The Navy issued a final request for proposals for the next presidential helicopter that will replace the aging fleet of Marine Corps aircraft.

The competition among industry is expected to involve several major defense firms in the bid to provide up to 23 of the new helicopters under the VXX program. The deadline for submitting proposals is Aug. 1.

The VXX program is designed to replace the VH-3 Sea Kings and smaller VH-60 Whitehawks that have been used by the Marine Corps to ferry presidents for decades under the call name “Marine One.” Both are built by Sikorsky, a division of United Technologies [UTX].

Several companies are expected to be in the running for the contract. Sikorsky will offer its baseline S-92 airframe along with partner and systems integrator Lockheed Martin [LMT].

“The men and women of Sikorsky and Lockheed Martin are ready to offer Sikorsky’s proven S-92 helicopter in response to the U.S. Navy’s formal request for proposals to build the next Marine One helicopter fleet,” Sikorsky said in a statement. “Sikorsky brings unmatched experience having flown every commander in chief since President (Dwight) Eisenhower.”

Northrop Grumman [NOC] and AgustaWestland, a unit of Finmeccanica, announced a partnership in September that will be based on AgustaWestland’s AW 101 airframe.

Boeing [BA] is expected to compete with either its H-47 Chinook airframe or the V-22 Osprey it currently builds with partner Bell Helicopter, a Textron [TXT] company. Boeing spokesman Damien Mills said the company will review the requirements outlined in the RFP before determining which platform is most suitable.

Boeing and Bell are already supplying the tilt-rotor V-22s to carry equipment and White House staff as part of the presidential entourage. The first of the planned 12 MV-22s arrived with the squadron at Marine Corps Base Quantico, Va., in early April.

Flight operations began April 26, but flights carrying presidential support staff and news media in the Ospreys won’t begin until later this year, said Capt. Richard Ulsh, a Marine Corps spokesman.

A previous Marine One replacement program was canceled in 2009 by then-Defense Secretary Robert Gates after it fell under heavy criticism for anticipated cost overruns and delays, ending a process that had begun six years earlier.