Narrative:

While taxiing out; during right engine start; the aircraft lost all alternating current (AC) electrical power. The captain immediately performed the correct memory item (emergency power switch on); and brought the aircraft to a stop. Knowing we had number 1 radio available; he communicated the issue to ground control. Interestingly; the left engine was running normally; and the APU was as well. We could only assume that the left engine driven generator and APU generator were operating normally as they were showing normal volts and frequencies available; but were not powering the AC busses. I retrieved the QRH; and we performed the complete loss of AC power checklist. Obviously; some of the steps were not applicable. The resets called for in the checklist (bat direct bus feed breaker; or resetting the engine and APU generators) did not restore power to any of the busses. We noted the time; and communicated with ATC; and the company (operations and maintenance). The captain made the decision to not taxi the aircraft (wisely in my opinion); as the aircraft was in a safe position; and we were in communication with ATC; and maintenance was on the way to tow our aircraft back to [the] terminal. The captain did a great job communicating with the passengers; the flight attendants; and ATC. Maintenance arrived with a tug after approximately 30 minutes. The captain informed ground that we may lose radio capability; as the battery life on emergency power is only available for approximately 30 minutes. Ground said that was not a problem as they would also be in communication with the tug. We were then towed [to the gate]. The radio did fail enroute (as expected).

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Original NASA ASRS Text

Title: Air carrier First Officer reported losing all electrical power during taxi out. Checklist failed to restore power; and the aircraft was towed back to the gate.

Narrative: While taxiing out; during right engine start; the aircraft lost all Alternating Current (AC) electrical power. The Captain immediately performed the correct memory item (Emergency Power switch ON); and brought the aircraft to a stop. Knowing we had number 1 radio available; he communicated the issue to Ground Control. Interestingly; the left engine was running normally; and the APU was as well. We could only assume that the left engine driven generator and APU generator were operating normally as they were showing normal volts and frequencies available; but were not powering the AC busses. I retrieved the QRH; and we performed the Complete Loss of AC Power checklist. Obviously; some of the steps were Not Applicable. The resets called for in the checklist (BAT DIRECT BUS FEED breaker; or resetting the engine and APU generators) did not restore power to any of the busses. We noted the time; and communicated with ATC; and the company (Operations and Maintenance). The Captain made the decision to not taxi the aircraft (wisely in my opinion); as the aircraft was in a safe position; and we were in communication with ATC; and Maintenance was on the way to tow our aircraft back to [the] terminal. The Captain did a great job communicating with the passengers; the flight attendants; and ATC. Maintenance arrived with a tug after approximately 30 minutes. The Captain informed Ground that we may lose radio capability; as the battery life on Emergency Power is only available for approximately 30 minutes. Ground said that was not a problem as they would also be in communication with the tug. We were then towed [to the gate]. The radio did fail enroute (as expected).

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.