The US Defense Security Cooperation Agency (DSCA) has announced the approval by the US State Department for the sale of 16 Boeing CH-47 (Extended Range) Chinooks to the UK.

The October 19 notification says the sale is valued at US$3.5bn (A$4.9bn) and would include four spare T55-GA-714A engines as well as a range of equipment including common missile warning systems, GPS inertial navigation units, RF countermeasures sets, radars, EO/IR sensors, mini-guns and mounts, and communications suites. The sale would also include spares, training, technical publications, maintenance support, ground support equipment, and safety and airworthiness certifications.

On face value, the new aircraft appear to be specified similarly to the US Army’s MG-47G special operations configuration with the large sponson fuel ‘big tanks’, and it is unclear if the aircraft will be in addition to the UK’s current fleet of CH-47s, or will replace some of the older aircraft in service.

The RAF operates 60 Chinooks of various models, including the HC4, HC5 and HC6/6A models. The HC4 is an upgraded CH-47D with a Thales TopDeck avionics suite. They were originally upgraded from early HC1As (CH-47B/Cs), and some are due to be further upgraded with a Digital Automatic Flight Control System and redesignated as HC6As.

The HC5 is the designation given to an upgrade of the HC3 model which is essentially a ‘big tank’ CH-47SD ordered in the late 1990s but which were delivered directly to storage due to certification issues. The HC3s were eventually upgraded with the TopDeck avionics and finally entered service from 2011.