Country of origin:

United States of America

Description:

Heavy-lift helicopter

Power Plant:

Two 2,797 kw (3,750 shp) Lycoming T55-L-712 turboshafts

Specifications:

History:

Designed to compete in a US Army competition for an aircraft to vertically lift a payload of 1,814 kg (4,000 lb) internally, or 7,258 kg (16,000 lb) externally, the Boeing Model 114 (designated YHC-1B by the US Army) made its first flight on 21 September 1961. Subsequently the type entered production for that service as the CH-47A. These first production examples were powered by 1,641 kw (2,200 shp) Lycoming YT55-I-5 engines, with the first being delivered on 16 August 1962.

The design was developed and refined through a number of variants, resulting in machines with greater power and lift capability. The type was obtained for the heavy-lift role by a number of air forces, including those of Australia, Canada, Iran, the United Kingdom (as the HC Mk1) and Italy.

Thirty-three examples were ordered for the RAF, with deliveries commencing in December 1980. This model contained some features of the CH-47D and the Canadian CH-47, but provision was made for glass-fibre/carbon-fibre rotor blades. A commercial variant, the Model 234 Chinook, also appeared fitted with two 3,040 kw (4,075 shp) Avco Lycoming AL5512 turboshafts. The first example of this new model was flown on 19 August 1980. First deliveries were to British Airways Helicopters, which used the type on oil-rig support work in the North Sea.

Most of the Chinooks licence built in Italy were for the Italian Air Force, but examples were also supplied to the air forces of Iran, Libya and Morocco.

The type has continued to be developed and variants produced have included the CH-47B, which was basically a CH-47A with up-rated 2,126 kw (2,850 shp) T55-L7C turboshafts, re-designed rotor blades and other refinements.

The first of two prototypes was flown in October 1966. The CH-47C had 2,797 kw (3,750 shp) T55-L-11C turboshafts, a strengthened transmission system to take the extra power, a maximum take-off weight increased to 22,680 kg (50,000 lb), and an increase in fuel capacity. The first CH-47C was flown on 14 October 1967. During the Vietnam War four Chinooks known as the ACH-47A were equipped with armour and armament, including a grenade launcher in the nose, and a number of 12.7 mm (0.5 in) machine guns. Three were evaluated but no further examples were built.

The next variant was the CH-47D, which resulted from a modernisation program applied to the CH-47A, CH-47B and CH-47C models in US Army service. The first conversion, carried out on a CH-47A, was flown on 11 May 1979, and a program was put in train to convert earlier models. Modernisation included the installation of 3,357 kw (4,500 shp) Avco Lycoming T55-L-712 turboshafts, an APU and more advanced equipment.

On 19 August 1970 the Australian Government ordered 12 Boeing CH-47C Chinooks (Boeing Model No BV-165) helicopters. However, formal agreement was withheld at that time until engine overheating problems were solved. The contract was signed in March 1972, the aircraft to provide tactical troop movements for an army company group, and being capable of logistic support, aerial crane service, aero-medical evacuation, and air-sea-rescue in tactical operations. The aircraft was capable of landing on water to pick up swimmers through the rear hatch, and, although not fitted with floats, it could rest on the water with the engines running for this purpose.

The Chinooks A15-001 to A15-012 (c/ns E-001 to E-012 – US Army serials 73-12970 to 73-12981) were delivered to No 12 Squadron at Amberley, QLD from ‘HMAS Melbourne’ on 28 April 1974. For a period six were put into storage at Amberley due to Government budget restrictions.

A number of interesting heavy-lift operations have been carried out by the RAAF Chinooks. These have included transporting a Ford Tri-Motor, which force landed in New Guinea during World War II when evacuating troops, to Port Moresby, PNG for a museum; transporting an RAAF Caribou which crashed in New Guinea; lifting two Grumman Trackers of the RAN from ‘HMAS Albatross’ to ‘HMAS Melbourne’ off the NSW coast and then from the latter to Bankstown Aerodrome for reconstruction after the disastrous fire at the naval base which almost destroyed the Navy’s entire Grumman Tracker force on 4 December 1976; and recovering a number of Douglas Bostons and Havocs from New Guinea for restoration for the RAAF Museum and a New Guinea museum.

