Narrative:

[We] departed the gate with 48 passengers; began taxi to runway 36. While in taxi line for takeoff; thunderstorms developed over and around the airport; stopping nearly all traffic. ATC advised aircraft waiting for takeoff could shut down engines; so we started our APU and shut down our engines. A few minutes later the APU generator light began flashing back and forth from on to warn. Other lights in the cockpit began surging from bright to dim and back. Captain turned off the APU generator and the APU and attempted to start the #2 engine on batteries. The engine was going hot on the start so the captain aborted the start around 850 itt. A second attempt a few minutes later produced the same result. We attempted to restart the APU but it had fail displayed on the power button. At this point we realized we were stuck on only battery power with no air conditioning. We notified ground that we were unable to move and would need to be towed. We then notified operations and dispatch that we would need buses to get the passengers and a tow for the aircraft. Operations advised us that they would arrange buses; but they would be unable to come out because the ramp was closed for lightning. The captain advised all parties that we had a full plane with no air conditioning and the passengers needed to deplane as soon as possible. Finally an hour later the weather abated enough for the buses to come to the plane. The passengers deplaned and were bussed back. We stayed with the plane until towed back to the terminal. At no time was an emergency declared.

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Original NASA ASRS Text

Title: A DHC8-300 APU failed while holding on a taxiway for thunderstorms around the airport to clear so unable to start an engine the passengers were bused to the terminal and the aircraft towed.

Narrative: [We] departed the gate with 48 passengers; began taxi to Runway 36. While in taxi line for takeoff; thunderstorms developed over and around the airport; stopping nearly all traffic. ATC advised aircraft waiting for takeoff could shut down engines; so we started our APU and shut down our engines. A few minutes later the APU Generator light began flashing back and forth from ON to WARN. Other lights in the cockpit began surging from bright to dim and back. Captain turned off the APU generator and the APU and attempted to start the #2 engine on batteries. The engine was going hot on the start so the Captain aborted the start around 850 ITT. A second attempt a few minutes later produced the same result. We attempted to restart the APU but it had FAIL displayed on the power button. At this point we realized we were stuck on only battery power with no air conditioning. We notified Ground that we were unable to move and would need to be towed. We then notified Operations and Dispatch that we would need buses to get the passengers and a tow for the aircraft. Operations advised us that they would arrange buses; but they would be unable to come out because the ramp was closed for lightning. The Captain advised all parties that we had a full plane with no air conditioning and the passengers needed to deplane as soon as possible. Finally an hour later the weather abated enough for the buses to come to the plane. The passengers deplaned and were bussed back. We stayed with the plane until towed back to the terminal. At no time was an emergency declared.

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.