Takeoff distance for an A333, MTOW (235t), at sea level, in ISA conditions, with RR engines, is roughly 11,000 feet.
Takeoff distance for an A343, MTOW (276.5 t), at sea level, in ISA conditons, with highest rated engines (CFM56-5C4) is roughly 10,200 feet.
Now here is what is puzzling. How come the A343, with 40 more tonnes of payload, has better takeoff performance than the A333, considering the fuselage and wing area are identical, and so is the engine thrust total for both aircraft (If anything, the A333 (142,000 lbf) has a few thousand more lbf of thrust compared to the A343 (136,000 lbf total).
The only answer i can see based on the sources i provided is the flap setting on takeoff. For the A343, we can see on the charts that Flaps 3 must be selected for sea level takeoffs. There is no flap indication whatsoever on the charts for the A333. Does that imply that a no flaps takeoff is the norm for the A333?
If not, what is a typical flap setting for the A333? I read on another post that flaps 1, 1+F, or 2 are standard. Does the A333 ever need flap 3 for takeoff?
Thanks in advance.
[Edited 2013-02-19 07:08:03]