Airbus is sticking to its schedule of starting A350 XWB final assembly at the end of this year, with entry into service in the second half of 2013.
Parent company EADS confirmed the timetable as it disclosed the airframer's first-quarter performance. But it says the "programme remains challenging".
EADS chief Louis Gallois said: "While advancing with the A350 XWB through achieving several critical milestones, this decisive programme continues to require our closest attention."
Airbus's earnings from its commercial operation increased to €125 million over the first three months, as revenues rose 12% to €6.7 billion ($9.6 billion).
It delivered 119 commercial aircraft, against 122 in the previous first quarter when it turned in earnings of just €6 million.
The company benefited from "favourable mix effects and a pricing improvement net of escalation".
But it adds that the year-on-year improvement was partly reduced by higher research and development expenses, particularly on the A350, as well as hedge-rate deterioration of €110 million.
Airbus secured orders for 69 aircraft in the first quarter including 10 A380s, while it gained extensive commitments to its new A320neo family.
EADS is expecting a "significant improvement" in its group earnings during 2012 as a result of higher volume, better pricing and an improvement of A380 performance.