NASHVILLE, Tennessee — Helicopter-makers say they’re eagerly awaiting a decision expected this summer from the U.S. Army to move forward with development of a futuristic rotorcraft.

The program, known officially as the Joint Multi-Role helicopter, or JMR, has attracted defense giants such as United Technologies Corp.’s Sikorsky unit, Textron Inc.’s Bell Helicopter, as well as the small, closely held firms AVX Aircraft Co. and Karem Aircraft Inc.

Despite automatic budget cuts, the service is trying to protect research and development funding to design next-generation helicopters that fly twice as far as today’s models and with better fuel efficiency, according to Heidi Shyu, the Army’s top acquisition official.

The Army is conducting a “significant amount” of analysis of vertical lift technology in preparation of “upcoming material development decisions,” she said during a presentation on Monday at the Army Aviation Association of America’s annual conference, known as Quad A.

“I would encourage all of you guys to go down and see the displays of all four competitors,” she said. “I mean, it’s really an outstanding job that each and every one of them are doing right now.”

The service may make a decision this summer to select two of the companies to continue developing designs, though no date has been set, according to Bell Chief Executive Officer John Garrison.

The firms will submit their proposals in June, the Army will make a decision in July, and the work will eventually lead to a potentially $100 billion Future Vertical Lift program to replace Black Hawks and Apaches, according to an article by Paul McLeary of Defense News.

Bell and Boeing developed the V-22 tilt-rotor aircraft, which can take off and land like a helicopter and fly like a plane. Now, they’ve split into separate teams, with Bell pitching a new, tilt-rotor concept called the Bell V-280 Valor and Boeing teaming with Sikorsky in offering a co-axial design called the SB>1 Defiant.

With its speed, range and payload capacity, “it provides operational agility and transformational reach that the armed forces, specifically the Army, do not have today,” Garrison said during a briefing with reporters. A prototype could fly as early as 2017, he said.

Bell’s life-sized model of the Valor attracted a steady crowd on the conference’s showroom floor. The aircraft is designed to cruise at speeds of at least 280 knots — hence its name — with a range of 2,100 nautical miles.

Unlike the Osprey, its engines remain in place and only the propellers tilt upward when transitioning, or rotating, from helicopter to airplane mode. The engineering change will drastically reduce wear and tear on the hydraulic lines and other components.

“It’s a simpler design,” Garrison said. “We have better and more modern tools today.”

The company also displayed a large touch screen running an interactive software program demonstrating the aircraft’s features, such as seats that wirelessly charge troops’ radios, night-vision goggles and other electronic gear; windows that display three-dimensional mission maps; and the upgraded wings and engines designed to stabilize flight while maximizing speed.

“It’s going to be a sports car — the way it’s going to fly,” said Keith Flail, Bell’s director of future vertical lift military programs.

Sikorsky also displayed a mock-up of another vertical-lift aircraft, the S-97 Raider, and miniature models of other experimental aircraft, including the Defiant, all of which are based on a coaxial design. Sikorsky made headlines on Monday not in Tennessee but in Florida, where it unveiled its new CH-53K chopper. The company expects to test fly the S-97 late this year.

Karem Aircraft Inc., founded by Abraham Karem, who designed the early MQ-1 Predator drone and A-160 Hummingbird unmanned helicopter, is developing a larger, “optimum speed” tilt-rotor capable of carrying an M2 Bradley or Stryker armored infantry vehicle.

Despite being the smallest player in the program, AVX, which is headed by engineers who worked on the V-22 program, was confident about its entry. Nicknamed War Horse by at least one company executive, the design features lighter rotors, a pair of rear pusher fans, minimal amounts of fasteners and other innovations.

“We don’t bring with us either a legacy or burden of overhead and other attributes that some of the big guys do,” said Scott Pomeroy, vice chairman of the company. “We also applaud the Army in recognizing that innovation is not the birthright of large multinational corporations.”

Troy Gaffey, chairman, president and chief engineer of AVX, said the Army may not decide to simply pick two of the four designs. It could pursue several options, including awarding funding for additional evaluations such as a wind-tunnel test that doesn’t require flight, he said.

“I suspect AVX will still be involved in one way or the other because of the technology that we’re bringing to the party,” he said. “We have a lot of technology in our aircraft that is, shall we say, new and different.”

(Story was updated to correct the name of the Sikorsky-Boeing design in the eighth paragraph.)