Narrative:

Left sju and at around 3500-4000 ft heard 2 loud bangs which shook the closet and lavatory at my jump seat. I noticed a flight attendant from the back checking out the windows to make sure there was no fire as a passenger reported a flash or spark coming out of the l-hand engine. We returned to sju and were given another plane.

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Original NASA ASRS Text

Title: B757 HAS LOUD BANG AND VIBRATION DURING CLB. PAX INDICATES A FLASH FROM L ENG. RETURN TO DEP ARPT.

Narrative: LEFT SJU AND AT AROUND 3500-4000 FT HEARD 2 LOUD BANGS WHICH SHOOK THE CLOSET AND LAVATORY AT MY JUMP SEAT. I NOTICED A FLT ATTENDANT FROM THE BACK CHKING OUT THE WINDOWS TO MAKE SURE THERE WAS NO FIRE AS A PAX RPTED A FLASH OR SPARK COMING OUT OF THE L-HAND ENG. WE RETURNED TO SJU AND WERE GIVEN ANOTHER PLANE.

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.