This tower is an integral part of Canada's air navigation system. Now, having said that recent technological changes, including the use of GPS for air navigation is quickly advancing and may soon make this tower and many others obsolete; but so far governing agencies still have some concerns in a regulatory environment to assure that the new methods are as safe as the older, proven technology as there is no cast in concrete rules for the newer methods of navigation or protocols that envelope all the currentl requirements and some airport approaches are published by the non-traditional groups that are not the same in regards to minimum altitudes, points of intersection, or have not been proven and approved by the regulating bodies of the countries of the world to ensure safe air navigation. No doubt, as progress is made, these concerns will be addressed on an international basis as has been done in the past.
This particular structure serves as a marker for aircraft to intercept when on approach to Runway 15 at London International Airport so that the aircraft may line up on the approach using instruments and intercept the instrument landing system at a known distance from the airport. It is also a known point used by aircraft that have to do a 'missed approach' when landing on Runway 27 due to the fact that they are at minimum approach altitude approaching the runway and cannot see the runway. In such a situation the aircraft will do a missed approach, make a turn to the right away from Runway 27 and proceed to XU 506 where it will make a turn back towards another aeronatical beacon to the east of the airport if the decision is to make another landing attempt on Runway 27 or possibly other runways which may be more suitable for the aircraft/weather or other items to take into account, including the necessity to travel to an alternate airport.