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|
Attributes | |
ACN | 1688652 |
Time | |
Date | 201910 |
Local Time Of Day | 1201-1800 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | TBM 900 / TBM 930 |
Operating Under FAR Part | Part 91 |
Flight Phase | Cruise |
Route In Use | Direct |
Flight Plan | IFR |
Component | |
Aircraft Component | Pressurization System |
Person 1 | |
Function | Single Pilot |
Qualification | Flight Crew Commercial Flight Crew Instrument Flight Crew Multiengine |
Experience | Flight Crew Last 90 Days 42 Flight Crew Total 2005 Flight Crew Type 371 |
Events | |
Anomaly | Aircraft Equipment Problem Critical Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy Deviation - Track / Heading All Types Inflight Event / Encounter Weather / Turbulence |
Narrative:
I was transitioning a frontal zone with thunderstorm activity both south and north of my flight path at FL300. From my flight planning before takeoff; it was clear that I would have to transit the frontal zone and a center weather advisory area for convective activity (two sigmets were subsequently declared). I departed with a plan to approach the front on its southeast side and assess whether there was a practical route through the zone or divert.once at cruise and assessing the big picture via nexrad uplink to the tbm G1000 nxi; I amended my flight plan to head to the ZZZ VOR. Using on board radar as well as the uploaded weather products from xm weather data; there was a viable route across the frontal zone from about 50 miles southwest of ZZZ VOR to ZZZ1 VOR. I made the decision to continue after continuing approximately 50 miles southwest of ZZZ before turning direct to ZZZ1. ATC cleared me as requested with approved deviations for weather as required.I was in IMC at FL300 about 75 miles west of ZZZ and was clear of precipitation; no turbulence and negative returns on both short and longer range on-board radar using tilt to evaluate the weather. As I scanned the mfd showing engine and environmental data; I saw cabin altitude has climbed from 9;600 ft. (Normal for a tbm at FL310) to above 10;500 and the indicator began to flash red.I knew from training (initial and recurrent) that I had a pressurization issue and immediately reached for the pilot oxygen mask (zodiac; quick donning) - at the same time asking center initially for a descent to FL290 and when they didn't immediately respond; saying 'denver center; aircraft X needs to descend now!'. As I released the mask from storage; the alert system on the aircraft audio annunciator gave a warning 'cabin altitude - use oxygen' just as the cas display on the mfd showed the same written messages.the TBM910 is equipped with an edm (emergency descent mode) that is triggered by the cabin altitude warning - it is designed to turn the aircraft 90 degrees from its current course and command an expedited descent at vmo to 15;000 ft. MSL and then level out. As I working to don the mask; the edm triggered and immediately began an expedited descent. Seeing the cabin altitude climbing through 11;500' my priority was donning the mask - a process that required removing my headset and glasses; getting the mask seated; glasses and headset back in place. While I had been trained in the procedure; this was the first time in an emergency and between adrenaline and process; it took 30 seconds plus to get my mask in place.by this time; the edm was well into the turn and the aircraft was descending at 4000+ fpm - seeing the aircraft now turning left; towards weather I had deviated around shortly before; and on oxygen; I overrode the edm by a double click on the autopilot disconnect; retarded the power level and began rolling the wings level and a gently pull out to level off at FL240.I re-established communication with center and advised that I had lost pressurization and was on oxygen. Center asked if I was [requesting priority handling]; I responded with 'standby' as I was working to hand fly the aircraft; turn back away from the weather and 'collect my wits.' I advised center I was level at FL240 and back direct to ZZZ VOR.I cautiously re-enabled the autopilot; verified its operation and ran the emergency check list for a the pressurization loss. The checklist called for the pressurization system to be reset by turning the bleed control from on; to off/rst; then back to on. I did this and saw that the cabin was beginning to re-pressurize.center asked me if I wanted to land at ZZZ2. I advised that I had reset the pressurization system; and would advise. The cabin altitude descended to 7;000 ft.; nominal for the aircraft at FL240 and was stable. I advised center that I would continue to ZZZ1 but if another event occurred (now with oxygen mask at hand and clear of weather) I would land at the nearest airport. I continued the flight to and landed without further incident.reviewing the situation; I have the following observations:1. My training established the criticality of getting on oxygen when faced with a pressurization loss. This I did.2. My training in aircraft or simulator had not required donning the mask while flying the aircraft. A not so obvious procedural lesson; now learned. Practicing on the ground is simply not the same.3. I was task consumed - I should have [advised ATC]. My sincere thanks to center for their awareness of the situation and providing me with the time to think!4. Should I have diverted after the event or not? I assessed the situation; reset the pressurization while on oxygen and with capacity good for at least 90+ minute (just me in the plane). Seeing the pressure maintained; I thought through what I would do if the situation reoccurred. I flew the rest of the flight with my eyes always scanning the cabin altitude and rate of climb indicators. Clearly; if I had not regained pressurization; I would have landed as soon as practical. With pressurization restored; substantial fuel more than adequate to complete the flight with required reserves; a back up plan already in mind and oxygen mask on my lap; I believe this was a rational analysis and decision.5. Continuing to ZZZ1? I knew the weather and winds were in my favor - both thanks to pre-flight planning and uplinked weather (metar/taf). Between weather and long runways; I had chosen my destination before leaving. It was a known and verified factor.I am grateful to my instructor and simulator trainers - the training stuck and with the exception of donning the oxygen mask; I believe I executed recovery as trained. Writing this report has helped me evaluate my performance handling the event; please excuse the lack of brevity! From FL300 to FL240 and level out was a little over 1 minute and 45 seconds; turns out that is really a long time!
