Narrative:

North and descending from FL240 to 12000 ft. Selected flight level change speed 305 KTS when current speed was 295 KTS. Aircraft pitched over to 18 degrees nose low and what seemed to be near zero G. I clicked off the autoplt as speed was passing 305 degrees and used full speed brakes and a large amount of backpressure to level/slow aircraft. We got the overspd clacker for around 5 seconds and overspd was around 2 KTS too fast. This was a ferry flight.

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Original NASA ASRS Text

Title: A 'FLT CREW' DESCENT WAS INITIATED WHILE THE AUTOPILOT WAS ENGAGED; AND THE B757-200 PITCHED OVER EXCESSIVELY CAUSING ACFT OVERSPEED.

Narrative: N AND DSNDING FROM FL240 TO 12000 FT. SELECTED FLT LEVEL CHANGE SPD 305 KTS WHEN CURRENT SPD WAS 295 KTS. ACFT PITCHED OVER TO 18 DEGS NOSE LOW AND WHAT SEEMED TO BE NEAR ZERO G. I CLICKED OFF THE AUTOPLT AS SPD WAS PASSING 305 DEGS AND USED FULL SPD BRAKES AND A LARGE AMOUNT OF BACKPRESSURE TO LEVEL/SLOW ACFT. WE GOT THE OVERSPD CLACKER FOR AROUND 5 SECONDS AND OVERSPD WAS AROUND 2 KTS TOO FAST. THIS WAS A FERRY FLT.

Data retrieved from NASA's ASRS site as of May 2009 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.