Terrain awareness and warning systems (TAWS) provide acoustic and visual alerts to flight crews when the path of their aircraft is predicted to collide with terrain, water or obstacles. This gives the crew sufficient time to take evasive action.
Airplane collisions with ground, water or obstacles, called “controlled flights into terrain,” often result in fatalities. The new regulations will significantly reduce the risk of such collisions.
In October 2011, Minister Lebel approved the proposed regulations and recommended them to the Treasury Board. The amendments require TAWS to be installed in private turbine-powered and commercial airplanes with six or more passenger seats to prevent controlled flights into terrain.
The new regulations will replace the current regulatory requirement for a ground proximity warning system (GPWS) under section 605.37 of the Canadian Aviation Regulations. In comparison to GPWS, TAWS gives the flight crew much earlier acoustic and visual warnings of a collision, and does so under conditions where GPWS cannot.
The regulatory amendments require TAWS to be installed with an enhanced altitude accuracy function. TAWS requires precise altitude information to work properly in all climates. Without the enhanced altitude accuracy function, TAWS may give altitude readings that are incorrect by up to 500 feet because of factors such as air pressure and frigid temperatures.
Most Canadian operators that fly passenger airplanes internationally have already equipped their fleets with TAWS. It is estimated that the new regulations will save approximately $215 million over a 10-year period by preventing these types of accidents.
July 2012
