Narrative:

Flying into las; we were assigned a visual approach to runway 25L and to descend via the KEPEC3 RNAV arrival. Flying the KEPEC3 RNAV arrival; we passed ipumy at 230 knots and 11;000 ft. We were told at that time to change runway to visual approach 19R. We were given a 090 degree vector and subsequent step downs in altitude until 7000 ft and then directed to slow to 170 knots. I configured to flaps 5. We were given a north vector to an intercept position between eastr and towen of the RNAV visual 19L/right. We were directed to descend to 5000 ft. I configured with landing gear down and flaps 15. We were cleared the visual approach runway 19R. I then continued slowing to vt of 131 with flaps 30. I intercepted the LNAV course between towen and eastr at 4400 feet. The MCP was in LNAV; VNAV. Determining that I need to correct higher altitude; I called for 40 flaps momentarily. As I continued descent through 6000 ft; we realized that we were too high and it was better to discontinue the approach. The pilot monitoring (pm) recommended that we ask for a right 360 degree spacing maneuver to line ourselves up on final. We agreed and the pm asked for the maneuver from las tower. Tower gave us a 260 vector and to maintain 4000 ft. I selected heading select 270 and the pm selected 4000 ft in the altitude window. I called for flaps 30 as we descended from 4300 ft on the way down to 4000 ft. We were given a northern heading. As the aircraft reached 4000 ft; I noticed the airspeed trend vector going below vt of 131. I observed the autothrottles not making the adequate adjustment; so I placed them manually up to full power to stop the trend. The aircraft pitched up and started climbing above 4000 ft; the stick shaker momentarily came on. Recognizing this; I turned off the autopilot/autothrottles and reduced aoa. The airspeed recovered and I called for flaps 15. We stabilized and continued for a visual approach runway 19R. 1. Late change in runway assignments: recognizing that I was on short vectors for runway 19R; I will have to configure a lot earlier to adjust for a more expeditious descent. I also will give myself space by requesting to go to points on the approach segments that will give me adequate time to slow down and go down.2. Use the appropriate level of automation for the task at hand. I will turn off autopilot and fly the jet manually. We were in a visual environment; executing a VFR spacing maneuver. I will turn off autopilot and autothrottles and target the speed bug to vt+10 as I maneuver and keep a better crosscheck of airspeed and altitude trends while in a visual maneuvering environment.

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Original NASA ASRS Text

Title: B737-700 flight crew describes an unstabilized approach that results from a late runway change from Runway 25L to Runway 19R at LAS. The go-around is commenced above 4;000 FT but insufficient thrust is added and the stick shaker is activated. With more thrust and lowering the nose; the stick shaker is silenced and the next visual approach is successful.

Narrative: Flying into LAS; we were assigned a visual approach to Runway 25L and to descend via the KEPEC3 RNAV Arrival. Flying the KEPEC3 RNAV Arrival; we passed IPUMY at 230 knots and 11;000 FT. We were told at that time to change runway to visual approach 19R. We were given a 090 degree vector and subsequent step downs in altitude until 7000 FT and then directed to slow to 170 knots. I configured to flaps 5. We were given a north vector to an intercept position between EASTR and TOWEN of the RNAV Visual 19L/R. We were directed to descend to 5000 FT. I configured with landing gear down and flaps 15. We were cleared the visual approach Runway 19R. I then continued slowing to Vt of 131 with flaps 30. I intercepted the LNAV course between TOWEN and EASTR at 4400 feet. The MCP was in LNAV; VNAV. Determining that I need to correct higher altitude; I called for 40 flaps momentarily. As I continued descent through 6000 FT; we realized that we were too high and it was better to discontinue the approach. The pilot monitoring (PM) recommended that we ask for a right 360 degree spacing maneuver to line ourselves up on final. We agreed and the PM asked for the maneuver from LAS Tower. Tower gave us a 260 vector and to maintain 4000 FT. I selected heading select 270 and the PM selected 4000 FT in the altitude window. I called for flaps 30 as we descended from 4300 FT on the way down to 4000 FT. We were given a northern heading. As the aircraft reached 4000 FT; I noticed the airspeed trend vector going below Vt of 131. I observed the autothrottles not making the adequate adjustment; so I placed them manually up to full power to stop the trend. The aircraft pitched up and started climbing above 4000 FT; the stick shaker momentarily came on. Recognizing this; I turned off the autopilot/autothrottles and reduced AOA. The airspeed recovered and I called for flaps 15. We stabilized and continued for a visual approach Runway 19R. 1. Late change in runway assignments: Recognizing that I was on short vectors for Runway 19R; I will have to configure a lot earlier to adjust for a more expeditious descent. I also will give myself space by requesting to go to points on the approach segments that will give me adequate time to slow down and go down.2. Use the appropriate level of automation for the task at hand. I will turn off autopilot and fly the jet manually. We were in a visual environment; executing a VFR spacing maneuver. I will turn off autopilot and autothrottles and target the speed bug to Vt+10 as I maneuver and keep a better crosscheck of airspeed and altitude trends while in a visual maneuvering environment.

Data retrieved from NASA's ASRS site 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.