For the first time, a prototype autonomous fighter jet being developed by Boeing has appeared in the USA.

The US defence aerospace giant revealed an MQ-28 Ghost Bat on 25 May at a Boeing facility near St. Louis, Missouri – where the company’s defence unit is headquartered.

Boeing Defense, Space & Security (BDS) is developing the Ghost Bat in partnership with the Royal Australian Air Force (RAAF) and Boeing’s secretive Phantom Works aircraft development division.

Design and testing work on the pilotless jet had until now been conducted in Australia. BDS had displayed the Ghost Bat publicly for the first time in February at the Avalon International Airshow near Melbourne, Victoria.

Officials at Avalon, speaking on the condition of anonymity, told FlightGlobal at the time that an MQ-28 had been sent to the USA for testing with the US Air Force (USAF).

While flight testing for the type has been ongoing in Australia, this marks the first time an example of the revolutionary aircraft has been seen publicly outside its home country.

Boeing officials with Phantom Works say only that they have brought the MQ-28 to St. Louis for testing. The site is also where Boeing has been developing another autonomous jet aircraft – the US Navy’s MQ-25 Stingray autonomous refueller.

Pete Kunz, the head of Phantom Works, confirms the two aircraft do share some common technologies. Production work on four MQ-25s is currently underway in St. Louis, with nine aircraft under contract.

The navy plans to buy some 70 Stingrays, with the fleet reaching initial operational capability in 2026, according to Boeing.

Boeing is also constructing a new production line across the Mississippi River in Illinois that will serve as the eventual full-rate production centre for the autonomous in-flight refueller.

Unlike the MQ-25, which was specifically contracted to replace the carrier-based in-flight refuelling mission currently filled by the Boeing F/A-18 Super Hornet strike fighter, the MQ-28 is apparently designed without a specific mission in mind.

Boeing is revealing little about the Ghost Bat’s development process. However, officials with Phantom Works tell FlightGlobal they envision the MQ-28 as a general autonomous jet aircraft that can be tailored to fit the interests of future customers.

“MQ-28A Ghost Bat is a sovereign autonomous air vehicle designed to operate as part of an integrated system of crewed and uncrewed aircraft and space-based capabilities,” the Australian government said in a defence strategic review published in April. “MQ-28A is intended to be an attritable platform, which costs less than a crewed platform, and can be replaced rapidly,” the report adds.

Both the USN and the USAF are betting heavily on cheap, pilotless aircraft as a centrepiece of their future aviation fleets. The navy eventually wants 60% of its carrier air wings to be made up of uncrewed aircraft.

Meanwhile, the USAF is planning to heavily incorporate so-called Collaborative Combat Aircraft (CCA) into its recently-launched sixth-generation fighter development programme. Such autonomous craft would support human aviators with a range of potential capabilities, including precision munition strikes and electronic warfare.

Currently, the USAF and the USN are conducting tests with the Kratos XQ-58 Valkyrie autonomous combat jet. The presence of the Ghost Bat on American soil may indicate a new entrant into what is expected to be a lucrative and competitive CCA development space.

Any large-scale production or acquisition of the MQ-28 by Washington would have to be approved under Canberra’s export rules, according to Boeing. While the company would not disclose the status of any such talks, Boeing’s vice-president of air dominance Steve Nordlund does not expect any issues.

“We don’t see any major hangups,” he said on 25 May.

He adds that Boeing expects wide interest in the MQ-28 beyond just Australia and the USA.

“I think MQ-28 has a market that is not bound to those two countries.”