Cpr pilot executes emergency descent.

Attributes
ACN	448319
Time
Date	199909
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : csn.vortac
State Reference	VA
Altitude	msl bound lower : 23000 msl bound upper : 37000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zdc.artcc
Operator	general aviation : corporate
Make Model Name	Citation II S2/Bravo
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	cruise : level
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 50 flight time total : 20000 flight time type : 3700
ASRS Report	448319
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	aircraft equipment problem : critical altitude deviation : excursion from assigned altitude other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance controller : provided flight assist flight crew : declared emergency flight crew : diverted to another airport
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Flight was FL370. All was normal till near casanova VOR. Then cabin began rapid climb. Went to emergency checklist, could not halt rise. Called ZDV but got no reply. ZDC said they could hear microphone keying but no audio. Started emergency descent, turned left away from casanova VOR, stopped descent at FL230. Called ZDC on other microphone and got good communication. Got clearance to land at dulles, was in VFR conditions on descent with good visibility. Human performance: think I used good judgement and took correct action. The only thing not prepared for was all the noise. The only thing not done in emergency was to put transponder on 7700.

Original NASA ASRS Text

Title: CPR PLT EXECUTES EMER DSCNT.

Narrative: FLT WAS FL370. ALL WAS NORMAL TILL NEAR CASANOVA VOR. THEN CABIN BEGAN RAPID CLB. WENT TO EMER CHKLIST, COULD NOT HALT RISE. CALLED ZDV BUT GOT NO REPLY. ZDC SAID THEY COULD HEAR MIKE KEYING BUT NO AUDIO. STARTED EMER DSCNT, TURNED L AWAY FROM CASANOVA VOR, STOPPED DSCNT AT FL230. CALLED ZDC ON OTHER MIKE AND GOT GOOD COM. GOT CLRNC TO LAND AT DULLES, WAS IN VFR CONDITIONS ON DSCNT WITH GOOD VISIBILITY. HUMAN PERFORMANCE: THINK I USED GOOD JUDGEMENT AND TOOK CORRECT ACTION. THE ONLY THING NOT PREPARED FOR WAS ALL THE NOISE. THE ONLY THING NOT DONE IN EMER WAS TO PUT XPONDER ON 7700.

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.