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|
Attributes | |
ACN | 1346745 |
Time | |
Date | 201604 |
Local Time Of Day | 0601-1200 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | Falcon 50 |
Operating Under FAR Part | Part 91 |
Flight Phase | Climb |
Flight Plan | IFR |
Person 1 | |
Function | Pilot Not Flying Captain |
Qualification | Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Flight Instructor |
Experience | Flight Crew Last 90 Days 165 Flight Crew Total 8800 Flight Crew Type 2000 |
Person 2 | |
Function | First Officer Pilot Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Experience | Flight Crew Last 90 Days 120 Flight Crew Total 7590 Flight Crew Type 2139 |
Events | |
Anomaly | Deviation - Procedural Published Material / Policy |
Narrative:
Maintenance was performed on the overhead panel to replace a broken fuel xfr pump switch. The work was accomplished overnight and the crew had a 12 hour overnight at home going from day 3 to day 4. The usual routine was followed and we departed on time. I was the designated PIC and PNF. What we missed before departure was that all 3 bleed air switches had been switched to the off position (apparently to accomplish the work on the overhead panel). During the after takeoff checklist the cabin rate and altitude did not look suspicious or alert me to the fact that we were not pressurizing. There was also no physiological issues noted in the climb that may have alerted us to an abnormal cabin situation - i.e. Ears popping; noises; etc. We were light on our way to our first pickup for the day so we had a good climb rate. As we approached FL230 we got the cabin master warning and the audible 'cabin cabin cabin' alert. At this time I noted the cabin altitude was right at the top of the yellow arc at 10000 feet. We stopped the climb; told ATC we had a pressurization issue and began a descent to 10000. The cabin continued to climb and the masks in the cabin dropped. As we descended and I ran the checklist; an item on the pressurization checklist had us check the position of the bleed air switches - and that is when we discovered that this was the source of the pressurization issue. I selected these switches to the automatic position and shortly thereafter we were able to regain control of the pressurization. Because the masks had dropped and we were close to ZZZ we elected to return and have maintenance reset the masks and continue our trip. There were multiple opportunities to discover that these switches were in the incorrect position. I'm not sure what maintenance procedures exist for resetting an aircraft after maintenance - but maybe these switches would have been caught if maintenance followed the preflight portion of our aircraft checklist? The sic could have caught the switches during the preflight and the PIC could have caught them during my normal scan / flow. The PIC (PNF) myself - in this case also noted that the pressurization seemed to be operating normally during the after takeoff checklist. Since these are switches we never touched (except in the sim) - I think it didn't stand out to us that they were in the wrong position. (Especially since we had just flown the aircraft 12 hours prior to this event) sitting in either seat in the cockpit it is also not very obvious that these switches are not in the normal position. Maybe something we could do in the future is when maintenance works on the overhead panel and has to change switch positions to accomplish work they could include in the write up in the aircraft logbook something like 'crew please verify correct switch positions on overhead panel'. That could add an extra layer to the process provide an opportunity to alert the crew to spend some extra time verifying that everything is in the correct position.
Original NASA ASRS Text
Title: Falcon 50 flight crew reported the cabin did not pressurize during climbout because the engine bleed air switches were off. They selected switches to AUTO and regained pressurization. Crew returned to departure airport to have O2 masks reset.
Narrative: Maintenance was performed on the overhead panel to replace a broken fuel XFR pump switch. The work was accomplished overnight and the crew had a 12 hour overnight at home going from day 3 to day 4. The usual routine was followed and we departed on time. I was the designated PIC and PNF. What we missed before departure was that all 3 Bleed Air switches had been switched to the OFF position (apparently to accomplish the work on the overhead panel). During the after takeoff checklist the cabin rate and altitude did not look suspicious or alert me to the fact that we were not pressurizing. There was also no physiological issues noted in the climb that may have alerted us to an abnormal cabin situation - i.e. ears popping; noises; etc. We were light on our way to our first pickup for the day so we had a good climb rate. As we approached FL230 we got the CABIN master warning and the audible 'cabin cabin cabin' alert. At this time I noted the cabin altitude was right at the top of the yellow arc at 10000 feet. We stopped the climb; told ATC we had a pressurization issue and began a descent to 10000. The cabin continued to climb and the masks in the cabin dropped. As we descended and I ran the checklist; an item on the pressurization checklist had us check the position of the Bleed Air switches - and that is when we discovered that this was the source of the pressurization issue. I selected these switches to the AUTO position and shortly thereafter we were able to regain control of the pressurization. Because the masks had dropped and we were close to ZZZ we elected to return and have maintenance reset the masks and continue our trip. There were multiple opportunities to discover that these switches were in the incorrect position. I'm not sure what maintenance procedures exist for resetting an aircraft after maintenance - but maybe these switches would have been caught if maintenance followed the preflight portion of our aircraft checklist? The SIC could have caught the switches during the preflight and the PIC could have caught them during my normal scan / flow. The PIC (PNF) myself - in this case also noted that the pressurization seemed to be operating normally during the after takeoff checklist. Since these are switches we never touched (except in the SIM) - I think it didn't stand out to us that they were in the wrong position. (Especially since we had just flown the aircraft 12 hours prior to this event) Sitting in either seat in the cockpit it is also not very obvious that these switches are not in the normal position. Maybe something we could do in the future is when maintenance works on the overhead panel and has to change switch positions to accomplish work they could include in the write up in the aircraft logbook something like 'CREW PLEASE VERIFY CORRECT SWITCH POSITIONS ON OVERHEAD PANEL'. That could add an extra layer to the process provide an opportunity to alert the crew to spend some extra time verifying that everything is in the correct position.
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.