Farnborough Airshow

Lockheed, UTX chiefs 'hopeful' of F-35 debut

Time for F-35 to make it to Farnborough: CEO

American aerospace giant Lockheed Martin remains hopeful that its troubled F-35 fighter will make its debut at the Farnborough International Airshow in England, after a dangerous engine fire grounded its fleet in the U.S.

Event organizers confirmed Sunday that the F-35B Lightning II, one of the world's most advanced fighter jets, would remain in the U.S., after the Department of Defense refused to give it clearance. The military plans to inspect the engine built by Pratt & Whitney, a unit of United Technologies.

Read MoreF-35 Farnborough debut halted after engine fire

Marillyn Hewson, CEO of Lockheed Martin, told CNBC the company was looking forward to the "unique opportunity" to showcase the new product despite the setback. "We'll work through the issue, we'll get to the root cause," she said.

She said she's confident that defense officials were going through a disciplined process to find out the issues surrounding the fire so that they could be resolved—and the fighter jet could make the trip over the Atlantic to the annual Farnborough event.

"We're in a development program right now so we're in the midst of dealing with the particular issue, but it's like any aircraft development program: We work through the issue, we get to the root cause and we're hoping to see it here on the world stage later this week," she said.

Criticism of the F-35 is unfair: Rockwell Collins CEO

In a later interview on CNBC, United Technologies CEO Louis Chenevert echoed those sentiments. "I'm very comfortable working with the customer to [resolve] those issues and return the aircraft to flight shortly."

"The DoD is one of our largest customers. So we always work very closely with them," he continued. "The F-35, I'm still hoping it goes up at this show. I think there's still a chance.

Read MoreF-35 grounding threatens showcase at Farnborough

In June, Reuters reported that part of an engine on an Air Force F-35 A-model jet broke apart and ripped through the top of the plane as it prepared for takeoff at a Florida air base.

Responding to criticism of various setbacks, Hewson told CNBC the model is "well out of the gate" with regards to its development, and she was "extremely confident" that it would reach completion.

F-35 Lightning II
Source: Createordie | Flickr

Chenevert said: "The Pratt & Whitney core [in the F-35] comes from the F-22 fighter aircraft that has over a half a million hours. So I think it's a very mature core."

"And when you design," he added, "pushing the envelope with propulsion and the aircraft, sometimes you encounter things and you want to find those things out." He reiterated his confidence in a quick fix to the problem.

—By CNBC's Phil LeBeau and Matt Clinch