Aircraft Owners and Pilots Association Protecting Your Freedom to Fly

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Sun, Shadows, And Section Lines

Not long ago the aeroplane reached astounding heights of a few hundred feet. World War I accelerated the airplane's development so that dastardly pilots and aircrew could drop hand-held bombs and fire guns from open-cockpit machines. The post-war aircraft surplus led to the first commercial use of privately owned aircraft. Although mailbags and precious cargo replaced their weapons of destruction, former military pilots still flew into adversity on every mission, with oil in their faces and scarves around their necks.

While computer technology has virtually changed the world, it cannot compare with how the airplane shrank the world. Who could have imagined that in less than six decades, the Wright brothers' fragile biplane would evolve into supersonic monoplanes? Who could have predicted that propeller-driven aircraft would yield to jumbo jets with wingspans exceeding the length of the Wright Flyer's first flight - and with landing speeds topping most biplanes' redlines? Capt. Elrey B. Jeppesen never imagined that his personal mail-run aeronautical charts would lead to a business that would guide fleets of airliners across the Atlantic. Today, autopilots routinely land jetliners hands-off in near-zero visibility at airfields thousands of miles away. While self-contained inertial navigation systems are still in use, the satellite-based global positioning system (GPS) has set a new standard in precision navigation.

But not everyone shares our appreciation for the advances in technology or our enthusiasm for flying. While some airports are being plowed under for urban expansion, remaining airfields in densely populated areas often fall under the Class B airspace umbrella. Unlike the student pilots of yesteryear, today's students have more to learn - and they still have a limited budget. As a result, there has been a necessary shift from teaching stick-and-rudder skills to understanding technology and communications. The end result may mean that pilot judgment is taking a back seat to air traffic controllers' telling us where to go and how high to fly.

This shift in emphasis on GPS and other electronic devices has nearly made pilotage a lost art. While GPS simplified navigation and is a superb tool, what happens when it fails? If you weren't following checkpoints along your straight-line route, how long will it take to tune a VOR station and orient yourself? Did your straight-line course give you a safe route, or did it take you over mountainous terrain or large bodies of water? While technology is a great visual aid, it will never replace pilot judgment.

The art of navigation dates back to the sailing ships, when the sun's position determined longitude. The modern clock is an outgrowth of the navigator's need to know time to determine position. Similarly, airborne navigators relied on the sun to guide them over water. Although the sextant is past its prime, the sun and section lines are still a viable means of navigating for those willing to look outside.

When this country was founded, land was sectioned into townships consisting of 36 square-mile plots, according to the Bureau of Land Management. Surveyors used Polaris - the North Star - to orient these sections lines to true North. Lines not oriented to true North are caused by surveyor error. In spite of minor variations in magnetic orientation or plot subdividing, section lines still provide excellent orientation. The nation's heartland not only provides a tapestry of color, but its endless section lines, a sunny day, and an aeronautical chart are all that a seasoned pilot needs to navigate.

"But I'm learning to fly so I can be an airline pilot," you say. "I've never had a problem with my GPS. This pilotage stuff is ancient history. I'm not going to fly an open cockpit biplane on a mail run. Why do I need to know this?" All true statements. In fact, if all goes well, pilotage is a moot point. After all, GPS has proven very reliable, can depict warning areas and Class B airspace, predict arrival times, present ground speed and fuel consumption - and maybe even fly the airplane for you. With push-button airplanes performing autoland approaches, perhaps we don't need to learn the basics anymore.

Of course, pilotage might have helped the Boeing 757 crew that lost their gyros and crashed into the ocean shortly after takeoff in South America because they didn't know where they were. Had they transitioned to primary instruments, climbed to VFR on top, considered the sun, and applied a simple time-distance problem, the outcome may have been different. The fact remains that as long as humans inhabit the Earth, the sun and moon will be there to help us, which is why the basics should never be ignored.

Here are two examples that further illustrate where knowing the basics would have paid off: A Navy pilot took off on an early morning flight from San Diego and was working in a warning area over the Pacific Ocean when his heading indicator failed. When he took off, the sun was behind his left shoulder. When he was trying to head back to San Diego, the sun was slightly higher, but still over his left shoulder. What's wrong with this picture? He never considered the sun or the magnetic compass and was heading out to sea, all the time believing that he was returning to the base. He would have run out of fuel and lost the airplane had he not received help from another pilot. By the way, this pilot is now a captain for a major airline.

In another scenario, I was giving an instrument proficiency check in a high-performance single. The plane's instrument panel was decked out with every imaginable toy. We accomplished everything we intended, so we decided to fly VFR to an airport 35 miles away for a couple of landings. While climbing out from the busy tower-controlled airport, on a clear day with airplanes darting around us, the pilot kept fiddling with his GPS rather than looking outside. To comply with noise abatement procedures (it gets noisy if you have a midair), I turned the GPS off, pointed out the traffic, and reminded him that if my memory served me correctly, the airport we wanted was located next to the knoll at our 12 o'clock position. Somehow we managed to find it without using the GPS.

The real danger in technology is pilot complacency. This is particularly true in modern aircraft since the pilots are removed from not only flying the aircraft, but system management as well. Such is the case in airline flying. If the aircraft is navigating by INS or GPS on autopilot, you may as well ask the flight attendant where you are. The pilots can find out, but it may take a couple of minutes. Experience has shown that modern pilots are better at programming computers than flying airplanes, which is why most airlines require their pilots to use the autopilot as much as possible. At this rate, children who practice flying computer games at home will make better pilots - at least until something goes wrong. Piloting is still about judgment, so it's essential that we understand the basics of navigation and pilotage, regardless of how sophisticated our equipment may be.

The sun does more than aid navigation. It also casts shadows - shadows that offer telltale signs of whether your flight conditions are improving or deteriorating. Too many pilots fly into deteriorating weather on a wing and a prayer, hoping that things will improve. When this happens they are usually below radar coverage, not in radio contact, and unable to receive weather updates along the way. Too often these scud-runners are trying to get to an airfield before it's socked in. I've been there.

So here are some simple rules for analyzing shadows. First, consider the time of day. Stratus clouds generally break up as the day progresses and close up as evening approaches. This is particularly true in coastal areas affected by marine layers. Cumulous clouds do just the opposite, developing during the heat of day and dissipating in late afternoon. A convective thunderstorm not associated with a weather front can complete its life cycle in as little as 90 minutes. Knowing this, one can look along the route to see what the shadows are doing. If the clouds are breaking up, there will be definite shadows ahead. If it's clearing, a solid band of light will appear down the road. A lack of sun rays or shadows indicates a solid overcast. The darkest areas may indicate rain. If the weather is questionable and you can't get a weather update, land at the nearest suitable airfield and check the conditions. Wait it out if you need to.

Knowledge is the best tool for keeping a pilot out of trouble. Learning never stops. As you progress through your flight training, don't forget about the basics.

Mark W. Danielson is a retired Navy pilot who currently flies for Federal Express. He has been a CFI for 24 years and has flown more than 8,500 hours.

By Mark Danielson

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