Narrative:

Departed runway; VMC climb clearance; maximum takeoff power (mtop) and bleeds off for performance due to weight. Complicated procedure requiring a lot of attention and precision flying. Forgot to turn bleeds on. At approximately 9;500 feet master warning cabin pressure warning illuminated. Donned mask and immediately turned on bleeds. Called for the checklist to cover all bases even though I knew we got the warning because the bleeds were off. While going through the checklist we noticed that the cabin was remaining at a steady 9;500 feet pressure altitude and would not pressurize. As a result the cabin press warning light remained illuminated. Completed cabin pressure checklist which directed us to the pressurization fail checklist. The pressurization fail checklist eventually had us switch the pressurization mode to manual. Once in manual mode we were finally able to control the cabin pressure. We decreased the cabin altitude and the cabin pressure warning light extinguished. Not sure why it would not pressurize in auto mode. Completed the manual pressurization control checklist. Once pressurization was normalized removed O2 masks; climbed up to altitude and continued our flight as normal. Once stabilized in cruise called maintenance control and advised them about what happened.[the cause was] workload saturation and distractions like the gear warning horn going off non-stop and flying close to terrain. Malfunction of the pressurization auto mode.

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Original NASA ASRS Text

Title: Q400 Captain reported experiencing loss of cabin pressure resulting from flight crew failure to turn engine bleed switches on following a special takeoff procedure. Recovery from this error was compounded by malfunction of the pressurization auto mode.

Narrative: Departed runway; VMC climb clearance; Maximum Takeoff Power (MTOP) and bleeds off for performance due to weight. Complicated procedure requiring a lot of attention and precision flying. Forgot to turn bleeds on. At approximately 9;500 feet master warning cabin pressure warning illuminated. Donned mask and immediately turned on bleeds. Called for the checklist to cover all bases even though I knew we got the warning because the bleeds were off. While going through the checklist we noticed that the cabin was remaining at a steady 9;500 feet pressure altitude and would not pressurize. As a result the cabin press warning light remained illuminated. Completed cabin pressure checklist which directed us to the pressurization fail checklist. The pressurization fail checklist eventually had us switch the pressurization mode to Manual. Once in Manual mode we were finally able to control the cabin pressure. We decreased the cabin altitude and the cabin pressure warning light extinguished. Not sure why it would not pressurize in Auto mode. Completed the manual pressurization control checklist. Once pressurization was normalized removed O2 masks; climbed up to altitude and continued our flight as normal. Once stabilized in cruise called Maintenance Control and advised them about what happened.[The cause was] workload saturation and distractions like the gear warning horn going off non-stop and flying close to terrain. Malfunction of the pressurization Auto mode.

Data retrieved from NASA's ASRS site 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.