PPRuNe Forums - View Single Post - Cathay mulls 787-10 to replace A330s
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Old 18th Nov 2012, 10:24
  #18 (permalink)  
swh

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Originally Posted by cxorcist
Despite similar fuselage size, the 350-1000 will not carry anywhere near the payload HKG-JFK or LAX-HKG that the 777-300ER does. So it is not a 777-300ER replacement on missions over approximately 7000 air miles. Hence the reason CX is touting it for Europe. I think the only Pacific crossings you might see it on are YVR or SEA. The range numbers listed for the 1000 are very misleading because it won't carry the 40-50T payload that the 777 does over those distances.
Your data is out of date. The A350 now has a design rage of 8400 nm compared to 7900 nm for the 777-300ER, take around 15% off those numbers to get the range with the CX planning rules.

Originally Posted by cxorcist
Don't believe me, run the numbers yourself. For 350-1000:

MTOW ~ 302T
BOW ~ 160T (in theory)
Trip Fuel ~ 20% better than -300ER (in theory)
The A350 MTOW is 308 t, the relative trip cost is around 20% lower, fuel is around 25% lower (fuel is around 60% of the DOC). The A350 is around 20 million more expensive per airframe to buy.

Originally Posted by cxorcist
Looks like Airbus has come up short on wing and/or powerplant.
The 777-300ER and A350 have the same wing span, the A350 however has around 30 m^2 more wing area. The A350 wing is variable geometry, it changes shape during cruise to minimize drag. The L/D of the A350 is around 30-40% better than the 777-300ER.

The A350 thrust is 97 klb per side. The 777-9X which will have a wing with a similar L/D as the A350, however 36t higher MTOW, only has 99.5 klb of thrust from the GE9X engine per side.

Another comparison, the thrust to weight ratio of the A350 is better than the 787 and 777-9X, all have wings with L/D ratios in excess of 20:1.
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