Narrative:

1) takeoff runway bleeds off. 2) passing approximately 2000 ft AGL we began pressurizing aircraft on climb out. 3) approximately 7000 ft the aircraft depressurized rapidly and a cargo door open light illuminated. 4) attempted to contact local ATC to return to airport for landing. Radio call was misunderstood and further climb clearance was issued. 3 more xmissions were sent before we were understood. 5) we returned to land without further incident. We elected to land immediately due to the circumstances which resulted in an overweight landing. Emergency trucks were standing by. Factors: language barrier played a huge role in communicating the exact problem and our needs. Callback conversation with reporter revealed the following information: the reporter stated that the aft door did actually open. Because this was a high altitude bleeds off takeoff the bleeds are opened at some point during the climb after takeoff. In this case the non flying pilot opened both bleeds simultaneously. The reporter is uncertain if the sudden bleed air surge in the pressurization system is what opened the door but the two happened simultaneously. The even bigger problem for this crew was the language barrier attempting to explain to ATC about the need to return and land.

Google
 

Original NASA ASRS Text

Title: A B737-200 CARGO DOOR OPENED IN FLT CAUSING RAPID DEPRESSURIZATION. AN EMER WAS DECLARED WITH A RETURN TO LAND.

Narrative: 1) TKOF RWY BLEEDS OFF. 2) PASSING APPROX 2000 FT AGL WE BEGAN PRESSURIZING ACFT ON CLBOUT. 3) APPROX 7000 FT THE ACFT DEPRESSURIZED RAPIDLY AND A CARGO DOOR OPEN LIGHT ILLUMINATED. 4) ATTEMPTED TO CONTACT LCL ATC TO RETURN TO ARPT FOR LNDG. RADIO CALL WAS MISUNDERSTOOD AND FURTHER CLB CLRNC WAS ISSUED. 3 MORE XMISSIONS WERE SENT BEFORE WE WERE UNDERSTOOD. 5) WE RETURNED TO LAND WITHOUT FURTHER INCIDENT. WE ELECTED TO LAND IMMEDIATELY DUE TO THE CIRCUMSTANCES WHICH RESULTED IN AN OVERWT LNDG. EMER TRUCKS WERE STANDING BY. FACTORS: LANGUAGE BARRIER PLAYED A HUGE ROLE IN COMMUNICATING THE EXACT PROB AND OUR NEEDS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE REPORTER STATED THAT THE AFT DOOR DID ACTUALLY OPEN. BECAUSE THIS WAS A HIGH ALT BLEEDS OFF TKOF THE BLEEDS ARE OPENED AT SOME POINT DURING THE CLB AFTER TKOF. IN THIS CASE THE NON FLYING PILOT OPENED BOTH BLEEDS SIMULTANEOUSLY. THE REPORTER IS UNCERTAIN IF THE SUDDEN BLEED AIR SURGE IN THE PRESSURIZATION SYSTEM IS WHAT OPENED THE DOOR BUT THE TWO HAPPENED SIMULTANEOUSLY. THE EVEN BIGGER PROBLEM FOR THIS CREW WAS THE LANGUAGE BARRIER ATTEMPTING TO EXPLAIN TO ATC ABOUT THE NEED TO RETURN AND LAND.

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.