The U.S. Navy program to find a replacement for the “Marine One” Presidential helicopter is looking set to become a one-horse race following the withdrawal of AgustaWestland and Northrop Grumman.

The two companies had partnered to offer the AW101 three-engined helicopter for the VXX requirement to replace the aging fleet of Sikorsky VH-60 Whitehawks and VH-3 Sea Kings, but have decided to withdraw after analyzing the request for proposal documents.

In statement to Aviation Week, an AgustaWestland spokesman said: “After a comprehensive analysis of the final RFP, dated May 3, 2013, we determined that we were unable to compete effectively given the current requirements and the evaluation methodology defined in the RFP.

“There are fundamental proposal evaluation issues that we believe inhibit our ability to submit a competitive offering, and that provide a significant advantage to our likely competitor.

“The decision to withdraw was most difficult, as we believe we have the best, most suitable aircraft for the President.”

Boeing too has also decided not to participate in the program with either the V-22 Osprey it jointly produced with Bell or the CH-47 Chinook. A spokesman for the company said: “The Boeing Company will not submit a bid for the U.S. Navy’s VXX Presidential Helicopter program.

“While both the Boeing H-47 Chinook and the Bell Boeing V-22 are often used to transport military and government leaders in theaters of operation, we do not believe these aircraft would be competitive for this program as it is currently structured.”

The spokesman said that the team remains focused on delivering V-22 Ospreys to Marine Helicopter Squadron One (HMX-1) for what it calls the “greenside presidential support role.”

The withdrawal of the two teams leaves Sikorsky and system integration partner Lockheed Martin as the sole bidding team, offering Sikorsky’s H-92 platform based on the S-92 civil helicopter. The two companies also ended up being the sole bidders in the U.S. Air Force’s 112-aircraft, $6.85 billion Combat Rescue Helicopter (CRH) program to replace the Air Force’s aging fleet of HH-60G Pave Hawk CSAR helicopters. Other bidders AgustaWestland and Northrop Grumman, Boeing and EADS North America all pulled out in December 2012 because they said the source-selection rules for the restaged competition “provided little or no credit for exceeding the requirements.”

A spokesman for Sikorsky said: “We have prepared our proposal anticipating a full and open competition against other industry teams. We firmly believe we have the ideal team to deliver the best aircraft, on time and within budget.”

The AW101 was selected for the VXX requirement during the first VXX competition back in 2005, but the program was canceled when costs rose significantly. The nine VH-71 airframes were later transferred to Canada for use as spare parts for the country’s CH-149 Cormorant search and rescue helicopter fleet.