HS125 first officer reports pressurization loss at FL188 during climb and ensuing descent.

Attributes
ACN	835607
Time
Date	200905
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	HS 125 Series 600
Operating Under FAR Part	Part 135
Flight Phase	Climb
Route In Use	SID ZZZZZ
Flight Plan	IFR
Component
Aircraft Component	Pressurization System
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 82 Flight Crew Total 8260 Flight Crew Type 285
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

While climbing out we lost pressurization and had to execute a descent. Maintenance is troubleshooting the problem. ATC was very helpful!

Original NASA ASRS Text

Title: HS125 First Officer reports pressurization loss at FL188 during climb and ensuing descent.

Narrative: While climbing out we lost pressurization and had to execute a descent. Maintenance is troubleshooting the problem. ATC was very helpful!

Data retrieved from NASA's ASRS site as of April 2012 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.