WEST PALM BEACH, Fla. — Pratt & Whitney is pitching a souped up version of the F-35's engine that would add thrust and cut down fuel consumption, company officials disclosed on Wednesday.

The upgrade, which the company is calling the F135 Growth Option 1.0, could be cut into the existing production line by the early 2020s, said Matthew Bromberg, president of Pratt & Whitney military engines. Pratt manufactures the F135 for all three F-35 models as well as aircraft purchased by international customers.

"It's very attractive to the JSF [joint strike fighter] program for several reasons," Bromberg told journalists during a media day in West Palm Beach, Florida. "It's very common, so we could drop this upgrade into any one of the three variants. It would be compliant with the partner requirements and go to foreign partner countries. It would be cost neutral, so the upgraded JSF motor with Growth Option 1.0 would be the same price as the existing motor."

Pratt & Whitney recently completed performance tests of an early version of the system, called the fuel burn reduction demonstrator engine, which proved that the upgrade could improve thrust by up to 10 percent and reduce fuel consumption by up to 6 percent, he said. Reporters got to see the prototype in action during a May 30 demonstration at the company's test rigs.

Afterwards, Steve Burd, the company's chief engineer for advanced programs and technology, explained that the company funneled capabilities from two technology development programs — the Navy's fuel burn reduction effort and the Air Force's Component and Engine Structural Assessment Research (CAESAR) program —  into the Growth Option 1.0 configuration.

To upgrade the F135, only the power module would need to be swapped out for a new one with a more efficient compressor and improved turbine, including changes to the system's cooling, he said.

The new configuration is not funded through current joint strike fighter program of record, but if the F-35 joint program office approves it, the engine could be ready for the second round of upgrades under the Block 4 modernization effort, Bromberg said. The cost of the enhanced engine would be roughly the same as the current F135, but the Pentagon would have to pay for further development and validation of the technology.

"The technologies that we're developing on the rig you saw yesterday, those are some of the critical technologies that prove that we can actually execute the program," he said. "If we're given the green light to go, we would launch a relatively short engineering and manufacturing development program. We have to go through all of that validation. But we view that as low risk."

The Pentagon could opt to skip the growth option and wait for the results of the Adaptive Engine Transition Program, an ongoing Air Force effort to advance engine technology by adding a third stream of air, which helps optimize the propulsion system's fuel consumption and performance. Last year, the service awarded Pratt and General Electric Aviation a $1 billion contract each for further work on their engines.

Pratt's entry for AETP, the XA1010, has been hitting its developmental milestones on time, said Bromberg, noting the company might be able to move faster on the program if directed by the Air Force.