Laser sensor for safer planes

UNSW Canberra engineers say a low-cost laser sensor which is invulnerable to icing could quickly and accurately measure the velocity of commercial passenger jets.

Current velocity sensors (Pitot tubes) is are susceptible to icing in bad weather, which prevents accurate airspeed measurements. They are considered possible failure points for a number of fatal aircraft accidents.

The UNSW technology is based on laser light, meaning there are no physical components in the airflow. Instead they are located inside the aircraft where the temperature can be controlled.

The laser sensor is considered a reliable backup when Pitot tubes fail. Current backups include GPS, which tend to be less operational during storm conditions (when Pitot tubes are most susceptible to failure).

While the laser sensor is not designed to replace the Pitot tubes entirely, the researchers say it can be used as a low-cost measure to augment the tubes, which will give flight staff more confidence in their readings and help guard against fatal crashes.

The sensor employs the same technology used in laser computer mice, and measures velocity by using the Doppler shift of the light absorbed by oxygen molecules.