L329 crew had cabin depressurization.

Attributes
ACN	448980
Time
Date	199909
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : zme.artcc
State Reference	TN
Altitude	msl single value : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme.artcc
Operator	general aviation : corporate
Make Model Name	Jetstar 1329 (C140)
Operating Under FAR Part	Part 91
Flight Plan	IFR
Aircraft 2
Flight Phase	cruise : level
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 50 flight time total : 14300 flight time type : 4000
ASRS Report	448980
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : published procedure
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Aircraft

Narrative:

Climbing through FL350, the 'cabin pressure low' annunciator light came on, followed by 'duct pressure/high low' light illuminating. Immediately checking all system switches in correct position and calling for checklist. Going through checklist, the oxygen masks deployed. The crew had quick donning mask already out, and immediately secured on. At this point I asked for a lower altitude. ATC gave it to me. There was no rapid decompression. The cabin was holding pressure and indicating 1200-1400 ft. The passenger had mask on. I continued to descend to below 14000 ft and used ram air. I asked to return to home base, ZZZ field. At no time was there any critical events, with the exception of immediately descending. The passenger did not have any problems, the oxygen mask deployed as advertised. The incoming air was somehow slowed, or stopped, to allow the pressurization to hold. We are investigating the problem with the pressurization system at this time.

Original NASA ASRS Text

Title: L329 CREW HAD CABIN DEPRESSURIZATION.

Narrative: CLBING THROUGH FL350, THE 'CABIN PRESSURE LOW' ANNUNCIATOR LIGHT CAME ON, FOLLOWED BY 'DUCT PRESSURE/HIGH LOW' LIGHT ILLUMINATING. IMMEDIATELY CHKING ALL SYS SWITCHES IN CORRECT POS AND CALLING FOR CHKLIST. GOING THROUGH CHKLIST, THE OXYGEN MASKS DEPLOYED. THE CREW HAD QUICK DONNING MASK ALREADY OUT, AND IMMEDIATELY SECURED ON. AT THIS POINT I ASKED FOR A LOWER ALT. ATC GAVE IT TO ME. THERE WAS NO RAPID DECOMPRESSION. THE CABIN WAS HOLDING PRESSURE AND INDICATING 1200-1400 FT. THE PAX HAD MASK ON. I CONTINUED TO DSND TO BELOW 14000 FT AND USED RAM AIR. I ASKED TO RETURN TO HOME BASE, ZZZ FIELD. AT NO TIME WAS THERE ANY CRITICAL EVENTS, WITH THE EXCEPTION OF IMMEDIATELY DSNDING. THE PAX DID NOT HAVE ANY PROBS, THE OXYGEN MASK DEPLOYED AS ADVERTISED. THE INCOMING AIR WAS SOMEHOW SLOWED, OR STOPPED, TO ALLOW THE PRESSURIZATION TO HOLD. WE ARE INVESTIGATING THE PROB WITH THE PRESSURIZATION SYS AT THIS TIME.

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.