Flight crew of small transport cpr jet made an emergency descent after losing pressurization at 4100...

Attributes
ACN	282549
Time
Date	199409
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : tri
State Reference	TN
Altitude	msl bound lower : 41000 msl bound upper : 41000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl
Operator	general aviation : corporate
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 120 flight time total : 1200 flight time type : 10
ASRS Report	282549
Person 2
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 50 flight time total : 3009 flight time type : 150
ASRS Report	282548
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : declared emergency other other
Consequence	Other Other
Supplementary
Primary Problem	Aircraft

Narrative:

At 41000 ft a rapid decompression occurred, caused by a bad door seal. This caused an extremely loud and painful noise, sounding like a horn within the cabin. Cabin rate climbed rapidly, both pilot and copilot tried to don oxygen masks, but had difficulty getting sufficient oxygen, due to the mask frames. Due to the danger of becoming hypoxic, we initiated a dive to a safe altitude. Due to the mask problem radio communication was not possible, until a safe altitude was reached. Communication was then established with ZTL and the nature of the problem was explained. We then landed at tri- city tennessee. Supplemental information from acn 282548: the new masks would help in faster donning of the mask. In simulators they should reproduce the sound so as to help pilots recognize the noise/problem faster. The horn sound at 41000 ft is very incapacitating.

Original NASA ASRS Text

Title: FLC OF SMT CPR JET MADE AN EMER DSCNT AFTER LOSING PRESSURIZATION AT 41000 FT ALT.

Narrative: AT 41000 FT A RAPID DECOMPRESSION OCCURRED, CAUSED BY A BAD DOOR SEAL. THIS CAUSED AN EXTREMELY LOUD AND PAINFUL NOISE, SOUNDING LIKE A HORN WITHIN THE CABIN. CABIN RATE CLBED RAPIDLY, BOTH PLT AND COPLT TRIED TO DON OXYGEN MASKS, BUT HAD DIFFICULTY GETTING SUFFICIENT OXYGEN, DUE TO THE MASK FRAMES. DUE TO THE DANGER OF BECOMING HYPOXIC, WE INITIATED A DIVE TO A SAFE ALT. DUE TO THE MASK PROB RADIO COM WAS NOT POSSIBLE, UNTIL A SAFE ALT WAS REACHED. COM WAS THEN ESTABLISHED WITH ZTL AND THE NATURE OF THE PROB WAS EXPLAINED. WE THEN LANDED AT TRI- CITY TENNESSEE. SUPPLEMENTAL INFO FROM ACN 282548: THE NEW MASKS WOULD HELP IN FASTER DONNING OF THE MASK. IN SIMULATORS THEY SHOULD REPRODUCE THE SOUND SO AS TO HELP PLTS RECOGNIZE THE NOISE/PROB FASTER. THE HORN SOUND AT 41000 FT IS VERY INCAPACITATING.

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.

Flight crew of small transport cpr jet made an emergency descent after losing pressurization at 41000 ft altitude.