Narrative:

It was a midnight arrival. Cleared visual to 35L and keep final turn at dymon. Overshooting winds 060/20; so that was set up to be difficult with the cut approach gave and then cleared visual. Approach mode was armed and 1/2 speed brakes in use. Autothrottle was on at the time. Got a false jump in the glideslope as passing through 35R and the glideslope created issues with flight director's and autothrottle; so I disengaged autothrottle similar to when you forget to activate and confirm. Got the plane controlled; however; I normally keep hand on speed brakes when in use; but the distraction of the glideslope and autothrottle issue broke that habit pattern. Gear down and speed was decaying so I corrected; but loss of situational awareness on the speed brakes caused me confusion as to why I needed this amount of thrust. Captain stowed speed brakes with the checklist and I was correcting for the overshooting winds and aircraft configuration changes and airspeed now returned to normal obviously. The airplane met visual stabilization criteria; no problem and we were not unsafe; but for 10 seconds; my situational awareness was lost due to a false lock on of glideslope; autothrottle jump; disconnecting the autothrottle; overshooting winds and taking my hand off the speed brakes while in use. Landing was uneventful. Another valuable lesson learned about habit patterns; possible fatigue; distractions and how they can create a quick error chain that can snow ball based on environment and circumstances.

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Original NASA ASRS Text

Title: The confluence of several issues while intercepting an ILS caused an A320 flight crew to forget the speed brakes were still deployed as they intercepted the glideslope.

Narrative: It was a midnight arrival. Cleared visual to 35L and keep final turn at Dymon. Overshooting winds 060/20; so that was set up to be difficult with the cut approach gave and then cleared visual. Approach mode was armed and 1/2 speed brakes in use. Autothrottle was on at the time. Got a false jump in the glideslope as passing through 35R and the glideslope created issues with flight director's and autothrottle; so I disengaged autothrottle similar to when you forget to activate and confirm. Got the plane controlled; however; I normally keep hand on speed brakes when in use; but the distraction of the glideslope and autothrottle issue broke that habit pattern. Gear down and speed was decaying so I corrected; but loss of situational awareness on the speed brakes caused me confusion as to why I needed this amount of thrust. Captain stowed speed brakes with the checklist and I was correcting for the overshooting winds and aircraft configuration changes and airspeed now returned to normal obviously. The airplane met visual stabilization criteria; no problem and we were not unsafe; but for 10 seconds; my situational awareness was lost due to a false lock on of glideslope; autothrottle jump; disconnecting the autothrottle; overshooting winds and taking my hand off the speed brakes while in use. Landing was uneventful. Another valuable lesson learned about habit patterns; possible fatigue; distractions and how they can create a quick error chain that can snow ball based on environment and circumstances.

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.