NH 90 HELICOPTER FLY-BY-WIRE FLIGHT CONTROL SYSTEM

The NH 90 is a twin engine, multi-role naval and tactical transport helicopter in the 9 ton class developed in cooperation between France, Germany, Italy and The Netherlands. This helicopter is scheduled to be in service in 2002 into the four participating nations. Due to stringent requirements set on this aircraft, a Fly-by-wire control system has been selected. This paper traces the main features which have lead to the present definition of the FBW control system and describes the architecture and control laws of solely the Primary Flight Control System (PFCS). Although Automatic Flight Control System (AFCS) is hosted by the FBW control system, level 1 handling qualities are obtained with AFCS OFF. Piloted simulations has demonstrated level 1 with only PFCS ON. The system is in ground test phase and first flight is expected soon.