Why to install a Fly-By-Wire control system on the NH90 helicopter and what are the advantages ?
The reason is simple: as the threat is becoming more and more sophisticated and difficult, the future generation helicopter should allow the pilot to concentrate himself entirely on the mission he has to perform in a very limited time and in any operational condition. It should not request him to devote the biggest part of his effort on the flight, as it is happening with the today helicopter generation. As the helicopter is by nature a very unstable platform difficult to master, in the present helicopters the pilot is helped both by mechanical devices (i.e. control cross couplings through the mixing units) and electronic systems (SAS, SCAS, autopilots). All of them give a valuable support to the pilot but some aspects are still marginal and to be improved to achieve "Level 1 Handling Qualities within the Operational Flight Envelope" as required for NH90.
Traditional flight controls and especially mixing unit devices are mechanically complex and heavy, mechanical control laws are the result of several compromises thus preventing the necessary output control precision. On the other hand present autopilots are lacking of the necessary control authority to be able to take the requested action, in the requested time, in all the flight envelope.

The NH90 Fly-By-Wire solution allows :
- the reduction in weight and complexity of the flight control system including the elimination of the control mixing units,
- the optimisation of the handling qualities throughout the whole flight envelope with helicopter responses tailored to the mission tasks requested ,
- the improvement of vulnerability and safety, through a high redundancy of the system (four independent lines for data transfer with four control processing units - digital and analogic - and capability to remain operationally efficient irrespective of the failure type),
- intrinsic growth potential to implement new mission tasks and new advanced control law concepts including "carefree handling" features.

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