A B757 aircraft flying in ZDV airspace experiences a rapid loss of pressurization. During this loss ...

Attributes
ACN	378960
Time
Date	199707
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zdv
State Reference	CO
Aircraft 1
Controlling Facilities	artcc : zdv tower : dtw
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	378960
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
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 none taken : unable
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

The event occurred more than 6 weeks ago prior to vacation so some minor details are difficult to recall. For a more detailed description refer to captain's report which I have read and made my inputs into. The aircraft logbook also contains a detailed description of the indications leading up to and immediately after the rapid depressurization. The only salient point of interest to add is that after performing the explosive and rapid descent checklists, I was very concerned about the electrical overheat smell both in the cockpit and reported by the flight attendants. This combined with the seemingly unrelated system problems led me to suspect a possibly more serious problem such as an overheat or fire. The system problems have since been sorted out and the relationships explained and the electrical smell turned out to be the dust on the oxygen generators heating up. I have discussed this with many of my airline pilot friends from air carrier and other airlines and some were aware of the potential smoky smell but most were not. While I realize that we don't want to encourage any crews to dismiss a potential fire, a note in the rapid descent checklist or the preamble to the emergency section about the smell associated with deploying the masks might relay some extraneous concerns.

Original NASA ASRS Text

Title: A B757 ACFT FLYING IN ZDV AIRSPACE EXPERIENCES A RAPID LOSS OF PRESSURIZATION. DURING THIS LOSS OF PRESSURE AND THE ACFT DSNDING TO A LOWER ALT, AN ODOR IS DETECTED THAT MAKES THE FLC THINK A FIRE COULD BE HAPPENING.

Narrative: THE EVENT OCCURRED MORE THAN 6 WKS AGO PRIOR TO VACATION SO SOME MINOR DETAILS ARE DIFFICULT TO RECALL. FOR A MORE DETAILED DESCRIPTION REFER TO CAPT'S RPT WHICH I HAVE READ AND MADE MY INPUTS INTO. THE ACFT LOGBOOK ALSO CONTAINS A DETAILED DESCRIPTION OF THE INDICATIONS LEADING UP TO AND IMMEDIATELY AFTER THE RAPID DEPRESSURIZATION. THE ONLY SALIENT POINT OF INTEREST TO ADD IS THAT AFTER PERFORMING THE EXPLOSIVE AND RAPID DSCNT CHKLISTS, I WAS VERY CONCERNED ABOUT THE ELECTRICAL OVERHEAT SMELL BOTH IN THE COCKPIT AND RPTED BY THE FLT ATTENDANTS. THIS COMBINED WITH THE SEEMINGLY UNRELATED SYS PROBS LED ME TO SUSPECT A POSSIBLY MORE SERIOUS PROB SUCH AS AN OVERHEAT OR FIRE. THE SYS PROBS HAVE SINCE BEEN SORTED OUT AND THE RELATIONSHIPS EXPLAINED AND THE ELECTRICAL SMELL TURNED OUT TO BE THE DUST ON THE OXYGEN GENERATORS HEATING UP. I HAVE DISCUSSED THIS WITH MANY OF MY AIRLINE PLT FRIENDS FROM ACR AND OTHER AIRLINES AND SOME WERE AWARE OF THE POTENTIAL SMOKY SMELL BUT MOST WERE NOT. WHILE I REALIZE THAT WE DON'T WANT TO ENCOURAGE ANY CREWS TO DISMISS A POTENTIAL FIRE, A NOTE IN THE RAPID DSCNT CHKLIST OR THE PREAMBLE TO THE EMER SECTION ABOUT THE SMELL ASSOCIATED WITH DEPLOYING THE MASKS MIGHT RELAY SOME EXTRANEOUS CONCERNS.

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.

A B757 aircraft flying in ZDV airspace experiences a rapid loss of pressurization. During this loss of pressure and the aircraft descending to a lower altitude, an odor is detected that makes the flight crew think a fire could be happening.