Since I am presently unable to pratice my craft due to the total absence of money in the equipment development industry, I have been putting some time into volunteering and community work.
There was a small amount of money ‘left over’ from a recent FAA grant and fuel tax funded runway and taxiway improvement project at the small community airport that is in front of my house, office and shop. We asked and received FAA approval to use the left over cash to do a complete survey of the airport, and retained the services of a local registered civil engineer and licensed land surveyor. I volunteered to act as his rodman in order to save money while accomplishing the survey.
I was trained as a civil engineer, but have never worked in the field beyond the college summer jobs I held in the early 1960s. In my very limited experience, a survey like the one we are conducting would be done by a 3 person crew using a transit, rod and chain (a heavy duty specially marked measuring tape). The crew would consist of an instrument man, lead chain man and a stake setter. Surveying our airport property would take at least a week of these three people working 8+ hour days, perhaps more.
After waiting out several passing storms over the last week, we began the survey field work this afternoon, but using year 2000+ technology. Rather than a transit, the survey instrument is a Nikon theodolite. The only other piece of equipment is a rod with a precision prism target on the top and an optical level bubble at the midpoint. No chain is required. The theodolite is fully electronic, only requiring that the operator define the target at each shot. It determines the bearing (azimuth), vertical displacement (height) and slope distance between the instrument and the target on the top of the rod. In operation, this takes only a few seconds for each shot. It takes a lot longer to walk between the points!
The surveyor had previously set several “control points,” where he placed the instrument. Again, these points are arbitrarily chosen based on the ground to be surveyed and to be out of the way of automobile and aircraft traffic. He had placed a surveyor’s nail in the pavement at the control points. The theodolite even aligns itself precisely over the nail, with only a little help from the operator.
My job as rodman was to walk to each desired measurement point, put the rod on the point, get the level bubble in the center of the glass and call “point” on the radio. The surveyor calls back “good” when the theodolite has captured the data. Every point is chosen arbitrarily, based on what we are interested in and what we want to record. No stake setting required.
We worked about 4 hours today and completed well over 65% of the airport. We did have an additional person as safety officer carrying a handheld aircraft frequency transceiver to communicate with any approaching or departing aircraft and to warn me to vacate the runway to allow aircraft to takeoff or land. There was only one aircraft operation all afternoon, typical for our small country airport.
BTW, my friend and neighbor Jim was the safety officer. He spent one career as a U.S. Air Force mechanic on piston, then jet fighter planes. His second career was working for North American Aviation as a field engineer on Air Force fighter jets. His final career was as a ground services manager for the space shuttle. He took early retirement when the Challenger crash caused a hiatus in the shuttle program. Jim is well into his 80s, is a near lifetime pilot, owns two airplanes and flies them both regularly!
Darkness, cold and old age of the volunteers (Jim & myself) stopped our work at about 5:00pm. We expect to be able to complete the survey in about 2 to 3 more hours, but there are a series of storms moving into N. California, so we might not get to it until late next week.
Once all the points are stored, the surveyor will bring a very special precision GPS location device. That device will be used to accurately locate the (previously arbitrarily chosen) control points with an absolute accuracy of approximately 1/16"! The location of the control points is then applied by a computer program to all the points we shot today. Who says technology isn’t neat!!
Some of that data will be put into federal data bases and coordinate systems for future use in developing instrument approaches, etc. Other parts of the survey data will be used in future airport land acquisition, engineering and construction projects. It will also be used in determining appropriate setbacks and checking height restrictions for nearby trees, fences, buildings and other other potential obstructions to safe aircraft operation.
A tiring, but rewarding afternoon spent doing some community good and working with a couple of very good men.
Happy RRing,
Jerry
