Two General Atomics Aeronautical Systems MQ-9 Reaper unmanned air vehicles have demonstrated the system’s ability to track missiles, during ballistic defence testing in Hawaii.

The test was carried out in late June, during the Pacific Dragon exercise at the Pacific Missile Range Facility on Kauai: a multilateral ballistic missile defence training event involving the US Navy, the Japan Maritime Self-Defence Force and the South Korean navy.

General Atomics says the specific Reaper element of the testing was carried out under a contract awarded by the US Missile Defence Agency (MDA), and involved the UAVs using their Raytheon Multi-Spectral Targeting System-B electro-optical/infrared turret to detect and track ballistic missile targets.

“The test provided valuable data in our ongoing effort to develop an effective airborne missile defence capability,” Linden Blue, the chief-executive of the company, says.

The MDA is exploring the use of UAVs in missile defence as a more flexible and low-cost option for intercepting ballistic weapons.

“By leveraging unmanned aerial vehicles and space assets for pervasive over-the-horizon sensor netting, the engagement zone of current [Raytheon] Standard Missile-3 interceptors can be extended to the pre-apogee portion of a missile's trajectory,” the agency says.

“Forward-basing TPY-2 radars come with diplomatic challenges and significant O&S [operation and sustainment] costs, making the use of current overhead persistent infrared and less expensive operations of Predator UAVs an appealing near-term option.”

Meanwhile, General Atomics has been awarded a contract worth $371 million by the US Department of Defense to provide 30 Reapers under 2014 and 2015 fiscal year funding, with deliveries to occur until May 2019.

The USAF had an inventory of 93 Reapers as of September 2015, the service says. The type has also been acquired or ordered by foreign military customers France, Spain and the UK.