B737 crew departs with bleed air switches off and gets cabin altitude warning at 10000 ft.

Attributes
ACN	720701
Time
Date	200612
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lga.airport
State Reference	NY
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : n90.tracon tracon : zzzz.tracon
Operator	common carrier : air carrier
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	720701
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	720706
Events
Anomaly	aircraft equipment problem : critical non adherence : company policies
Independent Detector	aircraft equipment other aircraft equipment : cabin alt warning horn
Resolutory Action	controller : issued new clearance
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Flight Crew Human Performance

Narrative:

On taxi-out from lga we had a taxi clearance change given while I was responding to the item 'packs and bleeds.' I glanced but did not verify the correct positions. On climb-out we smelled a peculiar odor but could not identify any problem. Departure control gave us clearance from 7000 ft to 12000 ft. When we climbed through 10000 ft we had the altitude warning horn sound. I asked ATC for an immediate return to 10000 ft for a pressurization problem. We donned our O2 masks and I reset the bleed switches. The cabin then started to descend and once it was below 9000 ft I told ATC we could continue our climb. I have heard of this similar scenario several times but always thought; 'it won't happen to me.' obviously; my mistake in trying to accomplish a checklist and taxi at a very busy airport.

Original NASA ASRS Text

Title: B737 CREW DEPARTS WITH BLEED AIR SWITCHES OFF AND GETS CABIN ALT WARNING AT 10000 FT.

Narrative: ON TAXI-OUT FROM LGA WE HAD A TAXI CLRNC CHANGE GIVEN WHILE I WAS RESPONDING TO THE ITEM 'PACKS AND BLEEDS.' I GLANCED BUT DID NOT VERIFY THE CORRECT POSITIONS. ON CLIMB-OUT WE SMELLED A PECULIAR ODOR BUT COULD NOT IDENTIFY ANY PROB. DEP CTL GAVE US CLRNC FROM 7000 FT TO 12000 FT. WHEN WE CLBED THROUGH 10000 FT WE HAD THE ALT WARNING HORN SOUND. I ASKED ATC FOR AN IMMEDIATE RETURN TO 10000 FT FOR A PRESSURIZATION PROB. WE DONNED OUR O2 MASKS AND I RESET THE BLEED SWITCHES. THE CABIN THEN STARTED TO DSND AND ONCE IT WAS BELOW 9000 FT I TOLD ATC WE COULD CONTINUE OUR CLB. I HAVE HEARD OF THIS SIMILAR SCENARIO SEVERAL TIMES BUT ALWAYS THOUGHT; 'IT WON'T HAPPEN TO ME.' OBVIOUSLY; MY MISTAKE IN TRYING TO ACCOMPLISH A CHKLIST AND TAXI AT A VERY BUSY ARPT.

Data retrieved from NASA's ASRS site as of January 2009 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.