Narrative:

We called for push; ground said it would be a while; another carrier was pushing in alley. We finally received clearance to push. While starting the number two engine; ground said expect 24L; which we had in box. While starting the number one engine; ground said expect 25R; due to vip movement. First officer continued start while I went into the performance computer to get numbers for that runway. After we programmed the new data; ground said if we can taxi immediately we could get 24L again. Once again we went into the performance computer to change data; and started to taxi. We forgot to do the before taxi checklist. Caught on taxi out when did throttle check; and got horn since we didn't put out flaps. At that time put flaps out and ran before taxi checklist; and then before takeoff checklist.

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Original NASA ASRS Text

Title: B737-700 Captain reported taxiing without running the before taxi checklist when they were distracted by multiple departure runway changes.

Narrative: We called for push; Ground said it would be a while; another carrier was pushing in alley. We finally received clearance to push. While starting the number two engine; Ground said expect 24L; which we had in box. While starting the number one engine; Ground said expect 25R; due to VIP movement. FO continued start while I went into the performance computer to get numbers for that runway. After we programmed the new data; Ground said if we can taxi immediately we could get 24L again. Once again we went into the performance computer to change data; and started to taxi. We forgot to do the before taxi checklist. Caught on taxi out when did throttle check; and got horn since we didn't put out flaps. At that time put flaps out and ran before taxi checklist; and then before takeoff checklist.

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.