PAUL LEWIS / WASHINGTON
Research funding is being channelled from FTR towards unmanned air vehicles research
The US Army is beginning to pay closer attention to further growth developments of the Boeing CH-47 Chinook helicopter as a nearer-term solution to meeting its heavy-lift requirements. Department of Defense science and technology funding is being diverted away from an all-new Future Transport Rotorcraft (FTR) and funnelled into unmanned air vehicle research.
With FTR on the back burner, US Army Aviation planners are having to look at alternatives including a follow-on programme to the current CH-47F Improved Cargo Helicopter (ICH). Designated the CH-47X, this would have a 30,870kg (68,000lb) or higher maximum take-off weight, compared with the CH-47D/F's 22,680kg.
Options being considered are adding funding around fiscal year 2012 (requiring a FY08 decision) to remanufacture into CH-47Fs, the 131 Ds that are not part of the ICH programme, or developing the helicopter further, according to Gen Joe Bergantz, head of the army's aviation programme executive office. The first of 300 modernised CH-47Fs, along with 36 MH-47G special forces helicopters, will be delivered in 2004.
Much will hinge on the final weight of the army's Future Combat System (FCS) armoured vehicle, which will form the backbone of its fighting force. Earlier FTR studies had worked on the assumption that FCS would be in the 20t class. The CH-47D can carry around 12,700kg, but over a limited range. The improved 3,100kW (4,170shp) Honeywell T55-714 will provide the CH-47F with an improved margin particularly in hot and high conditions.
At the envisioned CH-47X operating weights, a new engine in the 4,470kW class would be needed. Options include a version of the Rolls-Royce T406 that powers the Bell Boeing V-22, or a more fuel efficient, new powerplant developed from the Joint Turbine Advanced Gas Generator Phase III programme. Either option would require all new dynamic components, including four-blade rotors.
Boeing is pushing to reduce Chinook's price to keep it competitive. A CH-47SD costs $30-32 million. The forward fuselage section 41 could be digitally redesigned and built using lean technology.
Source: Flight International
