Narrative:

We were departing mid-morning during VMC conditions. The first officer was the pilot flying. Everything was normal up to and during the takeoff roll. Shortly after rotation; the air driven generator deployed. After running the after takeoff checklist; I ran the QRH; and we planned to return. While the air driven generator was deployed; we noticed that all electric indications on the electric synoptic page appeared normal; and all buses were powered. The only unusual EICAS message was the amber 'left windshield heat' caution message. There were no messages pertaining to the electrical system. We of course had not touched the air driven generator manual release handle. With all indications appearing normal; it appeared that the air driven generator should not have deployed. Due to the uncertainty of the air driven generator; and the noise in the flight deck; we decided to return for a normal landing. We checked the fuel and anticipated landing weight; which was right at the maximum. We notified the dispatcher via ACARS; and the flight release was amended. We notified the flight attendant as well as the passengers that we were returning for a normal landing; and the reason. The flight was concluded without further incident. The air driven generator deployed when it apparently didn't need to. This resulted in a high workload to run checklists and prepare for an air return; all while the air driven generator was creating a noisy flight deck.

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Original NASA ASRS Text

Title: CRJ200 Captain experiences an ADG deployment shortly after takeoff for no apparent reason. The crew elects to return to the departure airport for an uneventful landing at maximum landing weight.

Narrative: We were departing mid-morning during VMC conditions. The First Officer was the pilot flying. Everything was normal up to and during the takeoff roll. Shortly after rotation; the ADG deployed. After running the After Takeoff checklist; I ran the QRH; and we planned to return. While the ADG was deployed; we noticed that all electric indications on the electric synoptic page appeared normal; and all buses were powered. The only unusual EICAS message was the amber 'L Windshield Heat' caution message. There were no messages pertaining to the electrical system. We of course had not touched the ADG manual release handle. With all indications appearing normal; it appeared that the ADG should not have deployed. Due to the uncertainty of the ADG; and the noise in the flight deck; we decided to return for a normal landing. We checked the fuel and anticipated landing weight; which was right at the maximum. We notified the Dispatcher via ACARS; and the flight release was amended. We notified the Flight Attendant as well as the passengers that we were returning for a normal landing; and the reason. The flight was concluded without further incident. The ADG deployed when it apparently didn't need to. This resulted in a high workload to run checklists and prepare for an air return; all while the ADG was creating a noisy flight deck.

Data retrieved from NASA's ASRS site as of July 2013 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.