Several companies the week of Feb. 27 revealed their offerings to replace the U.S. Air Force’s UH-1N Huey fleet, including Boeing [BA], Lockheed Martin [LMT], and possibly Textron [TXT].

The UH-1N Replacement Program plans to replace the Air Force’s entire Huey fleet with 84 new helicopters. They entered into service in the 1970s. The Air Force’ UH-1Ns currently protects the Minuteman II intercontinental ballistic missiles (ICBM) and launch sites and provides emergency transportation to support Continuity of Government Operations missions in Washington, D.C.

In February the Air Force said it would release a second draft request for proposal (RFP) in April following industry feedback that their current platforms do not meet all requirements contained in the initial draft. The final RFP is therefore expected to be released in the summer following the second draft. The Air Force plans to award a contract in FY ’18 resulting in the delivery of the first operational helicopter in the FY ‘20/21 timeframe.

Boeing revealed its MH-139 helicopter as its entry into the completion on March 2. The MH-139 is based on Leonardo Helicopter’s AW139 multi-mission helicopter. Boeing announced its competition bid at the Air Force Association Air Warfare Symposium held the week of Feb. 27 in Orlando, Fla.

According to a Boeing spokesman the company will be the prime contractor with Leonardo Helicopter as its subcontractor, producing the completed civil version of the aircraft at its Philadelphia, Pa. facility. Boeing will have total systems responsibility for this program and be the principle interface with customers to provide integration of military equipment not already on the civil aircraft.

The company will not develop a prototype or test the aircraft because it is based on the AW139. Boeing highlighted nearly 900 AW139s are currently in service around the world and one of its final assembly lines is in Philadelphia, Pa. “Just as the aircraft has met their individual requirements, Boeing will do the same for the USAF once their requirements are defined through a final RFP,” the spokesman added.

“The Huey replacement is of vital importance to the Air Force, and the MH-139 is the right solution for those missions. The fact that the AW139 is being built today on an active production line will speed it to meet the time-critical demand following the competition,” Judy Fedder, director of global sales & marketing at Boeing Integrated Logistics, said in a statement.

Sikorsky, a Lockheed Martin company, said on Feb. 28 it will offer the HH-60U Black Hawk in its bid to replace the Huey. The company noted the Air Force had previously assigned three UH-60M Black Hawks as HH-60Us when the aircraft was given modifications including an electro-optical sensor and a rescue hoist.

The company said this proposal would add up to 84 new in-production aircraft to the three HH-60Us already in the Air Force’s inventory. Air Force pilots and special mission aviators began flying the HH-60U in 2011.

Sikorsky highlighted the HH-60U shares 85 percent commonality with the Air Force’s incoming fleet of HH-60W Combat Rescue Helicopters and will share the existing infrastructure supporting the service’s retiring fleet of HH-60G Pave Hawks.

The company said the HH-60U offer has positive factors like a mature Black Hawk production line and established global supply chain; broad life-cycle cost savings from common dynamic parts, drive systems, and rotors; standardized fleet training devices, aircrew and maintainer courseware, and fleet logistics for logistical/readiness advantages; and identical digital cockpit avionics, a common pilot-vehicle interface, and other common training assets with the HH-60W fleet to facilitate transfer of maintainers and pilots between the two combat mission assets.

The HH-60U cabin can transport nine fully outfitted Security Forces specialists with critical security response equipment and two special mission aviators.

“Sikorsky’s HH-60U Black Hawk offers a proven, capable helicopter that is already in the Air Force’s inventory to meet the critical needs of the UH-1N Huey Replacement Program. It is a low-risk solution for the Air Force that will enable the service to support two vital national defense missions while realizing the long-term cost savings of the Black Hawk platform,” Samir Mehta, president of Sikorsky Defense Systems & Services, said in a statement.

A Bell Helicopter-Textron executive said the company was still mulling over whether to bid for the program but declined to provide further details. Possible offerings they have in production include the UH-1Y “Venom, AH-1Z “Viper,” and various commercial helicopters.

According to Bell Executive Vice President, Strategic Communications and Chief of Staff Bob Hastings, Bell is currently producing the Bell 407, 429, and 505 Jet Ranger X commercial helicopters. The Bell 525 Relentless helicopter is currently still in development, but the company is building flight test vehicles.

The final replacement contract could run in the $800-900 million range as a sole-source-like procurement.