Boeing reaffirms it is on track to develop the 777X derivative for service entry by the end of the decade and is not stalling the new widebody project.

Denying a Seattle Times report that development progress is slowing, Ray Conner, president and CEO of Boeing Commercial Airplanes, says, “Our timing on a decision to offer that airplane has not changed. We are absolutely committed to the 777X and continue to invest the necessary time and resources to ensure we produce a superior airplane for our customers.”

In an internal message to employees, Conner also says that 787-10X development continues on schedule. “As with the 777X, we want to make sure that we respond to our customers’ business needs and that we develop a plan that is well-defined and leads to success.”

According to the newspaper report, the slowdown is tied to possible concerns over the timing and level of investment needed for the new developments. The timing of both programs will come as Boeing launches into the peak of spending for other commitments such as the 737 MAX narrowbody.

The article also says the apparent slowdown is upsetting potential customers such as Emirates, which already has stated its desire for the 777X as soon as Boeing can deliver. However the airline warns that it cannot wait for the 777X if Boeing opts to slide entry-into-service (EIS) toward a suggested date beyond 2020.

The 777X is under study for EIS around 2019 and widely expected to feature an all-new composite wing as well as new-generation engines. The development could include two family members, and is aimed at opening up a new market sector above the 777-300ER, as well as countering the A350-1000, the largest member of Airbus’ new twinjet family. With a potentially larger wingspan that the 777-300ER, the 777X is expected to become a pivotal part of Boeing’s new product family lineup in the 2020s and beyond.

The 323-seat 787-10X will be stretched around 18 ft. and is aimed at replacing aircraft such as the A330-300, albeit with a 25% lower block fuel burn. The -10X also is designed to compete with the A350.

Although Boeing will not discuss details of the program schedule, the firm configuration of the 787-10X is expected to be fixed around mid-2014. Detailed design is expected to be completed by late 2016 with EIS as early as 2018, though more likely in 2019. The 777X effort is widely expected to follow a similar schedule.

Conner says, “Teams are working the many variables of a complex, integrated product development process, and we continue to work with a number of customers on their unique requirements. To that end, we’ve held formal and informal meetings with customers designed to facilitate a two-way conversation about our plans for these products.”

Describing these talks as “robust conversations,” he adds “when we are satisfied with the risks, costs and schedule, as well as many other important factors, we intend to present a plan for offering these widebody airplanes to customers. The airplanes would enter the market late this decade. My position is that when we are ready, we will go.”