Lear 60 flight crew neglects to turn cabin air switch on prior to departure.

Attributes
ACN	699025
Time
Date	200606
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : zbw.artcc
State Reference	NH
Altitude	msl single value : 16000
Environment
Flight Conditions	Mixed
Weather Elements	Rain Fog Thunderstorm
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zbw.artcc
Operator	general aviation : corporate
Make Model Name	Learjet 60
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	climbout : initial
Route In Use	enroute airway : v489.airway
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 13800 flight time type : 1800
ASRS Report	699025
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe non adherence : far non adherence : company policies other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : cabin press warning other flight crewa other flight crewb
Resolutory Action	flight crew : overcame equipment problem
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Flight Crew Human Performance

Narrative:

The cabin air switch was not turned on prior to takeoff. This omission wasn't caught until the 'pressurization system' caution illuminated at 8000 ca. An immediate descent to 10000 ft was requested while the crew re-pressurized the cabin. Luckily enough this was a low altitude trip and the cabin never climbed about 9500 ca. Contributing factors: 1) poor design on learjet pressurization system. The cabin air switch must be turned on prior to departure unlike most other aircraft types. Forgetting this switch is a common mistake (especially if distraction) even with experienced lear crews. 2) distrs: WX; trip route changes; radio calls; and traffic. 3) tired crew.

Original NASA ASRS Text

Title: LEAR 60 FLT CREW NEGLECTS TO TURN CABIN AIR SWITCH ON PRIOR TO DEP.

Narrative: THE CABIN AIR SWITCH WAS NOT TURNED ON PRIOR TO TKOF. THIS OMISSION WASN'T CAUGHT UNTIL THE 'PRESSURIZATION SYS' CAUTION ILLUMINATED AT 8000 CA. AN IMMEDIATE DSCNT TO 10000 FT WAS REQUESTED WHILE THE CREW RE-PRESSURIZED THE CABIN. LUCKILY ENOUGH THIS WAS A LOW ALT TRIP AND THE CABIN NEVER CLBED ABOUT 9500 CA. CONTRIBUTING FACTORS: 1) POOR DESIGN ON LEARJET PRESSURIZATION SYS. THE CABIN AIR SWITCH MUST BE TURNED ON PRIOR TO DEP UNLIKE MOST OTHER ACFT TYPES. FORGETTING THIS SWITCH IS A COMMON MISTAKE (ESPECIALLY IF DISTR) EVEN WITH EXPERIENCED LEAR CREWS. 2) DISTRS: WX; TRIP RTE CHANGES; RADIO CALLS; AND TFC. 3) TIRED CREW.

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.