Government of Canada navigation bar

Symbol of the Government of Canada

Primary site navigation bar

Breadcrumb

  1. Home
  2. Organization
  3. Organizational Chart
  4. Safety & Security Group
  5. Civil Aviation
  6. Aviation Safety
  7. Terrain Awareness and Warning Systems - Regulations Published in Canada Gazette Part 2

Terrain Awareness and Warning Systems - Regulations Published in Canada Gazette Part 2

On 04 July, 2012, Transport Canada announced new regulations to enhance the safety of Canadian aviation. The regulations require the installation and operation of Terrain Awareness and Warning Systems (TAWS) in private turbine-powered and commercial airplanes configured with six or more passenger seats (for specific applicability please refer to table below).

The regulatory amendments introduce requirements for the installation of TAWS equipped with an Enhanced Altitude Accuracy (EAA) function. Most current TAWS equipment includes this function; however, operators who have previously installed older TAWS models may not have equipment with this functionality.

Operators have two years from the date the regulations came into force to equip their airplanes with TAWS and five years to equip with EAA.

Benefits

TAWS provide audio and visual alerts to flight crews when the path of the aircraft is expected to collide with terrain, water or obstacles allowing the flight crew sufficient time to take evasive action.

Inadvertent airplane collisions with terrain, water or obstacles, termed Controlled Flight into Terrain (CFIT), often occur when visibility is low or during adverse weather, leaving pilots unaware of the aircraft's proximity to terrain until it is too late. The benefit is even greater for small airplanes, which venture further into remote wilderness or into mountainous terrain. The regulations significantly increase the safety of these operations.

The EAA function

TAWS require precise altitude information to function correctly. It is estimated that a TAWS without an EAA can give altitude readings that are incorrect by up to 500 feet due to such conditions as air pressure and frigid temperatures. Without the enhanced altitude accuracy provision, a TAWS may, under the conditions described above, fail to provide alerts to avoid a CFIT event.

TAWS vs current regulatory requirements

The regulations for TAWS supersede the regulatory requirement for a Ground Proximity Warning System (GPWS) under the current Section 605.37 of the Canadian Aviation Regulations. In comparison to a GPWS, a TAWS provides the flight crew with much earlier aural and visual warnings of an impending collision and provides these warnings under conditions GPWS cannot. For example, GPWS do not have an ability to look ahead of the aircraft to evaluate the potential danger of oncoming terrain or other obstacles. TAWS have a forward-looking terrain display, based on real-time comparison of an aircraft's location coordinates with stored terrain data.

International Compliance

The regulations meet the International Civil Aviation Organization (ICAO) standards and bring Canadian regulations closer to those of other aviation authorities, including those in the US and the EU. In addition, the Transportation Safety Board of Canada recommends the use of TAWS equipment.

The majority of Canadian operators that fly passenger airplanes internationally have already equipped their fleet with TAWS.

Regulatory Requirements for the installation and operation of TAWS

CAR Subparts Regulatory Requirements
Subpart 605

Private turbine-powered aeroplanes and commercial aeroplanes configured with six or more seats, excluding pilot seats, except when operated DAY Visual Flight Rules, would be required to be equipped with Class B TAWS with EAA functionality.

Subpart 703

Aeroplanes configured with six or more seats, excluding pilot seats, except when operated DAY Visual Flight Rules, would be required to be equipped with Class B TAWS with EAA functionality.

Subpart 704

Aeroplanes configured with six to nine passenger seats, except when operated DAY Visual Flight Rules, would be required to be equipped with Class B TAWS with EAA functionality.

Aeroplanes configured with ten or more passenger seats, exclusive of pilot seats, except when operated DAY Visual Flight Rules, would be required to be equipped with Class A TAWS with EAA functionality, a terrain awareness and situational display.

Subpart 705

Aeroplanes would be required to be equipped with Class A TAWS with EAA functionality, a terrain awareness and situational display.

For further information, please contact:

Civil Aviation Communication Centre
1-800-305-2059
Services@tc.gc.ca

Date modified:
2012-10-23

Footer