The Art of the Chart
Somewhere in those symbols, lines, and colors is all the information you need to fly from here to there.
- By Stephan Wilkinson
- Air & Space magazine, November 1999
(Page 4 of 5)
The ultimate proof is "flight editing." NOAA has a small fleet of twin-engine airplanes--a Shrike Commander, Turbo Commander, and Citation business jet--that fly back and forth, over the ground covered by sectionals, like lawnmowers cutting row after row of grass. The in-house joke is that the pilots are simply scouting for nice places to retire to, but in fact they're checking virtually every item on the busier sectionals. They come back from their mind-numbing missions with notes that eventually are scribed onto the margins of the sectional under revision: "add new tower," "dragstrip still good landmark," "airport north of road," and, as the last of the drive-ins crumble, the frequent "delete outdoor theater."
"I get upset when pilots tell me that they can use an outdated chart for several years," Ronald Bolton says. "We can have 800 changes on a single sectional in one six-month cycle." Still, many pilots resist spending $7.25 per chart twice a year. Which in my case, as a pilot who ranges the occasional thousand miles from home base, means a not--unreasonable collection of 10 sectionals for compete coverage: $145 a year. Dare I upset Bolton? I break down and buy a new set of sectionals only when my prime chart--the New York sectional--wears out from constant use. (But if an FAA inspector ramp-checks my airplane and finds out-of-date charts, I could get the aeronautical equivalent of a ticket. And were I to have an accident, particularly as a result of getting lost, my negligence could be used against me in an FAA enforcement action.)
The Office of Aeronautical Charting and Cartography is on the cusp of change--some of it good, some of it the subject of much contention. For one thing, the Department of Commerce is trying to kick them out. "Commerce says we no longer fit in NOAA, which is primarily an environmental organization," says director Terry Laydon. "The aeronautical charting business started with charts intended to promote interstate aeronautical commerce, which is why I keep saying we belong in the Department of Commerce." Commerce, however, wants the AC&C shifted to the Department of Transportation, where it probably would be placed under the FAA. "We're concerned about that," says Laydon, "because it isn't clear that the FAA will support the non--aeronautical part of our activities, such as printing and distributing nautical and military charts." Laydon sees obvious efficiencies in the consolidation of such production.
If they do go to the DOT, the Aeronautical Charting and Cartography Division will be renamed Transnav--short for Transportation Navigation Services. But this is the least of Laydon's concerns. "We don't have a lot of name recognition anyway," he says. "Our charts are known as 'NOS charts' [National Ocean Survey] or 'Nozz charts.' Nobody calls them AC&C charts."
The positive changes, however, are the AC&C's increasing reliance upon computerization and automation, the goal being the eventual disappearance of the cartographer's traditional tools and techniques. "It's a dying art," says printing specialist Nick Alsop as he demonstrates how corrections compiled from flight editing and other sources are hand--engraved onto huge plastic sheets. "We'll probably see all of our tools in the Smithsonian someday."
At one end of the spectrum are Alsop and senior cartographer Ray Harris, who uses nothing more than a Koh-i-Noor lead pencil, an eraser, and an X--Acto knife to endlessly, laboriously draw the properly shadowed lumpiness of thousands upon thousands of square miles of mountainous terrain all over the United States. Harris uses as his guide an underlay of U.S. Geological Survey topographic contour lines and an understanding of how the land will thus fall, fold, and furrow.
At the other extreme is young cartographer Rick Luzier, who toils at a computer workstation "drawing" a map with a keyboard and mouse--at the time I visited him he was working on a new, almost totally automated terminal area chart. (A TAC is an adjunct to a sectional that shows in large scale a single particularly busy city--Cincinnati, in this case--that has complex air carrier traffic and numerous altitude and airspace restrictions for light aircraft.)
But Luzier's work shows why human input is still important. He calls up from a computer database the chart layer that depicts man-made obstructions. They are magically placed on the electronic map more precisely than any cartographer could, but some so exactly that their symbols obscure more important information, and so profusely that Cincinnati becomes a blur of black. The computer is undiscriminating and, as requested, obediently flags every building over 200 feet high, but only a few of the skyscrapers need representation. "Most of the things we do manually can be automated if we have the equipment," Alsop explains, "but there's no way to put that much symbology on a single sheet without human judgment coming into play to decide what to print and where to put it."