The Boeing Chinook is a tandem rotor helicopter operated by the Royal Air Force (RAF). A series of variants based on the United States Army‘s Boeing CH-47 Chinook, the RAF Chinook fleet is the largest outside the United States. RAF Chinooks have seen extensive service including fighting in the Falklands War, peace-keeping commitments in the Balkans, and action in the Iraq and Afghanistan wars.
The Chinook HC2 aircraft, normally based at RAF Odiham, provides heavy-lift support and transport across all branches of the British armed forces, and is supported by the smaller, medium-lift helicopters such as the AgustaWestland Merlin HC3 and the Westland Puma HC1, based at RAF Benson and RAF Aldergrove.
In March 1967 an order was placed for fifteen Chinook HC1s, standing for Helicopter, Cargo Mark 1, for the Royal Air Force to replace the Bristol Belvedere. This original HC1 variant was to be based on the CH-47B but the order was cancelled in a review of defence spending in November 1967. UK Chinook procurement ambitions were revived in 1978 with an announced requirement for a new heavy-lift helicopter to replace the Westland Wessex. Thirty Chinooks were ordered at a price of US$200 million. These helicopters, comparable to the CH-47C with Lycoming T55-L-11E engines, were again designated Chinook HC1, and entered service in December 1980. Eight more HC1s were delivered from 1984 to 1986 with the CH-47D’s Lycoming T55-L-712 turboshafts.
The replacement of the HC1’s metal rotor blades with aluminium and glass fibre composite rotor blades saw these aircraft designated Chinook HC1B. All surviving aircraft were later returned to Boeing and updated to the Chinook HC2 standard for further service within the RAF.
The US Army’s next generation Chinook, the CH-47D, entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, redundant and improved electrical systems, an advanced flight control system (FCS) and improved avionics. The RAF returned their original HC1s to Boeing for upgrading to CH-47D standard, the first of which returned to the UK in 1993. Three additional HC2 Chinooks were ordered with delivery beginning in 1995. Another six were ordered in 1995 under the Chinook HC2A designation; the main difference between these and the standard HC2 was the strengthening of the front fuselage to allow the fitting of an aerial refuelling probe in future. One Argentine CH-47C was captured during the Falklands War, and used by the RAF as a training aid. The rear fuselage was later used to repair a crashed RAF Chinook in 2003.In 2006, the retirement dates for the HC2 and HC2A fleets were scheduled for 2015 and 2025 respectively, but if planned upgrades are made both types could expect to be flying until 2040.
Eight Chinook HC3s were ordered in 1995 as dedicated special forces helicopters, which were intended to be low-cost variants of the US Army’s MH-47E. The HC3s include improved range, night vision sensors and navigation capability. The eight aircraft were to cost £259 million and the forecast in-service date was November 1998. Although delivered in 2001, the HC3 could not receive airworthiness certificates as it was not possible to certify the avionics software. The avionics were unsuitable due to poor risk analysis and necessary requirements omitted from the procurement contract. The Times claimed that the Ministry of Defence planned to perform software integration itself, without Boeing’s involvement, in order to reduce costs. While lacking certification, the helicopters were only permitted to fly in visual meteorological conditions and subsequently stored in climate controlled hangars.
After protracted negotiations to allow them to enter service, Air Forces Monthly reported in November 2006 that the Defence Aviation Repair Agency would likely receive a contract to install the Thales “TopDeck” avionics system on the Chinook HC3s. However, the Ministry of Defence announced in March 2007 that this so-called “Fix to Field” programme would be cancelled, and instead it would revert the helicopters’ avionics to Chinook HC2/2A specification. The programme was estimated to cost £50–60 million. In June 2008, the National Audit Office issued a scathing report on the MoD’s handling of the affair, stating that the whole programme was likely to cost £500 million by the time the helicopters enter service. On 6 July 2009 the first of the eight modified Chinook HC3s made its first test flight at MoD Boscombe Down as part of the flight testing and evaluation phase of the HC3 “reversion” program.
Chinook HC4 / HC5 / HC6
A programme to upgrade 46 Chinook HC2, HC2A and HC3 helicopters was initiated in December 2008. Called Project Julius, it includes new digital flight deck avionics based on the Thales TopDeck avionics suite, comprising new multifunction displays, a digital moving map display and an electronic flight bag, installation of a nose-mounted FLIR detector, and upgrading the engines to the more powerful T55-714 standard. Upgraded HC2, HC2A and HC3 aircraft will be redesignated HC4, HC4A and HC5 respectively, and deliveries are expected to commence in 2011. The first conversion, a Chinook HC4, first flew on 9 December 2010. Initial operating capability status was reached in June 2012 with seven aircraft delivered.
The Chinook HC6 designation has been assigned to the 24 (later reduced to 14) CH-47F-derived Chinooks ordered in 2009. These will have Boeing digital flight-control systems and are expected to be delivered during 2013. Three had been delivered by June 2014
- Role: Transport Helicopter
National Origin: Multi-National
Introduction: 1980 with RAF
Status: Active Service
- Primary Users: Royal Air Force
Unit cost: £60.1m (HC6, 2012)
Manufacturer: Boeing Rotorcraft Systems
Numbers Built: 58
Developed From: Boeing CH-47 Chinook