When Textron Aviation unveiled the prototype of its flagship Cessna Citation Longitude jet in 2015, the Wichita-based company expected to begin deliveries just two years later.
But before it could deliver the jet, it needed to get Federal Aviation Administration type certification.
And that's been a moving target.
The Longitude was originally expected to enter service in 2017. That date moved to early 2018 when Textron Inc. CEO Scott Donnelly told analysts last October there was an "obsolescence issue" with one of the jet's key suppliers. He said that delayed the plane by "a couple of months."
Now there are fewer than seven months left in 2018.
The certification process has changed a lot since the last time the company certified a wholly new design, the Citation Sovereign.
"We've had to step up to like, 10 years of rules changes," said Brad Thress, Textron Aviation's senior vice president of engineering.
FAA spokeswoman Elizabeth Isham Cory said in an email to The Eagle that since the Cessna Citation Sovereign's type certification as a wholly new design, "the FAA has updated many transport airplane standards . . . based largely on in-service incidents and accidents or potential precursors to accidents."
"Meeting the latest standards ensures that new airplanes contribute to the continued safety of the U.S. and worldwide fleet of airplanes," she said. "Those safety requirements may add additional testing, but that is typical of any new type certification project.
Textron Aviation has used five aircraft and nearly 50 ground test articles for the Longitude's certification. Before, it typically used three aircraft and fewer than 30 ground test articles for certification.
"This is the most robust certification process we've ever been required to conduct for a Citation," Thress said.
It's something that's not unique to Textron Aviation.
Gulfstream, the Georgia-based large business jet manufacturer, has also had to move the entry-into-service date for its G500 from 2017 to sometime in 2018. Gulfstream officials didn't respond to a request for comment.
The Longitude is an important airplane for Textron Aviation.
It is expected to stimulate new business and revenue for the company that employs 9,000 people in Wichita.
The jet also is Textron's largest and longest-range Citation with a $26.9 million price tag, which likely gives the company a wider profit margin among its 13 piston, turboprop and jet aircraft models .
It’s a very strategic airplane for us," Thress said. "It puts us in a new market ... and it gives our (existing Citation) customers a way to move up and stay in the family."
The Longitude is also bringing in customers who have never before owned a Citation, Thress added.
It does appear that Textron Aviation is moving closer to type certification.
In the next day or so, it will wrap up its own flight testing, which amounts to 3,000 hours of flying time. And the company is prepping its fourth Longitude test aircraft for the last flight activity in the FAA's certification process, which is function and reliability testing.
Along with the F&R testing, the company is preparing more than 200,000 pages of documents it will submit to the FAA for type certification, Thress said.
He said the company has orders for Longitudes and has already been producing them. That's standard for the company, even if something turns up during the certification process and Textron Aviation has to go back and change the aircraft it has already produced.
"That’s normal ops for us," Thress said. "We think it allows us to get to the market sooner and it’s a strategic advantage for us."
The company wouldn't disclose how many production Longitudes have been completed thus far.
But "customers are anxious for their airplanes," Thress said.
How soon they'll get them this year isn't clear.
Normally, the function and reliability testing requires about 300 more hours of flying, said business aviation forecaster Rolland Vincent, who said that could be "two-plus months."
Thress said the FAA may not require that many hours on the Longitude since there are already 3,000 hours from the company's flight testing. "But that's yet to be determined," he said.
"I don’t think F&R will drive (type certification)," Thress said. "I think documents will drive the date."