Two Boeing CH-47Cs were lost in service: A15-001 at Perseverance Dam, QLD on 26 June 1975 and A15-011 at Amberley, QLD on 26 June 1975. The former was issued to the Amberley fire service as a training aid; and the latter was repaired by No 3 Aircraft Depot, returning to service in 1981.

In 1989 the Australian Government announced the withdrawal of the fleet of Chinooks and disbandment of No 12 Squadron, this occurring on 30 June that year. The aircraft were stored and efforts made to sell them but to no avail. In 1991 the Defence Minister announced a deal whereby seven would be sold to the US Army and four would be up-graded to CH-47D standard. The latter (A15-002, A15-003, A15-004 and A15-006 – c/ns E-002 to E-004 and E-006) were rebuilt by Boeing and returned to service with No 5 Aviation Regiment at Townsville, QLD in 1995 with new serials (A15-102, A15-103, A15-104 and A15-106). In 2000 two further CH-47Ds were obtained from the US (A15-201 – c/n M.4023 –ex N2138T and A15-202 – c/n M.4024 – ex N2142V) to make a total of six aircraft, these latter two being delivered to No 5 Aviation Regiment at Townsville in February 2000.

In 1995 Australian Army Chinooks were deployed to Kuwait to assist during the Coalition Forces invasion of Iraq. In 2006 two CH-47Ds were deployed to Afghanistan to support Australias Special Forces Task Group and coalition forces.

In late 2005 / early 2006 the Australian Chinooks underwent an up-grade as part of a rapid acquisition project to enhance the electronic warfare systems, communications, ballistic protection and medivac capabilities.

In later times in the United States the military services have been putting their CH-47Ds through a re-manufacturing program to bring them up to CH-47F specification. This involved the installation of Lycoming T55-GA-714A engines, improved crash-worthiness, integrated digital avionics, and an air-to-air refuelling probe. As the six Australian CH-47Ds commenced to receive an engine up-grade in late 2006, and a mid-life upgrade in the 2007-2010 timeframe, it was mooted these machines would be put through the US up-grade program and perhaps a further six CH-47Fs be obtained to increase the capability of the fleet. However, in early 2010 the Australian Government announced seven CH-47Fs would be obtained to replace the CH-47Ds, the first to enter service in 2014 and all to be delivered under Air 9000 5C by 2017.

One Chinook (A15-102) was lost when it crashed during operations in Afghanistan on 30 May 2011. It crashed in difficult country, was deemed not to be recoverable, and was destroyed on site. In December 2011 the Australian Government announced a further two would be obtained, both new, one being an extra machine and the other to replace A15-102.

On 17 April 2015 a Boeing CH-47D Chinook A15-016 named ‘Life’s A Beach’, which was originally built as a CH-47C and was delivered to the RAAF in 1974 as A15-006, later rebuilt as CH-47D in the United States, and which served in the Persian Gulf region with the Rotary Wing Group in Afghanistan, was retired and flown to the RAAF Museum at Point Cook, VIC for display.

Also in April 2015 the Australian Army took delivery of the first two CH-47Fs under Air 9000 Phase 5C, a total of seven being on order to replace the existing fleet of seven CH-47Ds, to be operated by No 5 Aviation Regiment from RAAF Base, Townsville. The remaining five were delivered by August 2015 and at the same time two CH-47F flight simulators were placed in service at Townsville. The purchase was through the United States Foreign Military Sales program, maintenance for the new helicopters being through a partnership between Boeing Defence Australia and BAE Systems. Serials for the CH-47Fs were A15-301 to A15-307.

In mid 2021 thr Australian Army took delivery of two new CH-47F Chinooks, with two more to be delivered soon thereafter making the total number in the fleet 14 aircraft.