Getting From Here to There
By Tom Benenson
February 2009
 One way that some instructors whet the appetite of prospective flight students is to take them on a short cross-country flight for a "hamburger" during the introductory flight. It usually works pretty well. The budding aviator returns from the flight brimming with excitement and anxious to share the experience with ground-bound friends and family.
After that introductory flight, the hooked student is typically restricted to the airport traffic pattern and a local practice area designated for airwork. The frustration of not being able to make consistently smooth landings blurs the fond memory of actually going somewhere.
But eventually the student is kicked out of the local nest and begins putting into practice the navigation skills learned for the knowledge exam. Without electronic aids (VOR, ADF or GPS) there are two basic ways of navigating in VFR conditions: dead reckoning and pilotage. (Celestial navigation is a third way but shooting a sighting with a sextant from a general aviation cockpit is difficult.)
There's an ongoing argument whether the proper spelling is "dead" or "ded" reckoning. (The "ded" proponents argue it's for "deduced," while the "dead" group thinks the reference is from a naval practice of throwing a buoyant object overboard to determine the ship's speed relative to the object, which was assumed to be "dead" in the water.)
To navigate by dead reckoning you start with a fixed point (your departure airport, for example) and using your heading, groundspeed (corrected for the wind direction and speed) and the elapsed time calculate your position. If you're over a sparsely settled area or over water where there are no visual checkpoints, dead reckoning is the best you can do. On a pre-GPS flight in a Piper Chieftain with Russ Hancock, chief test pilot with Colemill Enterprises, from Cozumel, Mexico, to New Orleans, an over-water distance of 753 nm, dead reckoning brought us within a couple miles of our calculated landfall on the Louisiana coast. I was impressed at how well dead reckoning worked.
Pilotage, the other VFR navigation method (that uses elements of dead reckoning), is done by marking a course line on a chart (typically a sectional) and selecting easily identified visual checkpoints on the ground along the course and noting the distance between them. The rule is that everything that appears on the chart is on the ground, but not everything on the ground is on the chart. Pilots quickly learn what makes a good checkpoint and what doesn't. Good checkpoints include: drive-in movie theaters with their large reflective screens; lakes with dams; highway intersections; track ovals; fuel farms; grain elevators; small towns and airports. It's also helpful to pick checkpoints that are half a mile or a mile off to the left side of the course line, which makes it easier to more accurately time how long it takes to go between the checkpoints. With the time and distance between points, the groundspeed can be calculated to confirm that there are sufficient fuel reserves. Pilots soon learn that if they draw their course line from the center of the departure airport but then don't turn to their on-course heading until they've climbed out several miles from the airport, they're already off course. At an uncontrolled field, circling back over the airport well above the traffic pattern altitude and waiting to start the timing to the first checkpoint will at least get them started on the right course.
For decades pilots navigating by pilotage have been aided by "air markings," a tradition of visually marking navigation details on buildings and airports that started in 1934 and continues today. According to an article by Ellen Nobles-Harris that appeared in the 99 News magazine, Phoebe F. Omlie, who had been appointed Special Assistant for Air Intelligence of the National Advisory Committee for Aeronautics (NACA, which eventually became NASA) in 1933, convinced the chief of the Airport Marking and Mapping Section of the Bureau of Air Commerce to support an effort to get each state to identify its towns from the air.
Under the marking program, the states were divided into sections of 20 square miles and a marker was painted on the roof of a prominent building with the name of the nearest town at each 15-mile interval.
By 1936, with the approval for 16,000 markings, Omlie enlisted Louise Thaden, Helen Richey, Blanche Noyes, Nancy Harkness and Helen McCloskey, five of the most prominent women pilots, to act as field representatives for the marking program. Adopted by the Ninety-Nines, the National Air Marking Program was the first U.S. government program initiated, planned and directed by a woman with an all-women staff.
After Pearl Harbor was attacked, there was a concern that the markings, particularly on the east and west coasts, would aid enemy pilots in locating potential targets. As a result, Blanche Noyes, a charter member of the Ninety-Nines (and eventually its president), and her team members who had created a number of markings went back and blacked them out. Following the war, Noyes, in charge of the air marking division of the Civil Aeronautics Administration, headed up the effort to replace the markings that had been covered over and to add more.
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