Original NASA ASRS Text
Title: TBM-910 pilot reported a pressurization problem that required an expedited descent.
Narrative: I was transitioning a frontal zone with thunderstorm activity both south and north of my flight path at FL300. From my flight planning before takeoff; it was clear that I would have to transit the frontal zone and a center weather advisory area for convective activity (two SIGMETS were subsequently declared). I departed with a plan to approach the front on its SE side and assess whether there was a practical route through the zone or divert.Once at cruise and assessing the big picture via NEXRAD uplink to the TBM G1000 Nxi; I amended my flight plan to head to the ZZZ VOR. Using on board radar as well as the uploaded weather products from XM Weather data; there was a viable route across the frontal zone from about 50 miles southwest of ZZZ VOR to ZZZ1 VOR. I made the decision to continue after continuing approximately 50 miles southwest of ZZZ before turning direct to ZZZ1. ATC cleared me as requested with approved deviations for weather as required.I was in IMC at FL300 about 75 miles west of ZZZ and was clear of precipitation; no turbulence and negative returns on both short and longer range on-board radar using tilt to evaluate the weather. As I scanned the MFD showing engine and environmental data; I saw cabin altitude has climbed from 9;600 ft. (normal for a TBM at FL310) to above 10;500 and the indicator began to flash red.I knew from training (initial and recurrent) that I had a pressurization issue and immediately reached for the Pilot oxygen mask (Zodiac; quick donning) - at the same time asking Center initially for a descent to FL290 and when they didn't immediately respond; saying 'Denver Center; Aircraft X needs to descend NOW!'. As I released the mask from storage; the alert system on the aircraft audio annunciator gave a Warning 'Cabin Altitude - Use Oxygen' just as the CAS display on the MFD showed the same written messages.The TBM910 is equipped with an EDM (Emergency Descent Mode) that is triggered by the cabin altitude warning - it is designed to turn the aircraft 90 degrees from its current course and command an expedited descent at VMO to 15;000 ft. MSL and then level out. As I working to don the mask; the EDM triggered and immediately began an expedited descent. Seeing the cabin altitude climbing through 11;500' my priority was donning the mask - a process that required removing my headset and glasses; getting the mask seated; glasses and headset back in place. While I had been trained in the procedure; this was the first time in an emergency and between adrenaline and process; it took 30 seconds plus to get my mask in place.By this time; the EDM was well into the turn and the aircraft was descending at 4000+ fpm - seeing the aircraft now turning left; towards weather I had deviated around shortly before; and on Oxygen; I overrode the EDM by a double click on the Autopilot disconnect; retarded the power level and began rolling the wings level and a gently pull out to level off at FL240.I re-established communication with Center and advised that I had lost pressurization and was on Oxygen. Center asked if I was [requesting priority handling]; I responded with 'Standby' as I was working to hand fly the aircraft; turn back away from the weather and 'collect my wits.' I advised Center I was level at FL240 and back direct to ZZZ VOR.I cautiously re-enabled the autopilot; verified its operation and ran the emergency check list for a the pressurization loss. The checklist called for the pressurization system to be reset by turning the BLEED control from ON; to OFF/RST; then back to ON. I did this and saw that the cabin was beginning to re-pressurize.Center asked me if I wanted to land at ZZZ2. I advised that I had reset the pressurization system; and would advise. The cabin altitude descended to 7;000 ft.; nominal for the aircraft at FL240 and was stable. I advised Center that I would continue to ZZZ1 but if another event occurred (now with oxygen mask at hand and clear of weather) I would land at the nearest airport. I continued the flight to and landed without further incident.Reviewing the situation; I have the following observations:1. My training established the criticality of getting on oxygen when faced with a pressurization loss. This I did.2. My training in aircraft or simulator had not required donning the mask while flying the aircraft. A not so obvious procedural lesson; now learned. Practicing on the ground is simply not the same.3. I was task consumed - I should have [advised ATC]. My sincere thanks to Center for their awareness of the situation and providing me with the time to THINK!4. Should I have diverted after the event or not? I assessed the situation; reset the pressurization while on oxygen and with capacity good for at least 90+ minute (just me in the plane). Seeing the pressure maintained; I thought through what I would do if the situation reoccurred. I flew the rest of the flight with my eyes always scanning the cabin altitude and rate of climb indicators. Clearly; if I had not regained pressurization; I would have landed as soon as practical. With pressurization restored; substantial fuel more than adequate to complete the flight with required reserves; a back up plan already in mind and oxygen mask on my lap; I believe this was a rational analysis and decision.5. Continuing to ZZZ1? I knew the weather and winds were in my favor - both thanks to pre-flight planning and uplinked weather (METAR/TAF). Between weather and long runways; I had chosen my destination before leaving. It was a known and verified factor.I am grateful to my instructor and simulator trainers - the training stuck and with the exception of donning the oxygen mask; I believe I executed recovery as trained. Writing this report has helped me evaluate my performance handling the event; please excuse the lack of brevity! From FL300 to FL240 and level out was a little over 1 minute and 45 seconds; turns out that is really a long time!
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.