Boeing recently delivered the first CH-47F Chinook to the Royal Netherlands Air Force (RNLAF), continuing a track record of on-time deliveries to customers. The RNLAF will operate a fleet of 20 CH-47F Chinooks, the newest configuration in use by countries around the world.
“The RNLAF made it clear to us that they need the advanced, proven capability of the CH-47F now,” said Andy Builta, vice president of Cargo & Utility Helicopters and H-47 program manager. “I want to thank our phenomenal team for working hard during a difficult situation to safely deliver these aircraft. This is a reminder to all of us of how important Chinooks are to our customers.”
The 20 CH-47F Chinooks will be a fleet equipped with the same state-of-the-art technology as the U.S. Army, including digital automatic flight controls, a fully-integrated Common Avionics Architecture System (CAAS) glass cockpit, and advanced cargo handling capabilities. The common configuration leads to lower overall life cycle costs.
The RNLAF currently flies a mix of F-model Chinooks with the Advanced Cockpit Management System (ACMS) and CH-47D Chinooks. “It has been a pleasure to work closely together with the U.S. Army and Boeing teams to achieve this milestone,” said Col. Koen van Gogh, Netherlands Defence Materiel Organisation. “The Chinook helicopter is a vital asset for our missions and the in-time delivery certainly supports our operational planning. I salute the Boeing workforce for their continued efforts to make this happen in these troubling times, as well as the U.S. Army officials that helped keep us on track.”
Deliveries to the RNLAF are expected to continue into 2021. Chinooks are currently in service or under contract with 20 international defence forces, including the U.S. Army, U.S. Special Operations Forces and eight NATO member nations.
During late 1956, the United States Department of the Army announced its intention to replace the Sikorsky CH-37 Mojave, which was powered by piston engines, with a new, gas turbine-powered helicopter. Turbine engines were also a key design feature of the smaller UH-1 "Huey" utility helicopter. Following a design competition, in September 1958, a joint Army–Air Force source selection board recommended that the Army procure the Vertol-built medium transport helicopter. However, funding for full-scale development was not then available, and the Army vacillated on its design requirements. Some officials in Army Aviation thought that the new helicopter should be operated as a light tactical transport aimed at taking over the missions of the old piston-engined Piasecki H-21 and Sikorsky H-34 helicopters, and be consequently capable of carrying about 15 troops (one squad). Another faction in Army Aviation thought that the new helicopter should be much larger, enabling it to airlift large artillery pieces and possess enough internal space to carry the new MGM-31 "Pershing" missile system.
Sikorsky CH-37 Mojave
During 1957, Vertol commenced work upon a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. During June 1958, the U.S. Army awarded a contract to Vertol for the acquisition of a small number of the rotorcraft, giving it the YHC-1A designation. As ordered, the YHC-1A possessed the capacity to carry a maximum of 20 troops. Three underwent testing by the Army for deriving engineering and operational data. However, the YHC-1A was considered by many figures within the Army users to be too heavy for the assault role, while too light for the more general transport role. Accordingly, a decision was made to procure a heavier transport helicopter, and at the same time, upgrade the UH-1 "Huey" to serve as the needed tactical troop transport. The YHC-1A would be improved and adopted by the Marines as the CH-46 Sea Knight in 1962. As a result, the Army issued a new order to Vertol for an enlarged derivative of the V-107, known by internal company designation as the Model 114, which it gave the designation of HC-1B. On 21 September 1961, the preproduction Boeing Vertol YCH-1B made its initial hovering flight. During 1962, the HC-1B was redesignated the CH-47A under the 1962 United States Tri-Service aircraft designation system; it was also named "Chinook" after the Chinook people of the Pacific Northwest.
The CH-47 is powered by two Lycoming T55 turboshaft engines, mounted on each side of the helicopter's rear pylon and connected to the rotors by drive shafts. Initial models were fitted with engines rated at 2,200 horsepower each. The counter-rotating rotors eliminate the need for an antitorque vertical rotor, allowing all power to be used for lift and thrust. The ability to adjust lift in either rotor makes it less sensitive to changes in the centre of gravity, important for the cargo lifting and dropping. While hovering over a specific location, a twin-rotor helicopter has increased stability over a single rotor when weight is added or removed, for example, when troops drop from or begin climbing up ropes to the aircraft, or when other cargo is dropped. If one engine fails, the other can drive both rotors. The "sizing" of the Chinook was directly related to the growth of the Huey and the Army's tacticians' insistence that initial air assaults be built around the squad. The Army pushed for both the Huey and the Chinook, and this focus was responsible for the acceleration of its air mobility effort.
Lycoming T55 turboshaft
Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system, and improved avionics. The latest mainstream generation is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower Honeywell engines.
A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires, and supporting petroleum extraction operations. In December 2006, Columbia Helicopters Inc. purchased the type certificate of the Model 234 from Boeing. The Chinook has also been licensed to be built by companies outside the United States, such as Agusta (now AgustaWestland) in Italy and Kawasaki in Japan.