EX900 flight crew loses cabin pressure at FL430; emergency declared; emergency descent executed.

Attributes
ACN	685961
Time
Date	200602
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 43000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	general aviation : corporate
Make Model Name	Falcon 900
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 135 flight time total : 16150 flight time type : 6625
ASRS Report	685961
Person 2
Affiliation	company : corporate
Function	flight attendant : on duty
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : cabin alt alert other flight crewa
Resolutory Action	controller : provided flight assist flight crew : landed as precaution flight crew : declared emergency flight crew : overcame equipment problem
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Slow loss of cabin pressure after leveling at FL430. Routine takeoff and climb to altitude. Initially FL400. Due to light chop; we requested a climb to FL430. After leveling; we noticed a cabin rate of climb at 600 FPM and passing 6000 ft cabin altitude. We requested a descent to FL380 and tried several other modes; including manual; to stop the climb but nothing worked. Center gave us FL290 but we had to declare an emergency to expedite the descent before the cabin exceeded 10000 ft. We descended via emergency descent checklist to 10000 ft MSL and then to 8000 ft. Cabin altitude reached 11000 ft. Masks deployed for passenger; but went back to 8000 ft and stabilized. No other incidents occurred. No passenger problems were experienced. Full time flight attendant was part of crew and was essential in handling cabin. Great asset for calming passenger concerns and covering safety items. It's company policy to have them on board for all flts. Still awaiting results from maintenance inspection and troubleshooting. Cabin pressure remained at 8.5 but we could never get control in any mode to drive outflow valves closed and drive cabin altitude down. Cpr aviation constantly fights to justify flight attendants but this case will certainly help our cause -- her efforts and coordination allowed us to concentrate on getting down quickly and not allowing fear or doubt to enter the passenger thoughts. Overall; I think it was handled well but we will review entire incident and get passenger feedback within the next business week.

Original NASA ASRS Text

Title: EX900 FLT CREW LOSES CABIN PRESSURE AT FL430; EMER DECLARED; EMER DSCNT EXECUTED.

Narrative: SLOW LOSS OF CABIN PRESSURE AFTER LEVELING AT FL430. ROUTINE TKOF AND CLB TO ALT. INITIALLY FL400. DUE TO LIGHT CHOP; WE REQUESTED A CLB TO FL430. AFTER LEVELING; WE NOTICED A CABIN RATE OF CLB AT 600 FPM AND PASSING 6000 FT CABIN ALT. WE REQUESTED A DSCNT TO FL380 AND TRIED SEVERAL OTHER MODES; INCLUDING MANUAL; TO STOP THE CLB BUT NOTHING WORKED. CTR GAVE US FL290 BUT WE HAD TO DECLARE AN EMER TO EXPEDITE THE DSCNT BEFORE THE CABIN EXCEEDED 10000 FT. WE DSNDED VIA EMER DSCNT CHKLIST TO 10000 FT MSL AND THEN TO 8000 FT. CABIN ALT REACHED 11000 FT. MASKS DEPLOYED FOR PAX; BUT WENT BACK TO 8000 FT AND STABILIZED. NO OTHER INCIDENTS OCCURRED. NO PAX PROBS WERE EXPERIENCED. FULL TIME FLT ATTENDANT WAS PART OF CREW AND WAS ESSENTIAL IN HANDLING CABIN. GREAT ASSET FOR CALMING PAX CONCERNS AND COVERING SAFETY ITEMS. IT'S COMPANY POLICY TO HAVE THEM ON BOARD FOR ALL FLTS. STILL AWAITING RESULTS FROM MAINT INSPECTION AND TROUBLESHOOTING. CABIN PRESSURE REMAINED AT 8.5 BUT WE COULD NEVER GET CTL IN ANY MODE TO DRIVE OUTFLOW VALVES CLOSED AND DRIVE CABIN ALT DOWN. CPR AVIATION CONSTANTLY FIGHTS TO JUSTIFY FLT ATTENDANTS BUT THIS CASE WILL CERTAINLY HELP OUR CAUSE -- HER EFFORTS AND COORD ALLOWED US TO CONCENTRATE ON GETTING DOWN QUICKLY AND NOT ALLOWING FEAR OR DOUBT TO ENTER THE PAX THOUGHTS. OVERALL; I THINK IT WAS HANDLED WELL BUT WE WILL REVIEW ENTIRE INCIDENT AND GET PAX FEEDBACK WITHIN THE NEXT BUSINESS WK.

Data retrieved from NASA's ASRS site as of January 2009 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.