Narrative:

After pushback checklist complete and during push, I briefly unlocked/opened captain direct view window and closed again. During closing, although I did ratchet crank shut, I became distraction by interphone communications, and did not lock window lever. Continued with start, taxi and takeoff/climb. All normal. Requested block altitude FL410-FL430 -- approved and leveled off at FL420. I then noticed window unlocked. Tried to latch/secure but unable. Began normal descent and raised cabin/lowered differential, but still unable to secure. All pressurization still normal. However, decided to divert to jax to land and secure. Did not declare emergency. All indications normal. After refuel/new dispatch, continued flight. Even after an item is checked/verified on a checklist, if that item is subsequently changed, checklist should be re-run, or possibility of potentially critical items hit on before takeoff checklist. Although differential pressure would have probably kept window closed, I was concerned that I could not fully latch/secure the locking lever. At that point I thought as a precaution the best course of action was to land and secure.

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Original NASA ASRS Text

Title: CAPT OF AN LGT DIVERTED TO LAND AFTER FAILING TO PROPERLY LOCK SHUT HIS COCKPIT VIEWING WINDOW DURING HIGH ALT CRUISE FLT. NO EMER WAS DECLARED AND WINDOW WAS PROPERLY SHUT AFTER LNDG.

Narrative: AFTER PUSHBACK CHKLIST COMPLETE AND DURING PUSH, I BRIEFLY UNLOCKED/OPENED CAPT DIRECT VIEW WINDOW AND CLOSED AGAIN. DURING CLOSING, ALTHOUGH I DID RATCHET CRANK SHUT, I BECAME DISTR BY INTERPHONE COMS, AND DID NOT LOCK WINDOW LEVER. CONTINUED WITH START, TAXI AND TKOF/CLB. ALL NORMAL. REQUESTED BLOCK ALT FL410-FL430 -- APPROVED AND LEVELED OFF AT FL420. I THEN NOTICED WINDOW UNLOCKED. TRIED TO LATCH/SECURE BUT UNABLE. BEGAN NORMAL DSCNT AND RAISED CABIN/LOWERED DIFFERENTIAL, BUT STILL UNABLE TO SECURE. ALL PRESSURIZATION STILL NORMAL. HOWEVER, DECIDED TO DIVERT TO JAX TO LAND AND SECURE. DID NOT DECLARE EMER. ALL INDICATIONS NORMAL. AFTER REFUEL/NEW DISPATCH, CONTINUED FLT. EVEN AFTER AN ITEM IS CHKED/VERIFIED ON A CHKLIST, IF THAT ITEM IS SUBSEQUENTLY CHANGED, CHKLIST SHOULD BE RE-RUN, OR POSSIBILITY OF POTENTIALLY CRITICAL ITEMS HIT ON BEFORE TKOF CHKLIST. ALTHOUGH DIFFERENTIAL PRESSURE WOULD HAVE PROBABLY KEPT WINDOW CLOSED, I WAS CONCERNED THAT I COULD NOT FULLY LATCH/SECURE THE LOCKING LEVER. AT THAT POINT I THOUGHT AS A PRECAUTION THE BEST COURSE OF ACTION WAS TO LAND AND SECURE.

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.