Presidential helicopter approaches key milestone.

• Author: Tadjdeh, Yasmin

After years of delays, the Navy and Marine Corps are on the cusp of replacing the service's aging fleet of presidential transport helicopters.

The services' effort, which has been more than a decade in the making, is now on track to meet key program milestones, officials said.

"The program is moving on or ahead of schedule," said Marine Corps Col. Robert Pridgen, program manager for Naval Air Systems Command's presidential helicopters program office.

For years, the Marine Corps has been attempting to replace aging presidential rotorcraft--known as Marine One--that have been in the inventory since the 1970s and 1980s. Former Secretary of Defense Robert Gates canceled a previous Lockheed Martin/AgustaWestland program--known as the VXX--after costs ballooned and requirements spiraled out of control, analysts said.

Even President Barack Obama famously criticized the program.

"The helicopter I have now seems perfectly adequate to me," he said in 2009. He called the program "an example of the procurement process gone amok. And we're going to have to fix it."

After recompeting the program, Sikorsky's S-92 aircraft was chosen in 2014 for what is now known as the VH-92A. The Marine Corps is equipping the system with proven, mature technologies, Pridgen said.

When "we went into the 92, we were looking for stable requirements--things that we understood. This was not going to be an S&T" project, he said. "We're developing more mature capabilities."

Under the contract, Sikorsky--which Lockheed Martin recently acquired from United Technologies Corp.--will provide the Marine Corps with 23 helicopters. Initial operating capability is slated for 2020. Production will end in fiscal year 2023.

The next milestone for the program is the VH-92A's subsystem critical design review at the end of July, he said. "[Our] engineers come up and they show that they understand not only the design, but that the design meets the requirement and that requirement is in keeping with the specs that we had laid out," he said.

The review is occurring earlier than originally scheduled, he noted.

From there, "you start cutting metal," Pridgen said during a briefing with reporters in May. "You start solidifying the final drawings and we start moving out and modifying the aircraft."

By spring 2017, the Marine Corps will have either flown or will be preparing to fly its first engineering and manufacturing development helicopter, he said.

"If you look at the schedule that's a pretty...