WASHINGTON — Lockheed Martin Sikorsky and Sierra Nevada Corp. have opted not to protest the U.S. Air Force’s recent decision to award a contract for the UH-1N program to Boeing, a decision that safeguards Boeing’s victory over what was seen as its major rival.

Last month, a Boeing-Leonardo team beat out Lockheed and Sierra Nevada Corp. to win the $2.38 billion contract for its MH-139 helicopter in a major upset. Boeing’s bid was considered a long shot by defense analysts, as the Air Force had initially considered sole-sourcing Lockheed’s UH-60 Black Hawk and SNC put forward a recapitalized version of used Army UH-60s.

As such, a protest by Lockheed was heavily anticipated, especially as the company previously filed an unsucccessful bid protest over the Huey replacement program’s data rights requirements. However, the company has decided to not pursue it.

“After a thorough review of the debriefing materials, Sikorsky has chosen not to protest the U.S. Air Force’s decision on the UH-1N Huey replacement program,” Lockheed said in an Oct. 9 statement.

“Sikorsky remains confident that its HH-60U Black Hawk offering is the strongest, most capable solution for the critical no-fail mission of protecting our nation’s nuclear missile silos and supporting the continuity-of-government mission. We look forward to working with the Air Force on future procurements and remain committed to delivering superior helicopters on our existing and future contracts.”

SNC also acknowledged on Tuesday that it would not protest the award.

“While we are disappointed by the recent UH-1N announcement, Sierra Nevada Corporation will not protest the decision," the company said in a statement. "We are confident that our innovative Sierra Force helicopter provides an affordable and high-performance solution and we remain committed to offering this advanced, disruptive technology in both domestic and international rotary-wing markets.”

The Huey replacement contract’s final contract value — about $1.7 billion less than the Air Force’s $4.1 billion projected value — hints that Boeing had bid aggressively low on a fixed-price award under which the company assumes the risk for cost overruns. That may be one reason why Lockheed and SNC decided to forgo a bid protest this time.

Boeing has won three hotly anticipated aircraft contracts in the past few weeks: the Huey replacement, the Navy’s MQ-25 tanker drone and the Air Force’s T-X trainer jet. Two of those awards, the MQ-25 and Huey, seem to have been accepted without the losing contractors disputing the award through the Government Accountability Office — a sharp contrast to the status quo of several years prior, where bid protests were the expected response to every lost competition.

Acquisition officials complained then that the ensuing legal fights wasted time and money, with Congress going as far as to propose financial penalties for companies that launched undue protests. Lawmakers eventually decided against that idea.

The Air Force plans to buy 84 new helicopters over the course of the program, with the first aircraft being delivered in fiscal 2021.

Updated on Oct. 9, 2018 at 3:18 p.m. with SNC’s statement.