Narrative:

While on initial climb out; we were level at 4;000 ft and the aircraft started to depressurize. Looking at the cabin pressure control panel we noticed a cabin rate in excess of -2;000 ft/minute and a differential reaching 5.2 max. A captain was deadheading on our flight and called the aircraft cockpit through the flight attendant phone to see what was happening and if he could help. He let us know passengers were in a lot of pain. Since we could not get the cabin pressure under control and we had passengers in pain I decided to do an air return. Upon landing we discovered the pressurization dump valve circuit breaker had popped.

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Original NASA ASRS Text

Title: Level at 4;000 FT after takeoff; an SF340 Captain experiences pressurization anomalies causing ear pain in the passengers. The crew elects to return to the departure airport where the Dump Valve Circuit Breaker is found to be tripped.

Narrative: While on initial climb out; we were level at 4;000 FT and the aircraft started to depressurize. Looking at the cabin pressure control panel we noticed a cabin rate in excess of -2;000 FT/minute and a differential reaching 5.2 max. A Captain was deadheading on our flight and called the aircraft cockpit through the flight attendant phone to see what was happening and if he could help. He let us know passengers were in a lot of pain. Since we could not get the cabin pressure under control and we had passengers in pain I decided to do an air return. Upon landing we discovered the pressurization Dump Valve Circuit Breaker had popped.

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.