The integration of two defensive systems on the Boeing [BA] MH-139A helicopter has delayed two Federal Aviation Administration (FAA) supplemental type certificates (STC) for the aircraft–both required approvals, given that the helicopter adds military equipment to the Leonardo-supplied AW139 commercial helicopter.

The MH-139 defensive systems are the BAE Systems ALE-47 Airborne Countermeasures Dispenser System and the Northrop Grumman [NOC] AAR-47 Missile Warning System. Florida-based Extant Aerospace said that it has been the Air Force’s prime contractor for the ALE-47 since 2001. Extant Aerospace said that it buys OEM designs for older products, or licenses them from the builders, in order to allow OEMs to focus on new product development.

In fiscal 2021, the Air Force received $194 million for eight MH-139As, but the service has budgeted none for fiscal 2022 because of the FAA STC approval delays.

“This aircraft needs three supplemental type certs,” Air Force Lt. Gen. Duke Richardson, the service’s top uniformed acquisition official, told a June 22 Senate Armed Services Committee Airland panel hearing on the Air Force’s fiscal 2022 budget request. “Supplemental Type Cert number three has already been granted. One and two are behind. The one we’re most worried about is the second one, and it has to do with a defensive system that has a nacelle around it. It’s causing some funny air disturbances, and we’re working to understand those air disturbances so that we can get the Supplemental Type Cert for that.”

“It’s not necessarily that the FAA is being slow or anything like that,” Richardson said in response to a question on the program from panel chairwoman, Sen. Tammy Duckworth (D-Ill.). “It’s really just trying to work through those technical issues. When we look at the program, it’s not ready for production.” Richardson said that the service plans to fund MH-139 production in fiscal 2023 once it validates technical fixes.

The Air Force, in response to an email question, wrote on June 23 that the ALE-47 and AAR-47 subsystems “are not causing the problem.”

“The integration of them on the aircraft, specifically the fairing that connects them to the aircraft, is causing the airflow challenge,” per the service. “Boeing has redesigned the fairing and is testing it now to confirm the technical challenge has been overcome. Boeing will then work with the FAA to obtain civil certification of those new fairings.”

The Air Force accepted the first MH-139A helicopter in December, 2019 at Duke Field, Fla., and announced the rotorcraft’s moniker: the “Grey Wolf” (Defense Daily, Dec. 19, 2019).

The helicopters are to replace the service’s 63 Bell [TXT] UH-1N helicopters to provide security and support of the U.S. military’s intercontinental ballistic missile fields, civil search-and-rescue capabilities, airlift support and doomsday VIP transportation.

In response to a question from Sen. Jon Tester (D-Mont.) at a Senate Appropriations Committee defense panel hearing earlier this month, Acting Air Force Secretary John Roth suggested that the helicopters will be in Montana by the fall of 2023 and that the MH-139 delay is minor.