B737-700 first officer window cracked during flight.

Attributes
ACN	766023
Time
Date	200712
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : zoa.artcc
State Reference	CA
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	artcc : zoa.artcc
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	766023
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Supplementary
Problem Areas	Aircraft Chart Or Publication
Primary Problem	Aircraft

Narrative:

#4 first officer window cracked in-flight. Pulled out the QRH window damage checklist and idented it to be the outer pane. 'No restrs' except for window heat off and dialed up land altitude to 10000 ft and proceeded without further event. Later we discovered that the middle pane had cracked and not the outer as we suspected. It is very difficult to identify which window pane is cracked from viewing the windows from inside the cockpit. Suspect a previous bird strike on this window may have caused weakening and subsequent cracking.

Original NASA ASRS Text

Title: B737-700 FO WINDOW CRACKED DURING FLT.

Narrative: #4 FO WINDOW CRACKED INFLT. PULLED OUT THE QRH WINDOW DAMAGE CHKLIST AND IDENTED IT TO BE THE OUTER PANE. 'NO RESTRS' EXCEPT FOR WINDOW HEAT OFF AND DIALED UP LAND ALT TO 10000 FT AND PROCEEDED WITHOUT FURTHER EVENT. LATER WE DISCOVERED THAT THE MIDDLE PANE HAD CRACKED AND NOT THE OUTER AS WE SUSPECTED. IT IS VERY DIFFICULT TO IDENT WHICH WINDOW PANE IS CRACKED FROM VIEWING THE WINDOWS FROM INSIDE THE COCKPIT. SUSPECT A PREVIOUS BIRD STRIKE ON THIS WINDOW MAY HAVE CAUSED WEAKENING AND SUBSEQUENT CRACKING.

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.