Pilots, drivers, and automated safety systems in cars and airplanes can be alerted to environmental hazards by new types of optical and microwave sensors my team and I developed. Ice, snow and water on roads make them slippery, causing around 20% of weather-related car crashes each year, while ice build-up on airplanes causes roughly 10% of all fatal air carrier crashes by interfering with aerodynamics, airspeed sensors, and flight controls.

Icy, snowy, and wet roads cause accidents that kill more people than all other weather events combined. These conditions can be distinguished from each other using a remote sensing optical technique we developed. This allows a vehicle’s safety system to react preventively and therefore reduce accidents or mitigate their effects. A reduction in speed from 60 to 40 mph reduces the risk of fatality in frontal impacts from 90% to 15%, while a reduction in speed from 45 to 30 mph reduces the risk of fatality in side impacts from 95% to 25%.

Aircraft icing is a worldwide problem that can occur anytime on aircraft of any size, depending on the flight altitude. For instance, a flight from Brazilian airliner Voepass Linhas Aéreas crashed near São Paulo on August 9, 2024, after the plane’s de-icing systems failed. An Air France flight crashed in the Atlantic Ocean on June 1, 2009, after ice blocked the aircraft airspeed probes. Unfortunately, in both cases, all occupants died.

A new type of aircraft icing detection system (IDS) we developed consists of a microwave resonator unit (MRU) to measure ice accretion onto the aircraft, and an optical icing detection unit (OIDU) to estimate the icing-hazard potential of the atmosphere around the aircraft. Results of the flight tests of the IDS in a jet aircraft with reference scientific measurements indicates that this new system is the only one capable of detecting ice accretion onto the aircraft, and of discriminating between common icing conditions and the more hazardous supercooled large droplets (SLDs) that has caused many aircraft accidents. Indeed, the IDS is the only system capable of directly measuring cloud drop size.

A slightly different version of the optical sensor was developed to monitor the conditions of the road ahead of a vehicle. This road condition monitoring system (RCMS) has been demonstrated to be capable of distinguishing dry, icy, snowy, and wet roads from each other more than 100 ft ahead of the vehicle. This allows the driver or vehicle’s safety system to react preventively and saving lives by reducing accidents or mitigating their effects.

Prototypes of the innovative IDS and RCMS have been used to demonstrate their potential to save lives by detecting hazardous environmental conditions around aircraft or ahead of vehicles. The development of commercial versions of these technologies is being discussed with potential partners.