Helicopter flight controls blades collectively ("i.e.," all at the same time) and independent of their position. Therefore, if a collective input is made, all the blades change equally, and as a result, the helicopter increases or decreases its total lift derived from the rotor. In level flight this would cause a climb or descent, while with the helicopter pitched forward an increase in total lift would produce an acceleration together with a given amount of ascent. The collective pitch control in a Boeing CH-47 Chinook is called a "thrust control", but serves the same purpose, except that it controls two rotor systems, applying
Joint Helicopter Support Unit in Sept 2009. www.jhsu.co.uk Joint Helicopter Support Unit The Joint Helicopter Support Unit (JHSU) was a joint organisation of the British Army and the Royal Air Force, located in RAF Odiham. It was formed in July 1982, following the introduction of the Chinook HC MK1 Helicopter. Personnel were drawn from the Royal Corps of Transport (RCT) and Royal Army Ordnance Corps (RAOC) (both now amalgamated into the Royal Logistic Corps (RLC)) plus the Royal Corps of Signals and the Royal Air Force (RAF). The JHSU became the Joint Helicopter Support Squadron (JHSS) following its merger with the RAF Mobile Air