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First audio visual warning system approved for use in national airspace

By Janice Wood · August 27, 2009 ·

The FAA recently approved the use of Audio Visual Warning Systems (AVWS) in the National Airspace System (NAS). An AVWS is described by the FAA as “a system that activates obstruction lighting and audio signals to alert the pilot of potential collisions with obstacles.”

The Obstacle Collision Avoidance System (OCAS), developed by OCAS Inc., is the first AVWS to be installed, tested, and approved.

An AVWS is designed to significantly reduce the potential for a wire strike or obstacle collision for low-flying aircraft. There are more than 5,000 of these incidents and accidents in the National Transportation Safety Board database.

The OCAS uses a small radar to detect and track an aircraft’s proximity to an obstacle. Two warning zones are defined. The first warning is the activation of medium intensity strobe lights to allow the pilots to visually identify the obstacle. If the pilot does not take action and the aircraft enters the second warning zone, a VHF broadcast is transmitted to the pilot’s radio. The message includes warning tones and a description, such as “POWER LINES…POWER LINES.” The audio warning is the most powerful aspect of the OCAS solution as it provides a warning in any type of visibility or weather conditions, according to company officials.

No additional equipment is required on the aircraft, making the solution available to almost all aircraft.

For more information: OCASInc.com

About Janice Wood

Janice Wood is editor of General Aviation News.

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