Leonardo, the Italian-owned helicopter maker that employs 500 at its Northeast Philadelphia plant, and Boeing, which employs more than 4,000 at its Ridley Park helicopter factory, are rallying political and public support for Leonardo's made-in-Philadelphia MH-139 as the replacement for a fleet of as many as 84 aging U.S. Air Force UH-1N Huey helicopters, currently used to protect nuclear missiles and transport VIPs and service members.

The Huey has "served its country well" since the Vietnam War in the 1960s. But the Air Force says it's time for an update, said Jerry Drelling, a Boeing spokesman who came from Washington to Northeast Philadelphia airport Monday to watch a demonstration of the craft by Leonardo, formerly known as AgustaWestland.

Under the proposal, Boeing would administer the program, and Boeing engineers and technicians would oversee and perform systems integration by Leonardo workers at Leonardo's plant.

By using Leonardo's new aircraft design and its off-the-shelf parts, "we can save a billion dollars over the life cycle of this aircraft" compared with the cost of refitting and updating earlier-model rival helicopters, Drelling added. "We'll offer the lowest-cost aircraft.

The government put out a draft bid document earlier in April and hopes to receive formal bids this summer. The job is expected to cost at least $1.5 billion.

Lockheed Martin's Sikorsky Aircraft Corp. division will offer a version of its Black Hawk helicopter for the same job. The company "is actively pursuing the Air Force UH-1N helicopter replacement program. Sikorsky is offering the HH-60U, a proven, tested, and available aircraft to fully meet requirements for the Air Force's critical missile site and utility support missions," said Britt Rabinovici, defense systems and services communications manager for Sikorsky.

The company's main Black Hawk works are in Elmira, N.Y. The company also builds civilian helicopters at its plant near Coatesville.

Last year, area congressmen including Patrick Meehan (R., Pa.), who represents the Boeing plant neighborhood and has often advocated for Boeing projects, and Brendan Boyle (D., Phila.), who represents neighborhoods around the Leonardo factory; Bill Shuster (R., Pa.), chairman of the influential Committee on Transportation and Infrastructure; Bob Brady (D., Pa.); and Ryan Costello (R., Pa.), wrote to leaders of the House Armed Services committee urging it to require the Air Force "to conduct a fair and open competition" to replace the Hueys.

They said the Air Force had considered in 2010 "issuing a sole-source contract" for the job to a single manufacturer, and they expressed concern that the Air Force would attempt that again, which they called "a terrible precedent" that would "send the wrong message to U.S. industry."

Leonardo's "MH-139 is the right solution," retired Air Force Gen. Judy Fedder, now head of sales and marketing for Boeing Integrated Logistics, said in a statement last month.

The Leonardo helicopter is already in production (as the AW-139) and can be built and maintained for $1 billion less than the Black Hawk, according to David Koopersmith, vice president and general manager at Boeing's Vertical Lift division.

Leonardo says nearly 900 AW-139s are already in private, military, and government service around the world, including 250 built in Philadelphia.

Winning the contract would keep current Leonardo workers employed. It would not guarantee expansion.

Boeing last year laid off hundreds of workers in Ridley Park. The future of the plants' military contracts and assembly work depends on the pace of future Pentagon orders and the outcome of the many struggles over how the nation ought to plan and fight wars.