Flying the Range
Even where there is too little solar energy to produce powerful thermals, there’s another atmospheric engine that can be harnessed to power a glider: wind.
When wind blows against slopes of hills or a range of mountains, it is deflected upward. Glider pilots long ago learned exactly where the best lift is in this upward rush of air. (IT+)Range currents(IT) supply some of the most reliable lift a glider pilot could hope for, and experienced pilots can use a combination of cloud streets and range lift to make long cross-country flights that last hours and cover hundreds of miles—all without a drop of gasoline!
Landing the Glider
bke cacti end old prospectors, glider pilob thrive in the heat One of the hotbeds of gliding is the Mojave Desert, where I got my first taste of the sport. Pear – blossom is one of the sun-baked towns where thousands of glider pilob ride summertime thermals for hours at a time. In the morning, as the sun starb baking the desert, the drone of tow planes begins, and it doesn’t end until nearly sundown. Throughout the day, the sky is thick with gliders.
Glider pilots approach the airport for landing at about 1,000 feet above the ground, at a 45-degree angle to the runway they have decided to land on or that other gliders are using. The runway in use will generally be the one that points into the wind, giving planes that are landing and taking off the advantage of a headwind.
By the time he has approached within 1/4 mile or so of the runway, the glider pilot turns to parallel the runway, but flies downwind, that is on the ”downwind“ traffic pattern leg. The downwind is entered at roughly 600 to 700 feet above the ground.
With the runway still parallel to him, say to his left, the pilot flies downwind until the point on the runway where he intends to land is slightly behind him. That’s when he begins a 90-degree turn toward the runway (to the left). Once the turn is complete, altitude should be about 500 feet from the ground, and the landing point should be ahead of the pilot and to his left.
When he approaches the imaginary extended line of the runway, the pilot begins a 90-degree turn onto the final approach leg. Once the turn onto final approach is complete, the glider should be at an altitude of200 to 300 feet and descending exactly in line with the center of the runway.
As he descends, the pilot uses a combination of elevator control and spoilers to help him remain pointed directly at his intended landing spot. If he appears to be falling short of his aim point, he closes the spoiler and uses the best airspeed to add distance to his glide. If he’s gliding too long, he will use spoilers and perhaps a maneuver called a slip that increases drag by flying the glider slightly sideways to the wind.
When he’s about 10 feet off the ground, the pilot uses the elevator controls to raise the nose to a level attitude in preparation for landing. The plane will glide a short distance beyond the aim point the pilot used during his approach, which the pilot has already accounted for in selecting his approach.
By the time the gentle level-off maneuver, or flare, is complete, the glider will be a couple of feet off the ground, and the pilot will use the spoilers to help bring the glider gently to the ground in a smooth landing.
The words "gliding" and "soaring" are sometimes used interchangeably, but there is a subtle distinction. Gliding is creating lift by trading altitude for speed, and doesn’t necessarily require lifting forces such as thermals or range lift Soaring means staying aloft without losing altitude, and requires some sort of atmospheric boost. A flight can start in a glide, and quickly turn to soaring when the pilot finds a patch of lift
Some glider pilots prefer an even simpler slip indicator—a short piece of string or yarn taped to the outside of the windshield.
If the glider is slipping sideways through the air, the piece of string will be blown sideways in line with the wind, and the pilot will quickly notice that he needs to better coordinate his use of rudder and aileron control to correct it
A glider is at home almost any place where the sun shines and the wind blows, but some regions offer better gliding conditions than others. Desert regions heat quickly with the morning sun and quickly generate high-energy thermals that give gliders a powerful boost.
A prominent mountain ridge in the presence of a steady wind becomes an updraft generator of unequaled power. Combine the desert climate with the topology of the desert Southwest, and you have all the best ingredients for good gliding.
Of course, gliding is popular in every region of the country and around the world, even in many northern latitudes. In the absence of supercharged thermals and ridge currents, glider pilots learn to make the best of the wind and sunshine they have.