Narrative:

[I was] cleared for the ruudy 4 departure from teb. On climbout turned to intercept course 260 to wentz. Autopilot did not want to engage and during troubleshooting I passed through the required 1;500 MSL crossing altitude at wentz. [I] executed an immediate descent back to 1;500 MSL. Approximately 400 ft overshoot. Will not rely on immediate autopilot engagement next time and will plan on hand flying to an altitude allowing time for possible autopilot problems.

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Original NASA ASRS Text

Title: An EA50 autopilot would not engage on a TEB RUUDY 4 departure; so the distracted pilot did not level at the WENTZ 1;500 FT constraint but descended to it after realizing his error.

Narrative: [I was] cleared for the RUUDY 4 departure from TEB. On climbout turned to intercept course 260 to WENTZ. Autopilot did not want to engage and during troubleshooting I passed through the required 1;500 MSL crossing altitude at WENTZ. [I] executed an immediate descent back to 1;500 MSL. Approximately 400 FT overshoot. Will not rely on immediate autopilot engagement next time and will plan on hand flying to an altitude allowing time for possible autopilot problems.

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.