Boeing 737 MAX airplanes sit parked at a Boeing facility adjacent to King County International Airport, known as Boeing Field, on May 31, 2019 in Seattle, Washington. Boeing 737 MAX airplanes have been grounded following two fatal crashes in which 346 passengers and crew were killed in October 2018 and March 2019.
David Ryder | Getty Images News | Getty Images
U.S. aviation regulators won't likely clear Boeing's troubled 737 Max airplanes for flight until 2020, Federal Aviation Administration chief Steve Dickson told CNBC on Wednesday.
Dickson's comments squash any hope that Boeing had of getting the planes re-certified before the end of the year.
"Like I said there are a number of processes, milestones, that have to be completed," Dickson said in an interview on "Squawk Box." "If you just do the math, it's going to extend into 2020."
The return date of the fuel-efficient planes has repeatedly slipped. The uncertainty has been a challenge for airlines like Southwest and American, which have lost hundreds of millions of dollars in revenue with the planes out of service. U.S. airlines that fly the planes don't expect them back in service until at least early March.
Even if the FAA approves the planes, airlines will have to take mothballed planes that have been grounded since March and train thousands of Boeing 737 pilots.
Dickson said there is no clear timeline for when the 737 Max will be re-certified and that there are 10 to 11 milestones left to complete before it can be approved.
"We're going to follow every step of the process, however long that takes," he said. "I've made it clear that I'm going to support my people and that means they are going to take whatever time it takes to get this process completed and to do it the right way."
Dickson added that his team is currently in the process of reviewing the plane's software and "the validation of how the software was developed."
Boeing CEO Dennis Muilenburg has not made "any requests to cut corners" throughout the re-certification process, Dickson said. There have been "discussions from time to time about which processes run in parallel, where the interdependencies are," Dickson said. He added that this dialogue is not counterproductive.
The FAA has been under fire for its approval of the now-grounded 737 Max and Dickson said at an industry conference in early November that the agency will work to better assess how human pilots interact with increasingly automated and complex aircraft. He also said that human factors should be considered "throughout the design process."
Dickson was sworn into a five-year term as FAA administrator in August.
This is a developing story please check back in for updates.