Narrative:

Established on localizer runway 01 into dca. At approximately 18 miles out we were cleared for the approach and selected 'approach' on FCU. Autoplt aggressively pitched up and began rapid climb, autoplt disconnected while throttles advanced. Manually controled aircraft and descended back down to 4000 ft to our assigned altitude. Intercepted GS and reestablished autoplt. Again, autoplt pitched up performing the same error. Autoplt was left off and approach flown manually without further incident.

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Original NASA ASRS Text

Title: A319 CREW HAD ACFT PITCH UP WHEN ENGAGING THE AUTOPLT.

Narrative: ESTABLISHED ON LOC RWY 01 INTO DCA. AT APPROX 18 MILES OUT WE WERE CLRED FOR THE APCH AND SELECTED 'APCH' ON FCU. AUTOPLT AGGRESSIVELY PITCHED UP AND BEGAN RAPID CLB, AUTOPLT DISCONNECTED WHILE THROTTLES ADVANCED. MANUALLY CTLED ACFT AND DESCENDED BACK DOWN TO 4000 FT TO OUR ASSIGNED ALT. INTERCEPTED GS AND REESTABLISHED AUTOPLT. AGAIN, AUTOPLT PITCHED UP PERFORMING THE SAME ERROR. AUTOPLT WAS L OFF AND APCH FLOWN MANUALLY WITHOUT FURTHER INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 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.