Narrative:

While engine power was reducing from maximum takeoff thrust to climb 2, there was a jolt similar to a food cart hitting a bulkhead. The autothrottle then increased engine power back to a high power setting. The first officer pulled the throttle back to the reduced setting, but it then went back to a high climb power setting. Then first officer therefore disconnected the autothrottle (airspeed was building). During the distraction, airspeed increased above 250 KTS. Speed was then returned back to 250 KTS. The engine parameters appeared normal, and pressurization appeared normal. The flight attendants reported hearing and feeling the jolt. 1 flight attendant reported seeing a flash behind the left wing. 3 passenger also reported seeing a flash behind the left engine.

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Original NASA ASRS Text

Title: A B757-200 IN INITIAL CLB AT 2000 FT EXPERIENCED A JOLT FOLLOWED BY THE AUTOTHROTTLE INCREASING ENG TO A HIGH PWR SETTING. CABIN ATTENDANT AND PAX RPT SEEING A FLASH BEHIND L ENG.

Narrative: WHILE ENG PWR WAS REDUCING FROM MAX TKOF THRUST TO CLB 2, THERE WAS A JOLT SIMILAR TO A FOOD CART HITTING A BULKHEAD. THE AUTOTHROTTLE THEN INCREASED ENG PWR BACK TO A HIGH PWR SETTING. THE FO PULLED THE THROTTLE BACK TO THE REDUCED SETTING, BUT IT THEN WENT BACK TO A HIGH CLB PWR SETTING. THEN FO THEREFORE DISCONNECTED THE AUTOTHROTTLE (AIRSPD WAS BUILDING). DURING THE DISTR, AIRSPD INCREASED ABOVE 250 KTS. SPD WAS THEN RETURNED BACK TO 250 KTS. THE ENG PARAMETERS APPEARED NORMAL, AND PRESSURIZATION APPEARED NORMAL. THE FLT ATTENDANTS RPTED HEARING AND FEELING THE JOLT. 1 FLT ATTENDANT RPTED SEEING A FLASH BEHIND THE L WING. 3 PAX ALSO RPTED SEEING A FLASH BEHIND THE L ENG.

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.