B757 first officer reports a leading edge slat disagree light upon initial flap selection during app...

Narrative:

On vectors to final; we began to configure the aircraft. At extension of flaps; the leading edge slat disagree light illuminated. I ran the checklist to get the flaps extended; but by final we had only gotten the flaps to 5. We decided to do a map and ask for an extended final to complete the checklist. During the go around; we exceeded the flaps 5 speed. On completion of the QRH checklist we declared an emergency and landed uneventfully. Electrical extension of the flaps takes a very long time. The current checklist is very long and very confusing; to ensure exact compliance with the QRH without confusion; plan on an extended duration pattern.

Original NASA ASRS Text

Title: B757 First Officer reports a leading edge slat disagree light upon initial flap selection during approach. QRH procedures cannot be accomplished in a timely manner leading to a go around and a flap overspeed with the flaps set at five. A flaps 20 landing ensues after declaring an emergency.

Narrative: On vectors to final; we began to configure the aircraft. At extension of flaps; the LEADING EDGE SLAT DISAGREE LIGHT illuminated. I ran the checklist to get the flaps extended; but by final we had only gotten the flaps to 5. We decided to do a MAP and ask for an extended final to complete the checklist. During the Go Around; we exceeded the flaps 5 speed. On completion of the QRH checklist we declared an emergency and landed uneventfully. Electrical extension of the flaps takes a very long time. The current checklist is very long and very confusing; to ensure exact compliance with the QRH without confusion; plan on an extended duration pattern.

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.

Attributes
ACN	985364
Time
Date	201112
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Landing
Component
Aircraft Component	Leading Edge Slat
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Speed All Types

B757 first officer reports a leading edge slat disagree light upon initial flap selection during approach. QRH procedures cannot be accomplished in a timely manner leading to a go around and a flap overspeed with the flaps set at five. A flaps 20 landing ensues after declaring an emergency.