly had to drop that from a crosscheck when I focused on an aircraft descending then ascending and wondering why this was happening. I fixated on ADI; VVI; and altimeter losing the airspeed momentarily. Once recognized; I was on the back side of the curve. I feel this was no ordinary simulator profile recovery. While all good the simulator is; it sets up only for a perfectly flown known condition. Here comes a stall configure trim; trim; trim; wait; wait; ok now. I always ride and I had ridden the flight controls during this situation. If not; with the rapidly changing dynamics; it could have been different. The only comment from the Flight Attendants was to why we went around. Automation; especially autopilot issues when intercepting; need addressing (GS descent/localizer stability). The simulator does it so perfectly; but in the real world; the aircraft do not. Engine spool up parameters need addressing. Finally; ride the controls in demanding flight conditions which this was. If it had been VMC/VFR; my workload would have been significantly reduced and a few parameters been negated. However; we don't always get to fly the simulator profile day-to-day.

Data retrieved from NASA's ASRS site as of April 2012 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.