 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
CL604 captain made an emergency descent due to cabin altitude warning and adjusting press via manual had no affect. However, after descending to an acceptable altitude, the captain remembered he had shut off both engine packs on the ground due to exhaust ingestion, but had not turned them back on.
| Attributes | |
| ACN | 533788 |
| Time | |
| Date | 200112 |
| Day | Sun |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : zob.artcc |
| State Reference | OH |
| Altitude | msl single value : 23000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zob.artcc |
| Operator | general aviation : corporate |
| Make Model Name | Challenger CL604 |
| Operating Under FAR Part | Part 91 |
| Navigation In Use | other |
| Flight Phase | climbout : intermediate altitude |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : charter |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 50 flight time total : 5000 flight time type : 1200 |
| ASRS Report | 533788 |
| Person 2 | |
| Affiliation | company : corporate |
| Function | flight crew : first officer |
| Events | |
| Anomaly | aircraft equipment problem : critical non adherence : published procedure |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : declared emergency flight crew : overcame equipment problem |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Aircraft |
| Primary Problem | Flight Crew Human Performance |
Narrative:
Turned packs off on ground due to exhaust ingestion. Forgot to turn on prior to takeoff. Climb check performed by me (captain PNF) appeared normal. At FL230 or so the cabin altitude caution occurred and we requested descent and donned masks prematurely anticipating emergency situation. Cabin altitude warning occurred and we performed memory checklist and began more rapid descent, deployed passenger O2. I retrieved emergency check and attempted a manual control of pressurization. At that point I realized the packs were off. I turned packs on and aircraft regained normal control. What I feel I did wrong other than the obvious forgetting packs on: could have recognized an abnormal (yet still indicating green) cabin altitude during climb check. Could have checked packs on during climb check call of 'pressurization on check.' could have initiated the abnormal cabin altitude check as soon as it occurred (which incorporates a check of packs) rather than begin in descent and begin preparing for the emergency which had not yet occurred. Emergency check does not consider troubleshooting, only escaping a potentially dangerous situation.
Original NASA ASRS Text
Title: CL604 CAPT MADE AN EMER DESCENT DUE TO CABIN ALT WARNING AND ADJUSTING PRESS VIA MANUAL HAD NO AFFECT. HOWEVER, AFTER DESCENDING TO AN ACCEPTABLE ALT, THE CAPT REMEMBERED HE HAD SHUT OFF BOTH ENGINE PACKS ON THE GND DUE TO EXHAUST INGESTION, BUT HAD NOT TURNED THEM BACK ON.
Narrative: TURNED PACKS OFF ON GND DUE TO EXHAUST INGESTION. FORGOT TO TURN ON PRIOR TO TKOF. CLIMB CHK PERFORMED BY ME (CAPT PNF) APPEARED NORMAL. AT FL230 OR SO THE CABIN ALT CAUTION OCCURRED AND WE REQUESTED DESCENT AND DONNED MASKS PREMATURELY ANTICIPATING EMER SIT. CABIN ALT WARNING OCCURRED AND WE PERFORMED MEMORY CHKLIST AND BEGAN MORE RAPID DESCENT, DEPLOYED PAX O2. I RETRIEVED EMER CHK AND ATTEMPTED A MANUAL CTL OF PRESSURIZATION. AT THAT POINT I REALIZED THE PACKS WERE OFF. I TURNED PACKS ON AND ACFT REGAINED NORMAL CTL. WHAT I FEEL I DID WRONG OTHER THAN THE OBVIOUS FORGETTING PACKS ON: COULD HAVE RECOGNIZED AN ABNORMAL (YET STILL INDICATING GREEN) CABIN ALT DURING CLIMB CHK. COULD HAVE CHECKED PACKS ON DURING CLIMB CHK CALL OF 'PRESSURIZATION ON CHK.' COULD HAVE INITIATED THE ABNORMAL CABIN ALT CHECK AS SOON AS IT OCCURRED (WHICH INCORPORATES A CHK OF PACKS) RATHER THAN BEGIN IN DESCENT AND BEGIN PREPARING FOR THE EMER WHICH HAD NOT YET OCCURRED. EMER CHK DOES NOT CONSIDER TROUBLESHOOTING, ONLY ESCAPING A POTENTIALLY DANGEROUS SIT.
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.