My happiest moments are spent in the sky surveying my kingdom. When I was a kid on long flights across the Pacific, I'd look down at sandy atolls and dream of what they must be like. I'd point them out from the jump seat, and my dad would invariably respond with something like, "Yeah, nothing but a bunch of sharks down there." For him, the mystery was gone. He was jaded by spending weeks in a shack in places like Wake Island, playing gin rummy, waiting to be called on a flight when working for a non-sched airline. But, for me, it was exotic, and I dreamed of spotting Amelia's airplane.
Today, I'm still amazed at my bird's-eye view and what I can see from my perch. I can't see as well as a raptor, but I see a lot more than my ground-bound friends, and as always, I wonder why more people aren't "up here" enjoying the same view. People ask me if I get bored flying cross-country, and I think, "How could I possibly be bored when the scenery is always changing?" The landscape fans out into an ever-interesting array of fields and mountains, and section lines so straight that a diagonal curving road looks like a snake in a driveway. Concentric crop circles like alien signs, railroads and long waves of grass, reflections on the water, a river winding into sunset, the Rockies coming into view 60 miles east and, well, you get the drift. I'm always impressed.
But, as much as I can see with a naked eye, there's apparently a lot more that I can't see. It's like sitting on a beach, pondering the meaning of it all, thinking about the universe below the surface—teeming with life but not visible. Like the ocean, what's under the forest and the ground is also hidden, esoteric, a parallel universe, but with new technology called LIDAR, we're starting to be able to see deeper, below the surface, and what has been there all along.
I first read about LIDAR in The New Yorker magazine and have been fascinated with it ever since. LIDAR—which comes from a blending of the words "light" and "radar"—is a remote sensing technology that uses a laser to illuminate a target, enabling analysis of the reflected light and making it possible to map below the surface of the earth for archeology, mapping, geography, seismology, agriculture, forestry and more.
In 2012, LIDAR mapping of remote areas of the La Mosquitia region of Eastern Honduras revealed extensive pre-Columbian era ruins, made visible when a LIDAR-equipped Cessna 337 Skymaster flew over the area. The ruins could be remnants of the legendary La Ciudad Blanca (The White City), also known as the Lost City of the Monkey God. LIDAR-equipped airplanes have been surveying for ancient cultures and have found ruins in Belize and Guatemala. Archaeologist Christopher Fisher, who was part of the Honduras expedition, believes the discovery is momentous and said in a Washington Post article, "We're, in many respects, going to be able to repopulate the Americas. We are going to find all of these places that we previously thought were lightly occupied…And I think we are going to be surprised at the extent of the human occupation of the Americas…And I think that also, theoretically, is going to have a profound influence on archaeology." No doubt. The team hasn't disclosed the exact location of the find due to fears of looting, but has released images that show what appears to be a network of plazas and pyramids, and a planned documentary is in the works. Interestingly, I found that the earliest mention of La Ciudad Blanca appears to have been made by Charles Lindbergh who reported seeing ruins while flying over Honduras in 1927. Lindbergh described it as an "amazing ancient metropolis."
LIDAR uses laser light to measure distances. "Airborne laser scanning" technology, only developed within the past 15 years, is an aircraft-based type of LIDAR that provides extremely accurate and detailed three-dimensional measurements of the ground, vegetation and buildings. A small, lightweight unit, one of LIDAR's first commercial uses was to survey power line corridors for encroaching vegetation, and it has since been used to map landforms and coastal areas. For example, an airplane flying overhead can map landforms with accuracy to within six inches of elevation. In steep forest, accuracy is in the range of one to two feet. LIDAR's speed and accuracy make it possible to map large areas with incredible detail—work that was only done in the past with time-consuming and expensive ground survey crews.
One of the most exciting applications for LIDAR and its sister IFSAR (developed to see through clouds, where LIDAR can't) is the 3-D Elevation Program (3DEP). Operated by the USGS, the goal of the 3DEP program is to map the entire United States. Pilots and sailors love maps. And, we rely on them. It turns out that the charts I learned to fly with in Alaska aren't only inaccurate, but are hopelessly out of date by some 50 years. Who knew? According to Steve Colligan, president of an Anchorage mapping company that specializes in aviation safety, "Mars is better mapped than the state of Alaska." Alaska's maps are so outdated that the 3DEP mapping of the entire U.S. is starting in Alaska.
I kind of like my sectional charts and think of them as my navigating bible. I wonder if they'll change much. The consensus of the mappers is that apparently, they'll change significantly by providing better obstacle height data along with better accuracy of landmarks, which would make a difference in a place like Alaska where pilotage is still a way of life. By the way, the first sectional chart was published in 1930. The navaids have changed, but landmarks probably remain much the same.
There's even a National Center for Airborne Laser Mapping (NCALM) whose mission is to provide airborne light detection and ranging observations to the scientific community. Their latest LIDAR news includes aerial mapping in Guatemala and Honduras, a project helping South Asian countries manage water resources and mapping McMurdo Dry Valleys in Antarctica. The applications seem endless.
Even with our rarified aviator's view of the world, there's so much we don't see. We imagine it, but technology finds it, and aviation is the key to discovering more, LIDAR equipped or not. In Kenya, the anti-poaching patrol aircraft of the Kenya Wildlife Service sometimes fly very low along a river so they can look under trees for signs of poachers. Pilots might not see the wind, but there are cues such as smoke stacks or a band of clear water along a shoreline. We can't see the air, but we can feel it lifting us in the upwind side of a mountain wave. We catch glimpses of water under the trees even if we can't see the stream itself.
The National Air and Space Museum is undergoing a major renovation to its location on the Mall. Some of the airplanes that were hanging are now sitting on the floor. I recently had the opportunity to enter the rarified air of the Spirit of St. Louis and have a look inside the cockpit at the wicker chair Lindbergh sat on when he crossed the pacific. When the airplane is rehung, there will never be an opportunity during my lifetime to be that close or look inside it again.
The things we can't see—figurative and literal. There's so much more. A friend recently told me that in her extensive travels, the most interesting thing she has ever seen was a hole in the ground in the Middle East. Looking into the hole was an archaeological experience, and the sidewalk she was standing on gave her a view of the rooftops of a previous civilization. Look closer, look deeper. Fly higher and further.
|For More Information|
| 3-D Elevation Program
LIDAR Facts From NOAA
National Center For Airborne Laser Mapping