Green Wings

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Like anyone else I am concerned about the high cost of avgas, so I decided to see how long I could fly on the least amount of gas. I managed to fly almost two hours using only a couple gallons of gas. Even better, the cost of the airplane was only $10 and the total cost for the flight was a miserly $55.

As you may have guessed, I was flying a glider, the original green machine. Gliders, or sailplanes as the higher performance versions are called, are my favorite way to fly. The basics of powered flight are pretty simple. As long as you keep the airplane pointed in the right direction and don't run out of gas you will end up where you want to go. With the modern glass cockpits and handheld GPS navigators, you don't even have to work hard to put together a mental picture of where you are and what is going on around you.

Gliders are a very different story. In training gliders like the Schweitzer 2-33, we are talking about back to basics. There are typically only five instruments: a magnetic compass, an airspeed indicator, an altimeter, a rate of climb indicator, and a short length of yarn taped to the canopy to indicate slips or skids. The controls consist of a stick and two rudder pedals, along with a handle that extends the spoilers and a knob to release the tow rope. An air vent rounds out the cockpit. The more advanced sailplanes add a sophisticated variometer with audio tones indicating whether you are climbing or descending, GPS and even a special soaring computer, but when starting out the very basics are typically all you have to work with.

Because gliders are so simple, they are fairly easy to learn how to fly. You can solo a glider at 14 and get your license at 16. Only 10 flights (two hours) are required for a power pilot to add on a glider rating. But don't let that fool you. There is a lot to learn, and getting a glider rating can improve a pilot's skills when he is flying behind an engine.

While it is possible to use a winch to get into the air, most glider flights start with an aero tow. The glider takes off well before the tow plane. This calls for some very precise flying because if the glider zooms up too high it can tip the tow plane up on its nose, and if it does not stay centered behind the tow plane, it can turn it. So immediately after lifting off the task is to stay directly behind the tow plane only a few feet off the ground as the tow plane continues to accelerate. Once the tow plane lifts off, most glider pilots use a "high tow" position, flying above the wake turbulence behind the tow plane. Visually keeping the tow plane on the horizon will put the glider in the correct position. The glider pilot also learns how to "box the wake," flying around the tow plane's wake and even descending through it.

It is best if the glider is upwind of the airport when it releases from the tow, so the tow pilot will make smooth turns to get in the proper position. An experienced tow pilot will also do his best to get the glider into an area of lift. During these turns the glider pilot is essentially flying formation with the tow plane it is attached to, and the pilot has to smoothly follow the tow plane through any turns. Turns or turbulence or pilot error can lead to a slack tow rope, and the glider pilot learns how to smoothly take up the slack without breaking the rope.

During the tow the glider controls feel stiff and only small control inputs are necessary because the glider is flying faster than its normal soaring speed. After reaching the desired altitude, usually 2,000 to 3,000 feet agl, the glider pilot pulls the release knob and initiates a gentle climbing turn to the right as the tow plane descends to the left. The pilot slows the glider to its minimum sink speed, which is about 40 mph in a 2-33. At this point the budding glider pilot learns (or remembers) how sloppy the controls get at slow airspeeds.

If the pilot is going to make coordinated turns, he also rediscovers his feet. A long wing combined with a relatively small rudder leads to serious adverse yaw. This is where the yarn on the canopy comes in. For the first few flights the yarn is seldom in the middle as the glider yaws with every turn. Gradually the pilot learns to apply the proper amount of rudder pressure to keep the glider in coordinated flight.

To help return to the airport safely, each runway has a key position. The goal is to arrive at the appropriate location at 1,000 feet agl. At that point the airspeed of the glider is increased to pattern speed (55 mph in the 2-33) by lowering the nose, and the pilot flies a typical pattern of downwind, base and final. Since every landing in a glider is a power-off spot landing, the pilot varies the pattern to adjust for the wind, aided by spoilers that increase the rate of descent without affecting the glider's attitude. Some gliders also have flaps.

