Northrop Grumman will deliver the first pair of South Korea’s four RQ-4B Block 30 Global Hawk unmanned aircraft in 2018, and the second pair in 2019.

Speaking with Flightglobal at the Seoul International Aerospace & Defense Exhibition (ADEX), Global Hawk vice-president Michael Jaggers said the first of Seoul's aircraft is already under construction.

Early 2017 will see South Korean pilots and maintainers also start to train on the aircraft. The nation’s $657 million acquisition of the high-altitude, long-endurance type was announced in December 2014, with Northrop also to provide two ground control stations.

It had been planned for a US Air Force Global Hawk to attend the Seoul show, but operational requirements prevented this.

Northrop also used the show to announce the appointment of two local suppliers for the Global Hawk programme: Firstec and Korea Jig and Fixtures (KJF). As part of the US company's offset obligations, Firstec will make wire harnesses for the unmanned aircraft, while KJF will build precision machine parts.

South Korea’s Global Hawks will carry a “multi-intelligence” payload that includes synthetic aperture radar and a long-range electro-optical/infrared sensor. It is expected that the aircraft will be used in close collaboration with the USA, which also operates various variants of the aircraft.