US airframer Boeing has completed assembly of the first production-model MH-139 Grey Wolf helicopter.
Boeing revealed the milestone on 26 January, saying it completed assembly on the first operational example of the new US Air Force (USAF) nuclear-site security helicopter in late December.
The aircraft made its maiden flight shortly after as part of a flight-test programme.
“We are committed to advancing this programme and have achieved another significant milestone with the first production aircraft,” says Azeem Khan, MH-139 programme director at Boeing. “This accomplishment positions us to complete outstanding testing and move closer to delivering this critical capability to the US Air Force.”
The Grey Wolf is intended to replace the USAF’s fleet of Bell UH-1Ns currently providing security at the USA’s nuclear-armed intercontinental ballistic missile sites scattered throughout the interior of North America.
The USAF ultimately plans to acquire 84 of the type, which is based on the Leonardo Helicopters AW139 civil airframe.
Leonardo produces the helicopter in Philadelphia, while Boeing, acting as prime contractor, is responsible for militarising the aircraft and delivering them to the USAF.
Flight testing is taking place at the Boeing site in Philadelphia, according to Boeing Defense, Space & Security chief executive Ted Colbert.
“This advanced aircraft boasts a 50% faster cruise, 50% extended flight range and a noteworthy 5,000-pound lift capacity compared to its predecessor,” Colbert said in a 26 January LinkedIn post.
“Its state-of-the-art avionics system and optimal design underscore our commitment to maximum operational efficiency,” he adds.
The MH-139 is unique as a military helicopter tasked with operating in domestic airspace, which requires Boeing to obtain US Federal Aviation Administration (FAA) type certification.
That has proved to be a greater challenge than anticipated, as the FAA had no previous experience evaluating some of the aircraft’s military flight systems, such as its identification friend-or-foe transponder.
Boeing says it continues the required FAA certification testing and expects to begin delivering production aircraft to the air force in 2024.