Any power pilot who has not been convinced that it is necessary to increase airspeed when gliding into a headwind in order to make it to the airport will quickly become a believer in a glider. Because of the slow speed of a glider, if there is any significant wind down the runway the only way to make it back to the airport is to get the nose down and the airspeed up. With only one wheel with no suspension under the glider, along with small outrigger wheels at the ends of the wing, a glider is flown onto the runway and obviously has to be "flown" until it comes to a stop and one wing drops to the ground. Pulling back on the spoiler handle applies the brake.

While the precision necessary on takeoff and the planning necessary to make it back to the airport without an engine are a challenge, the true joy of flying a glider comes during soaring flight. Aside from ridge or wave soaring, most glider pilots stay in the air and even climb by finding and staying in thermals. A thermal is a bubble or column of air that has been heated by the surface to the point that it breaks free and starts to rise. Those annoying bumps that the power pilot tries to avoid are the source of lift that keeps the glider in the air.

Even during the tow the glider pilot will be alert for any lift and note its location. After releasing from the tow, the pilot heads towards an area he thinks might have lift. Carefully flying at minimum sink speed, the pilot maintains a very light touch on the controls. Like a fisherman trying to sense a bite, the pilot watches for any indication of a thermal. Since the glider will rarely hit a thermal in the center, this is usually indicated by one wing rising. It may be a satisfying wallop in the pants, or it may be just a momentary rise of one wing.

Once the pilot senses lift, the challenge is to find the center of the thermal where the maximum lift is. There are quite a few tips to help with this, but the basic idea is to turn towards the thermal and then observe the variations in lift and adjust the bank angle to try to find and stay in the area of maximum lift. This really helps with control at minimum airspeed, as you basically end up doing steep turns just above stall in somewhat turbulent air. As the pilot reaches the top of the thermal the lift will taper off. It is then time to set off in search of another thermal.

A cross-country flight in a glider consists of thermaling at minimum sink speed, then cruising at best glide speed or higher in the desired direction until enough altitude is lost that it is necessary to find another thermal. There are a series of internationally recognized badges to challenge a glider pilot to increase his soaring skills. The Silver Badge requires a 3,281-foot altitude gain, a five-hour flight, and a cross-country flight of at least 31 miles. The goals increase to the Diamond Badge, which requires a 16,404-foot altitude gain, a 186-mile flight over a pre-declared course, and a 310-mile cross-country flight. There are also soaring competitions with pilots in standardized classes of gliders competing against each other. Obviously an intimate knowledge of the weather is critical to successful cross-country flights in a glider, so glider pilots go far beyond the basics to learn how to determine the likelihood of making the desired goal.

It is amazing what an experienced pilot can do in an advanced sailplane. The longest flight so far is over 1,800 miles, the fastest speed over a 100 km course is 155 mph, and the highest altitude achieved is 49,000 feet. The endurance record had reached 22 hours when it was decided to no longer keep those records because pilots attempting to set a new record were falling asleep and crashing!

While the cost of operating a glider is much less than a power airplane, I had an unfair advantage on my flight because I was flying a Civil Air Patrol glider that is available for $10 per flight. A rental glider would have cost me $39 per hour or $78 for the two-hour flight, still a good deal compared to renting a single engine airplane for two hours. There are soaring clubs in many areas that offer significantly reduced costs.

One of the best parts of getting involved in soaring is the camaraderie among glider pilots. Glider operations are often low key affairs that harken back to the early days of aviation. I am now flying out of Turf Soaring School (turfsoaring.com) in Peoria, Arizona, north of Phoenix. It has an open porch with a parrot named Bebop who welcomes visitors with a hearty "hello" and picnic tables under the trees where the entire family can watch the action.

Obviously gliders will never take the place of powered airplanes for practical applications, but if the inflation in the cost of the $100 hamburger is getting you down and you are looking for a new challenge and a way to improve your skills as an aviator, flying a glider is one of the most enjoyable ways to do so. More information is available from the Soaring Society of America at ssa.org.