Narrative:

After takeoff from okc climbing through 10000 ft to an altitude of 16000 ft, I noticed that the cabin pressure altitude was climbing rapidly and approaching the ambient altitude of the aircraft. I notified center that we had to level and we had a possible problem. We were assigned 13000 ft and the copilot, who was flying, leveled the aircraft at 13000 ft. I continued to monitor the pressure altitude of the cabin and determined that we had lost pressurization. I tried to tell the center controller we needed lower and instructed the copilot to start a descent. Simultaneously I selected manual control of the pressurization and attempted to decrease the cabin altitude which was almost at 13000 ft. I regained control of the cabin and notified center as such and asked what altitude they wanted us at. Center said we better be at 13000 ft. When the copilot noted that the pressurization problem was solved, he had leveled at 12000 ft. I told the copilot to climb, but he was slow to react and somewhat unsure of what to do since he had missed the controller's instruction. During this event, I was overloaded by having to talk to center, control the pressurization in manual and communicate with the copilot. In hindsight, an emergency should have been declared earlier to allow the controller time to react.

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Original NASA ASRS Text

Title: MLG HAS PRESSURIZATION PROB, MAKES DSCNT PRIOR TO NOTIFYING ATC.

Narrative: AFTER TKOF FROM OKC CLBING THROUGH 10000 FT TO AN ALT OF 16000 FT, I NOTICED THAT THE CABIN PRESSURE ALT WAS CLBING RAPIDLY AND APCHING THE AMBIENT ALT OF THE ACFT. I NOTIFIED CTR THAT WE HAD TO LEVEL AND WE HAD A POSSIBLE PROB. WE WERE ASSIGNED 13000 FT AND THE COPLT, WHO WAS FLYING, LEVELED THE ACFT AT 13000 FT. I CONTINUED TO MONITOR THE PRESSURE ALT OF THE CABIN AND DETERMINED THAT WE HAD LOST PRESSURIZATION. I TRIED TO TELL THE CTR CTLR WE NEEDED LOWER AND INSTRUCTED THE COPLT TO START A DSCNT. SIMULTANEOUSLY I SELECTED MANUAL CTL OF THE PRESSURIZATION AND ATTEMPTED TO DECREASE THE CABIN ALT WHICH WAS ALMOST AT 13000 FT. I REGAINED CTL OF THE CABIN AND NOTIFIED CTR AS SUCH AND ASKED WHAT ALT THEY WANTED US AT. CTR SAID WE BETTER BE AT 13000 FT. WHEN THE COPLT NOTED THAT THE PRESSURIZATION PROB WAS SOLVED, HE HAD LEVELED AT 12000 FT. I TOLD THE COPLT TO CLB, BUT HE WAS SLOW TO REACT AND SOMEWHAT UNSURE OF WHAT TO DO SINCE HE HAD MISSED THE CTLR'S INSTRUCTION. DURING THIS EVENT, I WAS OVERLOADED BY HAVING TO TALK TO CTR, CTL THE PRESSURIZATION IN MANUAL AND COMMUNICATE WITH THE COPLT. IN HINDSIGHT, AN EMER SHOULD HAVE BEEN DECLARED EARLIER TO ALLOW THE CTLR TIME TO REACT.

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.