BOEING HELICOPTER will flight-test later this year a CH-47 Chinook with a dynamically tuned fuselage, to reduce vibration, in the first step towards a possible US Army upgrade programme later this decade.

The company will complete the present US Army Chinook modernisation programme by the end of 1995, with delivery of the last of seven ex-Australian aircraft upgraded to the current CH-47D standard. The last new-build MH-47E special-operations Chinook will be delivered to the Army in April, Boeing says.

No plans exist to replace the Chinook, so the Army is studying possible upgrades. The tuned fuselage is designed to reduce vibration from the present three-blade rotors and so improve avionics reliability. Plans to upgrade the CH-47 with four-blade rotors have been deemed too expensive, the manufacturer says.

Other upgrade options being studied include up-rated AlliedSignal T54-714 engines, providing 10% more power and burning 3% less fuel, to increase payload, inlet particle separators, improved cargo-handling system and digital databus. Redesign of the aft-rotor pylon to speed removal and re-attachment for air transport in the Lockheed C-141 is also under consideration, Boeing says.

Source: Flight International