B777 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 210; Flight Crew Total 15000; Flight Crew Type 1000
Situational Awareness
Deviation - Speed All Types; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Flight Crew Became Reoriented; Flight Crew Took Evasive Action
Aircraft; Human Factors
Invalid dispatch with MEL 3232D with a weight of 620;000#. MEL called for a max of 270 kts/M.82. FPF planned for M.82 but not 270 kts. Approaching cruise altitude of 8900 meters or FL291 and deviating around thunderstorms; we were unable to maintain 270 kts in turbulence and keep 15 kts above stall buffet.
Flt from ZBAA had a Mel 3232D which restricted the aircraft to 270/.82 for a gear door spring. The Flt was planned at 8900 meters which is 29100 feet. It was planned at .82; at that altitude the aircraft was above the 270 kts Mel restriction. The flying crew left the seat at approximately 25000 feet and climbing. We were talking to Beijing and looking at two cells at our 12 and 2 o'clock both above 30;000 feet. As I replaced the Captain who was the PF I noticed we were at 270 Kts and the stall bar was at 265 and closing in on 270. I told the captain before he left I was going to accelerate to maintain a margin above the stall bar. Not long after that we encountered Mod turbulence; we sat the flight attendants and asked for a climb even though this would force us to maintain a speed higher than the MEL required. We were VMC navigating between two cells with significant clearance but in turbulent air. Every FIR we came to we had to inform them we would be flying at a significantly lower airspeed then planned due to an operational restriction. Then when we queried dispatch and he discussed the Mel with the SABRE manager he indicated he was aware of the MEL restriction yet we still had a Flt plan that didn't comply with it. The initial altitude and airspeed with our weight were not even close in being in compliance with the Mel.
B777 flight crew reports being dispatched with an MEL restricting airspeed to 270 KIAS or Mach .82. At FL291 270 knots is close to clean maneuver speed and deemed too low for flight in turbulent air.