Flight crew of a B737 returned and landed due to the lack of the aircraft starting to pressurize dur...

Attributes
ACN	272727
Time
Date	199405
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : las
State Reference	NV
Altitude	agl bound lower : 0 agl bound upper : 1200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : las
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : takeoff climbout : initial ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 200 flight time total : 9000 flight time type : 3000
ASRS Report	272727
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On the morning of may/xx/94 flight from las-lax, we were given a tight flow time for lax. I started the #2 engine and performed a single engine taxi. I directed the first officer to start the #1 engine and perform the after start flow. All checklists were completed and we were cleared for takeoff. Due to the cool morning, I did not notice that the packs were not operating and the aircraft was not pressurized on the ground. On the takeoff roll, I did notice the lack of air flow coming from the packs. At this point I knew the aircraft was not pressurized, but in the interest of safety, I continued the takeoff. We then returned to las for landing and proceeded to the gate for maintenance. Maintenance, the night before, had done some work in the east&east compartment. They, for some reason, disconnected a module for the packs. Maintenance never reinstalled the module. Also, there was not a logbook entry reflecting work done to the module.

Original NASA ASRS Text

Title: FLC OF A B737 RETURNED AND LANDED DUE TO THE LACK OF THE ACFT STARTING TO PRESSURIZE DURING TKOF.

Narrative: ON THE MORNING OF MAY/XX/94 FLT FROM LAS-LAX, WE WERE GIVEN A TIGHT FLOW TIME FOR LAX. I STARTED THE #2 ENG AND PERFORMED A SINGLE ENG TAXI. I DIRECTED THE FO TO START THE #1 ENG AND PERFORM THE AFTER START FLOW. ALL CHKLISTS WERE COMPLETED AND WE WERE CLRED FOR TKOF. DUE TO THE COOL MORNING, I DID NOT NOTICE THAT THE PACKS WERE NOT OPERATING AND THE ACFT WAS NOT PRESSURIZED ON THE GND. ON THE TKOF ROLL, I DID NOTICE THE LACK OF AIR FLOW COMING FROM THE PACKS. AT THIS POINT I KNEW THE ACFT WAS NOT PRESSURIZED, BUT IN THE INTEREST OF SAFETY, I CONTINUED THE TKOF. WE THEN RETURNED TO LAS FOR LNDG AND PROCEEDED TO THE GATE FOR MAINT. MAINT, THE NIGHT BEFORE, HAD DONE SOME WORK IN THE E&E COMPARTMENT. THEY, FOR SOME REASON, DISCONNECTED A MODULE FOR THE PACKS. MAINT NEVER REINSTALLED THE MODULE. ALSO, THERE WAS NOT A LOGBOOK ENTRY REFLECTING WORK DONE TO THE MODULE.

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 a B737 returned and landed due to the lack of the aircraft starting to pressurize during takeoff.