OCAS system could reduce collisions, power costs, and avian mortality – what’s not to like?

What would you think about a tower safety device that reduces the number of aircraft collisions with towers, is environmentally friendly, and eliminates the need for towers to be continually lit? Too good to be true? Perhaps, but OCAS, Inc. (a company founded by two former military pilots) has petitioned the FCC for approval of just such a system.

Specifically, OCAS has asked the Commission to add a new Subpart T to Part 87 of its rules in order to allow its Obstacle Collision Avoidance System (OCAS ® – hence the company’s acronymic name) to be widely deployed. The technology at work here is similar to air-to-air collision avoidance systems in use for some time now. In fact, the OCAS system itself has been used in a number of locations worldwide, including at some U.S. government (shh!) installations. In light of its successful operations over a period of time – not to mention marketplace demand for an improved obstacle warning system – OCAS is asking the Commission to make the rule changes necessary for the system to be much more widely-used.

The OCAS system consists of three basic components: a low-powered continuous wave radar; an energy supply source to turn on and control the lighting on the structure; and a VHF radio which can transmit simultaneously on virtually all aviation-band frequencies.

The continuously operating radar device is attached on or near the tower (or whatever other air traffic obstacle you want to warn planes away from) and constantly monitors a series of pre-established “warning zones”. If an aircraft enters the first warning zone, the system turns on the tower lights to provide a visual warning to the pilot. If, despite the lights, the apparently errant aircraft advances toward the tower and enters the second warning zone, the VHF radio transmits an audio warning on all aviation transceiver channels alerting the flight crew to take immediate action to avoid a collision. Because of the very modest signal strength of the transmissions – the signal would need extend over only the second warning zone, a relatively modest area – it is very unlikely that any aircraft outside of the danger zone would receive any false alarms.

This system – on paper, at least – screams “user-friendly”. From the operational standpoint, the software governing each individual OCAS® unit can be adjusted to account for unusual terrain at a particular site. Plus, because the tower lights are activated only when an aircraft flies uncomfortably near the tower, use of OCAS® would both save on power costs and extend the life of tower light bulbs. As an added bonus, OCAS could take charge of the required tower monitoring chore and send daily status reports to the tower owner. 

And Mother Nature should be pleased as well:  the fact that the towers no longer would be constantly illuminated should decrease the incidence of fatal bird/tower collisions, since such collisions have been blamed on the disorienting effects on birds of constantly-lit towers.

Overall, with the exploding demand for tall structures – e.g., communications towers, obviously, but also power-generating wind turbines – the OCAS system may be an idea whose time has come. Check back here for updates – we’ll let you know if and when the FCC requests comments on this petition.