Boeing MH-139 Grey Wolf. The Boeing MH-139A Grey Wolf is a twin-engine helicopter operated by the United States Air Force (USAF) for security and support missions. Developed by Boeing, the Grey Wolf is a variant of the Leonardo AW139, an Italian-built multi-role helicopter.

Development 
On 24 September 2018, the U.S. Air Force awarded Boeing a $2.4 billion contract to replace the aging UH-1N helicopter fleet, with the goal of enhancing security patrols of nuclear missile fields and transporting senior officials. This was the first major acquisition for the Air Force Global Strike Command in its 10-year history, following the cancellation of the previous Common Vertical Lift Support Program (CVLSP).  As part of this initiative, Boeing was awarded a $285-million contract to build the first 13 MH-139A Grey Wolf helicopters, to guard America's nuclear ballistic missiles.

The MH-139A Grey Wolf is to be used for security patrols, search and rescue missions, and personnel and cargo transport. The Air Force's first intention was to purchase 84 helicopters for security and transportation across extensive ICBM fields, and senior leader and executive airlift in the Air Defense Identification Zone (ADIZ), also known as the National Capital Region. It is also to be used in aircrew survival training. 

The precise quantity of the MH-139 fleet remains unknown. Initially, the requirement was for up to 84 helicopters, which was then reduced to 80, then 74. The most recent Fiscal Year 2025 budget suggests a further reduction, to a fleet of 36 MH-139s. The Grey Wolf program has faced numerous setbacks and delays, including difficulty with attaining Federal Aviation Administration type certification. Typically, FAA certification is not required for US military aircraft, but it is for the MH-139 because the helicopters are to be required to operate extensively within US domestic airspace.

Design 
The MH-139A Grey Wolf features military and commercial system integration capabilities that play a crucial role in the Grey Wolf program. It features an integrated training system based on existing AW139 operational flight trainers. Its sustainment tools ensure seamless USG interfaces. A global Commercial/DoD support system ensures efficient parts procurement. The unique design enables maintainers to conduct all aircraft maintenance at the operational level.

The helicopter is propelled by two FADEC-controlled Pratt & Whitney Canada PT6 turboshaft engines, housed in separate engine turbine burst containment boxes, each with independent inputs to the main gearbox. The engines' infrared signature has been decreased by lowering airflow and using a directed exhaust, reducing plume impingement upon the tail fuselage.

Operational history 

In March 2024, the first field-ready MH-139 Grey Wolf arrived at Montana’s Malmstrom Air Force Base. The 341st Missile Wing captured footage of Malmstrom's first Grey Wolf arriving at the base. The 908th Airlift Wing introduced the MH-139A Grey Wolf Helicopter at Maxwell Air Force Base on 31 May 2024. On September 1, 2023, the Pentagon issued a Selected Acquisition Report outlining plans to reintroduce 14 MH-139A Grey Wolf helicopters into the Air Force's program, bringing the total to at least 56 aircraft. This reverses a previous decision to cut the buy to 42 helicopters in the 2025 fiscal year, helping avoid a critical cost breach under Nunn-McCurdy.

Operators 

 United States Air Force
 413th Flight Test Squadron
 908th Airlift Wing
 341st Missile Wing

See also

References 

Military transport helicopters
2010s United States helicopters
Boeing aircraft
Twin-turbine helicopters