The B1-B and B-2 aircraft flew from Guam and Diego Garcia respectively, and operated over Delamere, Bradshaw and Mount Bundey training areas during August.

While they did not land in the NT, it is planned in years to come they will be able to use the Tindal RAAF Base once the upgrades there are complete.

The activity saw the United States aircraft integrate with the Australian Army and US Marine Rotational Force - Darwin, providing a highly advanced training opportunity.

The US aircraft exercised both live and inert munitions on the training areas allowing the Australian and US forces the opportunity to practice their skills in both traditional and modern forms of target location, strike confirmation, and damage assessment.

While the B1-B and B-2 aircraft did not land in Australia, they were supported by US Air Force air-to-air refuelling aircraft that flew out of RAAF Base Darwin.

Tindal's runway is being extended by 610 metres to become 3.3 kilometres long, part of the $1.6 billion upgrade to allow big refueling aircraft to use the base, but also to cater for the big US bombers.

The runway shoulders are being widened and strengthened.

There will be work "re-aligning, extending and widening the parallel taxiway for heavy aircraft movements".

Two new operational readiness platforms will be built at each end of the runway, upgrading an existing secondary taxiway to accommodate larger aircraft and upgrading the airfield stormwater drainage system.

A new fuel farm will be built with two giant steel tanks to be encased in concrete and earth to contain six million litres of fuel, that's about the capacity of six Olympic-sized swimming pools.

The aircrews of the refuelling aircraft in this latest exercise were managed under strict Federal and Territory COVID-19 requirements while transiting through Australia.

The scenario focused on a small naval expeditionary force's ability to rapidly deploy, integrate with foreign partners, coordinate airstrikes and call for close air support on targets within contested environments.

Marine Rotational Force - Darwin and Australian Army joint terminal attack controllers worked alongside Australian Army Tiger armed reconnaissance helicopters and Marine Corps RQ-21A Blackjacks to identify and surveil notional targets.

The staffs coordinated airstrikes from US Air Force B-1B Lancers with the 37th Expeditionary Bomb Squadron and B-2 Spirit stealth bombers with the 393rd Bomb Squadron, before passing those same aircraft to tactical units to conduct close air support.

Australian involvement included Tiger Armed Reconnaissance Helicopters and joint terminal attack controllers from Darwin based Army units.

The ability of both militaries to successfully complete this training during the COVID-19 pandemic is a demonstration of the resilience of our long-standing alliance cooperation.

US bombers have been visiting Australia since the 1940s, with the first B-1B Lancer arriving in 1995.

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