Narrative:

[We] departed on ETOPS flight with both generators on APU bus. At 10;000 feet flight attendants said ovens were not working. Checked and cycled both galley switches power on and off. Asked the flight attendants if the breakers were in and they were. Immediately called maintenance control and they said sounds like load shed. That is when I noticed the gen bus lights. Changed switched position and continued normally. I take responsibility for the mistake and obviously during the checklist I answered that the generators were on when; in fact; they were not. I would like to think that I have excellent checklist discipline because I insist on checklist precision and even brief that when I start a new flight segment. So I have to dig deep slow down and pay more attention. No other action taken and flight continue normally to destination. One factor that the first officer and I discussed is the intensity of the lights and ambient outside sunlight made viewing the lights difficult even when looking directly at the lights. We both thought that we had looked at the lights and even double checked. Even looking near that area where the galley power switches are located we both did not notice the lights. Again were pointed directly into a setting sun and the light was directly in the forward windscreen. There is no warning for taking off in this configuration and that probably should be designed into the aircraft. This might be so because there is auto switching should the APU be shutdown in this configuration. Bottom line this is my error and a crew error and vigilance and slowing down are the solution.

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Original NASA ASRS Text

Title: A B737 Captain reported that the aircraft took off with both buses on the APU generator. The Pilots did not see the generator lights' status because the sun's brightness overwhelmed the relatively dim electrical panel lights.

Narrative: [We] departed on ETOPS flight with both Generators on APU Bus. At 10;000 feet Flight Attendants said ovens were not working. Checked and cycled both galley switches power ON and OFF. Asked the Flight Attendants if the breakers were in and they were. Immediately called Maintenance Control and they said sounds like load shed. That is when I noticed the Gen Bus lights. Changed switched position and continued normally. I take responsibility for the mistake and obviously during the checklist I answered that the generators were ON when; in fact; they were not. I would like to think that I have excellent checklist discipline because I insist on checklist precision and even brief that when I start a new flight segment. So I have to dig deep slow down and pay more attention. No other action taken and flight continue normally to destination. One factor that the First Officer and I discussed is the intensity of the lights and ambient outside sunlight made viewing the lights difficult even when looking directly at the lights. We both thought that we had looked at the lights and even double checked. Even looking near that area where the galley power switches are located we both did not notice the lights. Again were pointed directly into a setting sun and the light was directly in the forward windscreen. There is no warning for taking off in this configuration and that probably should be designed into the aircraft. This might be so because there is auto switching should the APU be shutdown in this configuration. Bottom line this is my error and a crew error and vigilance and slowing down are the solution.

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.