Airbus is to offer carriers a higher-weight A330-300 from the fourth quarter of this year, taking the maximum take-off weight (MTOW) to 235t.
Raising the MTOW would extend the range by 135nm (250km) with a typical 300-passenger load, or provide a 1.4t payload increase at a range above 4,200nm. TUI Group is ordering a pair of the jets, with 362 seats, for its French division Corsair.
Airbus has identified the new weight variant as WV54. It will offer a 2t increase in MTOW over its predecessor, the WV52, and 5t above the baseline WV50. The airframer says that design-load analysis indicates that the 2t increase is achievable if it is "compensated" by a 2t reduction in maximum zero-fuel weight, to 173t.
Maximum landing weight, 187t, will remain unchanged from the WV52. Local structural modifications will be required for the new airframe - including changes of rivets in the forward lower fuselage shell - but these will have "negligible impact" on aircraft empty weight. Part of the change has already been implemented as part of A330-200 production.
Airbus says it wants to increase the payload-range performance of the A330-300 while "taking full benefit of demonstrated wing structural capability".
Maximum aft position of the centre-of-gravity has been reduced at the higher weight, to keep vertical static load on the main landing-gear unchanged.
"These improvements have been achieved with little impact on the aircraft's operability, meaning that the aircraft will be able to use most of the existing runways and the airport take-off slots without penalty," says Airbus.
Take-off and go-around thrust are unchanged on the higher-weight variant, which will require a 70-90m (230-300ft) increase in take-off distance.
But while the Rolls-Royce Trent 772- and Pratt & Whitney PW4170-powered versions of the aircraft will meet QC2 take-off noise criteria, slight engine modification will be needed for certain airframes equipped with General Electric CF6-80E1s.
The A4 model of the GE powerplant will fall within the QC2 threshold, says Airbus, but not the A3 model.
In order to bring the latter into line, GE is developing a nacelle modification and noise tests are scheduled to take place in the first quarter of this year, with certification planned for the third quarter.
Although the engine modification will be available through retrofit, Airbus is not offering the higher-weight airframe as a retrofit package. But it says this possibility "will be investigated...depending on customer requests".
Airbus expects delivery slots for the new A330-300 variant to become available from the first quarter of 2012. Its A330-300 backlog at the end of 2010 stood at 141 aircraft.