Narrative:

During climb out we received an EICAS message; tire pressure. We confirmed on the gear synoptic page the number 6 main gear tire was slowly losing pressure. It continued to lose pressure during the flight and stopped at 20 psi. We completed all required checklists; and referenced all performance charts and limitations that were applicable to the condition. [Maintenance] was contacted to see if they could provide any history on other tire failures on the B777; and advise us on what to expect on landing and rollout. We were told the tire would most likely fail on the rollout. We planned our approach to this landing with that in mind. Dispatch was notified of the situation; and we requested they contact [destination ops] to plan for a possible 'aircraft unable to taxi' situation that would need stairs; buses; and a tug. I briefed the number 1 flight attendant on the situation; and the possible scenarios we might encounter on landing. We checked the weather along our route of flight; it was clear and forecast to remain VFR. I elected to increase our fuel burn above the flight plan figure to arrive with right+a fuel of 13;000 lbs; adding that to the 405;381 lbs gave us a landing weight of 418;400 lbs. At that landing weight with the current aircraft configuration; weight; weather; and performance penalties for 1 and possibly 2 brake failures provided a substantial safety margin. When center was contacted we declared an emergency providing them with the required information; and briefed them on the situation and requested emergency equipment meet the plane. We flew a normal approach and landing; and rolled out using only reverse thrust down to turnoff speed; and then only minimal braking to bring the plane to a stop. A visual inspection of the gear and tire showed it to be intact; we slowly taxied to the gate. The cabin crew did an outstanding job of preparing the passengers and cabin for what turned out to be a very normal landing. I cannot say enough good things about my first officer and relief pilot who made this scenario look easy with the way they handled it. This freed my time up to talk with the flight attendants; [maintenance]; dispatch; ATC and keep the big picture in view allowing me to analyze the situation and make changes as needed.

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Original NASA ASRS Text

Title: B777-200 Captain reported receiving EICAS message TIRE PRESSURE after takeoff; alerting the flight crew of low pressure in a main gear tire. They coordinated with all applicable parties and landed normally at destination.

Narrative: During climb out we received an EICAS message; TIRE PRESSURE. We confirmed on the GEAR SYNOPTIC page the number 6 main gear tire was slowly losing pressure. It continued to lose pressure during the flight and stopped at 20 PSI. We completed all required checklists; and referenced all performance charts and limitations that were applicable to the condition. [Maintenance] was contacted to see if they could provide any history on other tire failures on the B777; and advise us on what to expect on landing and rollout. We were told the tire would most likely fail on the rollout. We planned our approach to this landing with that in mind. Dispatch was notified of the situation; and we requested they contact [destination ops] to plan for a possible 'aircraft unable to taxi' situation that would need stairs; buses; and a tug. I briefed the number 1 Flight Attendant on the situation; and the possible scenarios we might encounter on landing. We checked the weather along our route of flight; it was clear and forecast to remain VFR. I elected to increase our fuel burn above the flight plan figure to arrive with R+A fuel of 13;000 lbs; adding that to the 405;381 lbs gave us a landing weight of 418;400 lbs. At that landing weight with the current aircraft configuration; weight; weather; and performance penalties for 1 and possibly 2 brake failures provided a substantial safety margin. When Center was contacted we declared an emergency providing them with the required information; and briefed them on the situation and requested emergency equipment meet the plane. We flew a normal approach and landing; and rolled out using only reverse thrust down to turnoff speed; and then only minimal braking to bring the plane to a stop. A visual inspection of the gear and tire showed it to be intact; we slowly taxied to the gate. The cabin crew did an outstanding job of preparing the passengers and cabin for what turned out to be a very normal landing. I cannot say enough good things about my First Officer and relief pilot who made this scenario look easy with the way they handled it. This freed my time up to talk with the flight attendants; [Maintenance]; Dispatch; ATC and keep the big picture in view allowing me to analyze the situation and make changes as needed.

Data retrieved from NASA's ASRS site as of July 2013 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.