Narrative:

During climb out from manchester, england, the cabin altitude warning horn sounded as we passed through FL270. I removed my boom microphone/headset while donning my oxygen mask and did not hear a transmission that the first officer made to london control. When I got back into the communication loop, I heard london asking what the nature of our emergency was. I responded that we were having a problem with the pressurization. The controller then told us to squawk 7700, which I did, and cleared us to descend to FL240. By this time the so had resolved the problem and I told london that we did not want to descend and would like to maintain our present altitude to ensure that we had in fact resolved the problem. Shortly thereafter I informed london control that we did have everything back to normal and he asked what our intentions were. I told him we wanted to resume the climb to FL310 and requested clearance direct to 55N 10W, our oceanic entry fix. He cleared us as requested and switched us to scottish control. Scottish asked if the passenger oxygen masks had been deployed and I told him that we managed to avoid that. I then asked scottish for a new transponder code which he supplied. After everything settled, and we had the FMS reprogrammed with the revised oceanic clearance we received just prior to the pressurization problem, I began wondering what had caused london control to think we were declaring an emergency and wanted to descend. I asked the first officer what he had said to london while I had my headset off. He replied that he had informed them that we were having pressurization problems and we would get back to him. I asked him if he had declared an emergency and he replied that he had not.

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Original NASA ASRS Text

Title: FLC OF A L1011, STOPPED CLB AT FL270 AND DONNED OXYGEN MASKS DUE TO A PRESSURIZATION PROB. ATC WAS NOTIFIED AND A NEW XPONDER CODE GIVEN TO MAKE AN EMER DSCNT. HOWEVER, THE SO OVERCAME THE PROB AND THE FLT CONTINUED AS NORMAL.

Narrative: DURING CLBOUT FROM MANCHESTER, ENGLAND, THE CABIN ALT WARNING HORN SOUNDED AS WE PASSED THROUGH FL270. I REMOVED MY BOOM MIKE/HEADSET WHILE DONNING MY OXYGEN MASK AND DID NOT HEAR A XMISSION THAT THE FO MADE TO LONDON CTL. WHEN I GOT BACK INTO THE COM LOOP, I HEARD LONDON ASKING WHAT THE NATURE OF OUR EMER WAS. I RESPONDED THAT WE WERE HAVING A PROB WITH THE PRESSURIZATION. THE CTLR THEN TOLD US TO SQUAWK 7700, WHICH I DID, AND CLRED US TO DSND TO FL240. BY THIS TIME THE SO HAD RESOLVED THE PROB AND I TOLD LONDON THAT WE DID NOT WANT TO DSND AND WOULD LIKE TO MAINTAIN OUR PRESENT ALT TO ENSURE THAT WE HAD IN FACT RESOLVED THE PROB. SHORTLY THEREAFTER I INFORMED LONDON CTL THAT WE DID HAVE EVERYTHING BACK TO NORMAL AND HE ASKED WHAT OUR INTENTIONS WERE. I TOLD HIM WE WANTED TO RESUME THE CLB TO FL310 AND REQUESTED CLRNC DIRECT TO 55N 10W, OUR OCEANIC ENTRY FIX. HE CLRED US AS REQUESTED AND SWITCHED US TO SCOTTISH CTL. SCOTTISH ASKED IF THE PAX OXYGEN MASKS HAD BEEN DEPLOYED AND I TOLD HIM THAT WE MANAGED TO AVOID THAT. I THEN ASKED SCOTTISH FOR A NEW XPONDER CODE WHICH HE SUPPLIED. AFTER EVERYTHING SETTLED, AND WE HAD THE FMS REPROGRAMMED WITH THE REVISED OCEANIC CLRNC WE RECEIVED JUST PRIOR TO THE PRESSURIZATION PROB, I BEGAN WONDERING WHAT HAD CAUSED LONDON CTL TO THINK WE WERE DECLARING AN EMER AND WANTED TO DSND. I ASKED THE FO WHAT HE HAD SAID TO LONDON WHILE I HAD MY HEADSET OFF. HE REPLIED THAT HE HAD INFORMED THEM THAT WE WERE HAVING PRESSURIZATION PROBS AND WE WOULD GET BACK TO HIM. I ASKED HIM IF HE HAD DECLARED AN EMER AND HE REPLIED THAT HE HAD NOT.

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.