Obstacle Collision Avoidance System
Encyclopedia
The Obstacle Collision Avoidance System (OCAS) is designed to alert pilots if their aircraft is in immediate danger of flying into an obstacle. OCAS uses a low power ground based radar to provide detection and tracking of an aircraft's proximity to an obstacle such as a power line
crossing, telecom tower or wind turbine
s. This capability allows the visual warning lights to remain passive until an aircraft is detected and known to be tracking on an unsafe heading. This leaves the nighttime sky free of unnecessary light pollution
thus decreasing public annoyance issues while improving the environmental habitat.
OCAS is currently the only FAA approved Audio Visual Warning System (AVWS)
approved in the National Airspace. OCAS is also the only AVWS approved by the International Dark Sky Association.
OCAS is operational in the US, Canada, Norway and Germany.
, heading and altitude of approaching aircraft and determines whether it will adequately clear the obstacle. A configurable set of rules is applied to define and determine when to warn the aircraft, by which warning devise and signal depending on the calculated time to impact with the obstacle.
Initial Warning - Medium Intensity Lighting: Once the initial threshold is met, the visual warning is activated. This capability allows the lighting system to remain passive (in the off position) the vast majority of the time thus preserving the dark sky environment while adhering to strict safety standards
set out by the FAA.
Secondary Warning - Audio Broadcast: If the initial warning does not result in the pilot altering the flight path, a programmable VHF radio
broadcasts an additional obstruction warning directly to the cockpit. The VHF warning frequencies are adjusted based on local requirements.
With both visual and audio warning capabilities, the OCAS system provides continuous protection 24 hours a day 7 days a week regardless of local visual conditions and without specialized equipment requirements for the general aviation
community.
Electric power transmission
Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...
crossing, telecom tower or wind turbine
Wind turbine
A wind turbine is a device that converts kinetic energy from the wind into mechanical energy. If the mechanical energy is used to produce electricity, the device may be called a wind generator or wind charger. If the mechanical energy is used to drive machinery, such as for grinding grain or...
s. This capability allows the visual warning lights to remain passive until an aircraft is detected and known to be tracking on an unsafe heading. This leaves the nighttime sky free of unnecessary light pollution
Light pollution
Light pollution, also known as photopollution or luminous pollution, is excessive or obtrusive artificial light.The International Dark-Sky Association defines light pollution as:...
thus decreasing public annoyance issues while improving the environmental habitat.
OCAS is currently the only FAA approved Audio Visual Warning System (AVWS)
Audio Visual Warning System
Audio Visual Warning System is an all-weather, day and night, low-voltage, Radar-based obstacle avoidance system that utilizes current obstruction lighting products and does not require additional equipment in an aircraft. AVWS activates obstruction lighting and audio signals to alert pilot’s of...
approved in the National Airspace. OCAS is also the only AVWS approved by the International Dark Sky Association.
OCAS is operational in the US, Canada, Norway and Germany.
Overview
Radar Coverage: The OCAS system is designed to protect obstacles that are vulnerable to low flying aircraft. OCAS detects the ground speedGround speed
Ground speed is the speed of an aircraft relative to the ground. Information displayed to passengers through the entertainment system often gives the aircraft groundspeed rather than airspeed....
, heading and altitude of approaching aircraft and determines whether it will adequately clear the obstacle. A configurable set of rules is applied to define and determine when to warn the aircraft, by which warning devise and signal depending on the calculated time to impact with the obstacle.
Initial Warning - Medium Intensity Lighting: Once the initial threshold is met, the visual warning is activated. This capability allows the lighting system to remain passive (in the off position) the vast majority of the time thus preserving the dark sky environment while adhering to strict safety standards
Safety standards
Safety standards are standards designed to ensure the safety of products, activities or processes, etc. They may be advisory or compulsory and are normally laid down by an advisory or regulatory body that may be either voluntary or statutory...
set out by the FAA.
Secondary Warning - Audio Broadcast: If the initial warning does not result in the pilot altering the flight path, a programmable VHF radio
VHF radio
VHF radio refers to several communications services in the VHF frequency range, including:* Airband aircraft radio* Amateur radio in the 6, 2 and 1-1/4 meter bands* FM radio broadcasts* Marine VHF radio...
broadcasts an additional obstruction warning directly to the cockpit. The VHF warning frequencies are adjusted based on local requirements.
With both visual and audio warning capabilities, the OCAS system provides continuous protection 24 hours a day 7 days a week regardless of local visual conditions and without specialized equipment requirements for the general aviation
General aviation
General aviation is one of the two categories of civil aviation. It refers to all flights other than military and scheduled airline and regular cargo flights, both private and commercial. General aviation flights range from gliders and powered parachutes to large, non-scheduled cargo jet flights...
community.