B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 346
Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution
Aircraft; Human Factors
First Officer's sliding window fully opened during takeoff at 85 KIAS. I took control of the aircraft at 90 KIAS and completed an uneventful takeoff while the First Officer attempted to close the window. After a few tries; he was unable and I elected to return to the departure field. All checklists and normal procedures were complied with during the visual approach return. Dispatch and the Chief Pilot on call were notified. We refueled; closed the window properly; and resumed the pairing. Two legs later; I was contacted by Maintenance Control after I had already performed a scheduled plane change.  I was told we should have written up the window and had it inspected. The FOM; under mandatory reporting; doesn't require Maintenance notification for this event since nothing had malfunctioned. I gave permission to use my employee number so they could do a write-up. I contacted my Chief Pilot and he agreed with me no write-up was required. Ensure that [new] first officer's close the window properly after it is opened.
B737 Captain reports the First Officer's sliding window coming open during takeoff; assumes control; and continues the takeoff. The First Officer is unable to close the window in flight and a return to the departure airport is required to close it.