This paper describes the AgustaWestland (AW) experience in the use of the results obtained with the HISS flight tests to support the civil ice clearance for rotorcraft.
The use of the HISS, a US Army CH-47D Chinook fitted with a spray bar system providing a cloud where the helicopter can fly in icing conditions, allows stable and prolonged flight data, conditions extremely difficult to encounter during natural ice flights.
The paper analyses the definition of the HISS test matrix, to optimize the points needed for system development and the points possibly usable during certification, in both normal and failure mode conditions.
It is also shown how the HISS ice campaigns results can be assessed, and how they can be compared to the natural ice flights to validate them.
Finally it is explained how the HISS results can be used, in addition to natural ice flights results, to support the certification.