Narrative:

[We were] climbing out of atl on summit 5 runway 8R. Departure was loaded correctly and autopilot was engaged at 500 ft. The aircraft climbed and intercepted the course to ronni. Approximately six miles prior to ronni the aircraft started a turn to the next fix (rbeka) on the departure. Both the first officer and I noticed it seemed to turn pretty early. About halfway through the turn ATC cleared us direct to summit. She told us that our track had missed ronni and had also mention that it was happening to another aircraft. After that the flight went normally. As the first officer and I were talking about it; he remembered that a check airman had mentioned that some people had been adjusting bank angle parameters in the FMS. We searched around all the pages and eventually found a page under maintenance page two; setup; flight that had an option of a bank angle. I am not sure what exactly that setting does; but it gave a range of 0-15. It was set for seven. I can only assume that that is the bank angle the FMS calculates for turns. We searched our manuals for any reference to bank angle but found none. I guess a more thorough understanding of the FMS and what in fact such a setting should be would be helpful to eliminate such a problem. If in fact the number should be 15; I would hope we could send out a memo; etc. Informing all crews to ensure it is set properly and to not change it.

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Original NASA ASRS Text

Title: An ERJ flight crew reported ATC mentioned a track deviation on departure from ATL. They discovered a bank limitation had been set deep in the FMS menus that may have been a causal factor.

Narrative: [We were] climbing out of ATL on Summit 5 Runway 8R. Departure was loaded correctly and autopilot was engaged at 500 FT. The aircraft climbed and intercepted the course to RONNI. Approximately six miles prior to RONNI the aircraft started a turn to the next fix (RBEKA) on the departure. Both the First Officer and I noticed it seemed to turn pretty early. About halfway through the turn ATC cleared us direct to SUMMIT. She told us that our track had missed RONNI and had also mention that it was happening to another aircraft. After that the flight went normally. As the First Officer and I were talking about it; he remembered that a check airman had mentioned that some people had been adjusting bank angle parameters in the FMS. We searched around all the pages and eventually found a page under Maintenance page two; Setup; Flight that had an option of a bank angle. I am not sure what exactly that setting does; but it gave a range of 0-15. It was set for seven. I can only assume that that is the bank angle the FMS calculates for turns. We searched our manuals for any reference to bank angle but found none. I guess a more thorough understanding of the FMS and what in fact such a setting should be would be helpful to eliminate such a problem. If in fact the number should be 15; I would hope we could send out a memo; etc. informing all crews to ensure it is set properly and to not change it.

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.