Maritime patrol Nine Boeing Poseidon MRA1 were ordered by the Government in November 2015 in its Strategic Defence and Security Review for surveillance, anti-submarine and anti-surface ship warfare, filling a capability gap in maritime patrol that had been left since the cancellation of the BAE Systems Nimrod MRA4 programme in the 2010 SDSR. On 13 July 2017, it was announced that No. 120 Squadron and No. 201 Squadron, both former Nimrod MR2 squadrons, would operate the Poseidon and be based at RAF Lossiemouth. No. 120 Squadron stood up on 1 April 2018, with No. 201 Squadron reforming on 7 August 2021. No. 54 Squadron acts as the OCU for the Poseidon fleet. The first production Poseidon MRA1 ZP801 made its initial flight on 13 July 2019. ZP801 arrived at Kinloss Barracks, the former home of the Nimrod, on 4 February 2020, filling a decade long gap in maritime capability. The Poseidon was declared combat ready in April 2020. The Poseidon carried out its first operational mission on 3 August 2020, when the Russian warship Vasily Bykov was tracked. A Poseidon MRA1 arrived at RAF Lossiemouth for the first time in October 2020. The ninth, and final Poseidon arrived at RAF Lossiemouth on 11 January 2022. Air mobility No. 99 Squadron operate eight Boeing C-17A Globemaster III in the heavy strategic airlift role from RAF Brize Norton, Oxfordshire. Four C-17A were originally leased from Boeing in 2000, These four were subsequently purchased outright, followed by a fifth delivered on 7 April 2008 and a sixth delivered on 11 June 2008. The MOD said there was "a stated departmental requirement for eight" C-17s and a seventh was subsequently ordered, to be delivered in December 2010. In February 2012 the purchase of an eighth C-17 was confirmed; the aircraft arrived at RAF Brize Norton in May 2012. Shorter range, tactical-airlift transport is provided by the Lockheed Martin C-130J Hercules, known as the Hercules C4 (C-130J-30) and Hercules C5 (C-130J) in RAF service, based at RAF Brize Norton and flown by No. 47 Squadron. Twenty-five C-130Js were originally ordered in December 1994 (15 C4s and ten C5s), the first Hercules C4 to be delivered was ZH865 in August 1998, with the first Hercules C5 (ZH881) in May 1999. The 2010 SDSR called for the retirement of the Hercules fleet by 2022, with the 2015 SDSR amending this to maintaining the fourteen Hercules C4s until