Originally Posted by wxguy

All 777-300ERs are equipped with "Channel 9," a.k.a. "From the Flight Deck." SFO-MNL there will be very little to hear, except on the ground and take-off/landing. Over the ocean, communications are by CPDLC -- a digital transmission. If turned on during a transcon, there will be plenty to hear. But having it on is at the discretion of the Captain; the default is off. Some Captains put it on proactively; others refuse do to so. In the middle are a set who will turn it on if asked. I always ask (either by stopping by the cockpit before take-off or via an FA), and have about 50% success. YMMV!

The Wiki on this thread has a lot of good information.