Bombardier is waiting until the first three CSeries test aircraft are flying before announcing a new service-entry date for the all-new narrowbody airliner, say company executives.

The second aircraft, FTV2, is expected to join FTV1 in the flight-test program “in a couple of weeks,” and FTV3 “will follow right after,” says Bombardier Aerospace President Guy Hachey in an interview with Aviation Week at the Aero Montreal forum.

“What we’re doing is taking our time to assess how FTV1 and FTV2 are going to be doing and at what rates we can get the [flight-test] hours done,” he says.

“So far we’re pushing the organization to do a one-year flight-test program. It’s very aggressive, and we understand that, but we’re not leaving that until we’ve had a full evaluation of how we’re doing,” Hachey says.

The initial CS100 variant of the CSeries was planned to enter service in mid-2014, and the larger CS300 a year later, but when first flight slipped past the end of July, as scheduled, Bombardier stopped giving in-service dates. FTV1 eventually made its first flight on Sept. 16, and analysts predict service entry for the CS100 will slide into early 2015.

“We will get FTV3 in the air, get early data, then solidify the schedule,” says Rob Dewar, Bombardier vice president and general manager for the CSeries. “So far there are no major problems.”

FTV3 is the avionics-test aircraft and is planned to fly from Mirabel to Bombardier’s flight-test center in Wichita for testing. As the Canadian winter sets in, other aircraft may also fly south if the weather in Wichita looks better for testing, Dewar says.

The CSeries has had what looks like a slow start to testing, with the flights interspersed with extended periods of ground testing and aircraft upgrades. Bombardier says this is a deliberate plan to ensure as many flights as possible qualify for certification credit.

“In the past we liked to fly. It takes a lot of discipline to make sure the aircraft is in the right configuration so that when we fly, we get certification,” says Dewar, adding, “We measure test points, not flights.

“We do more testing on the ground, so flight is a validation,” he says. “We planned an extensive flight-test program, but we may be able to reduce that.” The original plan is for 2,400 hr. of flight tests with five CS100s.

“We do not fly just to fly. There has to be earned value from flying, to get the check marks [against certification tasks],” says Hachey. “And from the perspective of earned value I am happy with our progress.”

Bombardier is in discussions with risk-sharing partners and suppliers as it reevaluates the CSeries, he says, to understand the maturity of their systems and components.

There will be an impact on program costs from any further delay in service entry, but Hachey says non-recurring cost for CSeries development is still $3.4 billion ($3.9 million including interest expense).

But some of the extra costs are being allocated to other accounting “buckets” within the program. “There has been a move between recurring expenses—what goes on the aircraft itself—versus non-recurring,” he says.

“So yes, there’s been movement among the buckets. But when I look the total business case [for the CSeries] and what we anticipate to sell in the marketplace over the life of the program, we’re still well within what we anticipated—the return on investment we’re looking for,” Hachey says.

“What’s important is that for us the business case still makes sense. We are very close to entry into service—we’re a year or so away in terms of the flight-testing program—and we still feel very comfortable with the business case,” he adds.