Narrative:

Shortly after takeoff (before gear retracted); the pilot's attitude indicator failed; followed by warning messages. Considering the weather at the field; and the prior history of the airplane's maintenance problems concerning the ahrs [attitude and heading reference system] computer; I decided to return to the field. There was a small window of opportunity to return under VFR conditions and I took it. We were going to an airport with expensive fuel; so I had topped off the airplane. Due to the amount of fuel we had on board and the fact that we were airborne for 4 minutes; an overweight landing was accomplished. Aircraft was grounded for AHRS1 failure and an overweight landing.

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Original NASA ASRS Text

Title: An LR40 flight crew returned and landed overweight at its departure airport when the attitude indicator failed immediately after takeoff.

Narrative: Shortly after takeoff (before gear retracted); the pilot's attitude indicator failed; followed by warning messages. Considering the weather at the field; and the prior history of the airplane's maintenance problems concerning the AHRS [Attitude and Heading Reference System] computer; I decided to return to the field. There was a small window of opportunity to return under VFR conditions and I took it. We were going to an airport with expensive fuel; so I had topped off the airplane. Due to the amount of fuel we had on board and the fact that we were airborne for 4 minutes; an overweight landing was accomplished. Aircraft was grounded for AHRS1 failure and an overweight landing.

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.