Narrative:

After normal takeoff during climb through about 11;000 we heard and felt a pressurization bump. Cabin altitude was climbing and approaching 10;000. We leveled near 14;000 MSL; and then executed a descent back to 10;000 MSL. [We] received cabin altitude alert while leveling at 10;000. Complied with QRH; contacted operations and decided to return to our departure airport. On post flight I noted a ruptured panel and scrape on underside of rear fuselage.I think I missed the damage on preflight. I think the damage on post flight was probably more evident than the preflight due to panel that may have ruptured during flight hanging down/not flush.

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Original NASA ASRS Text

Title: Following a return to their departure airport due to the failure of the aircraft to pressurize the flight crew of a B757-200 discovered scrapes and a blown out panel on the aft lower fuselage.

Narrative: After normal takeoff during climb through about 11;000 we heard and felt a pressurization bump. Cabin altitude was climbing and approaching 10;000. We leveled near 14;000 MSL; and then executed a descent back to 10;000 MSL. [We] received Cabin Altitude alert while leveling at 10;000. Complied with QRH; contacted Operations and decided to return to our departure airport. On post flight I noted a ruptured panel and scrape on underside of rear fuselage.I think I missed the damage on preflight. I think the damage on post flight was probably more evident than the preflight due to panel that may have ruptured during flight hanging down/not flush.

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.