The MH-139 is based on the Leonardo AW139 and is modified with mission-specific equipment, systems, and armament by prime contractor Boeing.
Features include an open-architecture glass cockpit, weather radar, enhanced ground proximity warning, radar altimeter, engine IR signature reduction, and military UHF/SATCOMS.
The helicopter also features defensive systems such as chaff/flares and missile warning, cockpit and cabin ballistic protection, and crashworthy, self-sealing fuel tanks. AFGSC aircraft will be optionally armed with cabin-mounted 7.62 mm M240 machine guns.
USAF awarded Boeing the $2.4 billion UH-1N replacement contract on Sept. 24, 2018, following cancellation of the earlier Common Vertical Lift Support Program (CVLSP). Requirements were driven by the MH-139’s primary ICBM-field security and support role, but targeted to eventually replace UH-1Ns in the DV lift and aircrew survival training roles as well.
Since the commercial AW139 is a mature system, USAF streamlined developmental testing to focus on mission requirements. IOC was initially pegged for 2021 but developmental flight-testing uncovered performance limiting deficiencies in crosswinds, degraded visual conditions, and austere operating conditions that delayed FAA and subsequent military certification to August 2022. Six helicopters conducted USAF-led developmental testing expanding the flight envelope, validating mission suitability, and developing tactics prior to starting operational testing on Jan. 28, 2025.
Development is focused on fixing intercom, machine-gun ammunition feed system, mission planning, and cabin layout problems. USAF is also working to solve engine debris ingestion issues that have restricted operations from unimproved surfaces, evaluate heavyweight, hot/high-density altitude performance, and validate the effectiveness of the IR self-defense systems.
USAF approved low-rate initial production in March 2023, and FY25 request included funds for eight aircraft with a total of 13 slated for delivery this FY. The first production aircraft was delivered to Malmstrom on Aug. 5, 2024, and a decision to ramp up to full-rate production of 15 helicopters annually is expected this year. The service reduced its 84-helicopter buy to 42 due to budget constraints in FY24 before raising the number to 56 to avoid triggering a Pentagon program review.
AFGSC’s three missile bases and the schoolhouse at Maxwell are unaffected by the change, though Andrews, Fairchild, Kirtland, Duke Field, and Yokota will continue to operate the UH-1N. Malmstrom took delivery of the first operational MH-139 on March 9, 2024, while Maxwell received its first MH-139 on April 3, 2024.
MH-139 Grey Wolf Technical Data
Contractors: Boeing (prime contractor); Leonardo (formerly AgustaWestland) (airframe); Honeywell (avionics).
First Flight: 2019.
Delivered: Dec. 19, 2019-present
IOC: 2023 (planned).
Production: 84 (planned).
Inventory: Eight.
Operator: AFMC. Planned: AETC, Air Force District of Washington, AFGSC, PACAF.
Aircraft Location: Duke Field, Fla. Planned: Fairchild AFB, Wash.; F. E. Airman 1st Class Davis Donaldson Samuel King Jr./USAF Warren AFB, Wyo.; JB Andrews, Md.; Kirtland AFB, N.M.; Malmstrom AFB, Mont.; Maxwell AFB, Ala.; Minot AFB, N.D.; Yokota AB, Japan.
Active Variant: •MH-139A. Military version of the Agusta-Westland AW139 for utility support and light lift.
Dimensions: Rotor diameter 45.2 ft, length 54.7 ft, height 16.3 ft.
Weight: Max gross 14,110 lb.
Power Plant: Two Pratt & Whitney PT6C-67C turboshaft, each 1,100 shp.
Performance: Speed 167 mph, range 890 miles.
Ceiling: 20,000 ft.
Armament: Two M240 7.62 mm machine guns (mission dependent).
Accommodation: Two pilots, flight engineer.
Load: 15 passengers (depending on fuel, equipment, and atmospheric conditions) or up to four litters and five medical personnel.
