Researchers from the University of British Columbia (UBC) Okanagan School of Engineering have developed a new sensor that detects the accumulation of ice in real time, a development that could improve airliner efficiency and safety.

Developed jointly by a university team that designs microelectronic systems and microwave sensors and another team that studies ice repellant-materials and extreme liquid repellency, the device detects the exact moment water hits the wing of an airplane through to the moment that ice forms on the surface, measuring the thickness of the ice as it increases, without altering the aerodynamic profile of the wing. The teams relied on planar microwave resonator sensors, which are traces of metal placed on a plastic. According to the team, the sensors are sensitive, robust and easy to forge.

Due to their sensitivity and precision, the sensors reportedly work in real-time with the potential for improving the efficiency, cost and speed for ground-based and in-flight de-icing.

"The resonator detected frost formation within seconds after the sensor was cooled below freezing," explained graduate student Benjamin Wiltshire, the first author of the study. "It took about two minutes at -10C for the frost to become visible on the resonator with the naked eye — and that's in one small area in ideal lab conditions. Imagine trying to detect ice over an entire wingspan during a blizzard."

Currently, methods for ice detection are less intricate, typically relying on pilots to visually detect ice on the aircraft wings and subsequently de-icing them in flight. The same sequence of events occurs on the tarmac, where ice accumulation, which has been linked to at least a few airline tragedies, is generally detected by visual inspection. However, visual inspection is prone to human error and environmental changes.

The researchers believe the device could be used by airlines as soon as this winter, with plans for the radiofrequency and microwave technology to eventually be made wireless and contactless.

The research is detailed in the journal Sensors and Actuators B: Chemical.