Ice build up can cause significant problems with aircraft operations and one of the significant challenges with small and medium sized unmanned aircraft is ice detection.
GKN Aerospace have been leading a nine company research project funded by the EU to move away from traditional methods and use optical detectors.
The programme is called ‘On Wings’ or ON-Wing Ice DetectioN and MonitorinG System.
Background from the On Wings website
When an aircraft flies in cold, moist air, especially at low altitudes, ice can form rapidly, both on and behind the leading edge of aerofoils and other structures. The growth of the ice disturbs the local airflow and can radically alter the lift of the aerofoil and hence the handling characteristics of the aircraft. This phenomenon has caused a number of fatal accidents and loss-of-control events, and is a problem that will intensify as increased pressures on airports mean that aircraft will spend much longer in low-altitude holding patterns. Large aircraft use hot gases diverted from the engines to remove ice from flight-critical surfaces, while smaller aircraft sometimes use pneumatic ‘boots’ which expand under pressure to shed the ice layers. These technologies are incompatible with future generations of air transport, in which composite materials will be used extensively. Furthermore, current ice detectors are insensitive, cannot distinguish between ice types and are not co-located with the safety critical zones. Building on electro-thermal de-icing technology now widely used in helicopters, the ON-WINGS project will develop a smart, autonomous, composite electro-thermal de-icing system for fixed-wing, helicopter rotor blade and engine inlet applications.
The traditional methods of hot gas and pneumatic de-icing are not well suited to composite structures so the On Wing sensor aims to demonstrate compatibility with composites.
Using fibre optics embedded inside the sensor it measures reflected light, the return signal being analogous to the type, density and thickness of the ice. This information can then be used to cue electro thermal de-icing systems.
In addition to GKN, the other partners are;
- AOS Technology Ltd UK
- TWT GmbH Science and Innovation DE
- Eurocopter Deutschland GmbH DE
- Wytwornia Sprzetu Komunikacyjnego ‘PZL-Swidnik’ S.A. PL
- GE Aviation Systems Ltd UK
- Sensor Highway Limited UK
Commenting on the recent trials on an Agusta Westland helicopter, Rich Oldfield, Technical Director, GKN Aerospace said
The ON-WINGS project results have huge potential across aviation. Improving the efficiency of ice protection will have positive consequences for operators of all types of aircraft. More efficient, controlled ice protection will lower fuel consumption, increase airframe or aero-engine performance and endurance and lower maintenance needs – as well as reducing critical carbon emissions. All these are vital factors for operators and users of aircraft worldwide.
Clever stuff eh, another British defence company blazing a trail at the leading edge (see what I did there!)