A Time of Change in the Surveying Profession
My career as a surveyor has encompassed revolutionary changes in technology. I started with tape and engineer's transit and this has evolved to satellite positioning. Digital data collection and computer processing and drafting have become essential tools of the surveyor. Whereas in 1956 the tape was still the primary tool for distance measurement such as during the Saskatchewan-NWT Boundary Survey , even for the following season of this project perhaps the first electronic distance measurement instrument (EDM) in Canada, an early Geodimeter, was brought out to check and verify the tape measurements we had taken. The geodimeter from Sweden had evolved parallel to the radar based measurement process by Tellurometer from South Africa. The Tellurometer was able to span much longer distances, hundreds of kilometers, in fact, given straight line visibility, and soon became the standard for the longer distances required in geodetic and hydrographic surveying. A novel method to extend geodetic control over large areas became what was called Aerodist, tellurometer signals exchanged between two ground stations and an airplane flying at right angles to the line between them about halfway. The two measured slope distances were reduced to a single distance between the two stations by applying the height of the plane, allowed for the computation of geodetic control by trilateration, rather than triangulation with precise angles and an accurately tape measured baseline as previously used.
I was previleged to work on this type of project, the geodetic survey by trilaterarion of the entire country of Guyana in South America, executed by Terra Surveys of Canada in 1968. Acting as party chief of a remote ground station crew, I was able to experience the outlying areas of this fascinating country.Occupying remote stations with a crew of four, I ws operating one of the two tellurometers at the ends of each line being measured, not even being able to see the airplane which was flying between the two end points of the line, only being in radio contact with it. Long distance station mobilization was achieved by light airplane and direct mobilization to each remote station with two helicopters. Some stations had aluminum towers installed over the station mark in clearings in the tropical rain forest, others were on prominences of the ground with line of sight to an airplane flying anywhere between 100 km and 300 km away.It was an exciting job, dealing with piranhas and poisonous snakes, being out of contact, except by radio, with the outside world for weeks at a time, until new food supplies could be brought out by one of the helicopters. Look at some photos from this experience here
Another interesting experience was my participation and direction of a second-order control survey in Northern Manitoba carried out for the Provincial government in 1977. This was a traversing survey utilising Lambert alumininum towers. The novelty on this job was that the towers were carried in assembled state via helicopter from station to station. Prior to arrival of the tower the sites had to be cleared of forest and undergrowth, and three anchor bolts were installed in a pattern around the tower location. While the copter howered over the station with the tower and anchor cables dangling, the base of the tower was manhandled onto the station marker by several men and the cables were secured to the anchors by others. Once tension had been applied to the cables the helicopter was able to release the tower. Look at some photos here