Improving the flight safety minimizing the need of flight trials

Authors
Bottarini Claudio Piercarlo, AgustaWestland a Finmeccanica Company, Italy
Buschini Agostino, AgustaWestland a Finmeccanica Company, Italy

Abstract

Development of modern avionics systems, due to their complexity, implies a very huge test activity to be performed partially on ground and partially in flight.

Finding a way to reduce the part of tests to be performed in flight would have an important, even if indirect, impact on flight safety due to the intrinsic risk of flight.

This goal has been reached by AgustaWestland establishing a specific testing methodology that foresees the use of very powerful test benches with the aim to increase the amount, deepness and coverage of the on ground testing at all levels (equipment, system and overall integrated avionics system level).

Output of such on ground activity, that clearly requires significant effort in term of time and resources, is a “bug free”, or at least “bug known”, avionics system, that can be installed on the helicopter for the in flight testing phase, which can be only relevant to function not testable on ground and, mainly, to avionic subsystem performance evaluation.

Advance knowledge of problems, implies also minimization of “wasted” flight hours, since crew will not spend time dealing with unknown malfunctions met during flight, improving in this way the flight effectiveness and reducing the crew workload and stress.

Agustawestland experience in integration and validation (I&V) of complex avionics system began in 1980 with the AW129 Mangusta attack helicopter; testing methodology has been progressively refined along years taking also benefit of the great evolution of Information Technology (I&T) tools occurred in the last 2 decades.

The state of the art benches are used in all AgustaWestland programs such as, for example, the NH90 helicopter for which AW has the full responsibility of developing and integrating the mission systems of the naval variant (NFH).

A raw figure to understand the benefit reached with such testing methodology can be the percentage of problems detected during flight test activity for the first qualified NH90 NFH variant (Netherland Navy): only 1%!

This paper describes Agustawestland’s thirty-year experience and, as example, presents the process followed from the design and development up to the qualification of the Tactical Navigation System (TACNAV) of the NH90 NFH variant.

Possible further improvement for near future are also briefly described.