Although nothing is mind-boggling or mysterious about flying, there is much to learn -- just as there is in learning to drive a car. As you learn to fly step by step, you'll find your training enjoyable and challenging.

Although airplanes have been a part of our society for more than 85 years, most people have only a vague idea of the basic principles of flight. Flight may seem complicated, but in fact it's based on some simple laws of nature.

The principle of lift

When you examine a cross-section of an airplane's wing, or airfoil, you'll notice that the top part is curved and the bottom part is relatively flat. This special shape creates lift, which makes the airplane fly.

As the wing moves forward, the air flowing over the top travels faster than the air flowing beneath, resulting in a lower pressure area above the wing. The relative pressure differential provides the upward force called lift. Lift is basic to flying.

Lift and gravity

In order for an airplane to climb, lift must be greater than gravity, the force that holds objects on the earth.

For an airplane to maintain level flight at a particular altitude, lift and gravity must be the same, or in equilibrium. When gravity is greater than lift, the airplane will descend.

Thrust and drag

As an airplane moves forward, the wing produces lift. The force of forward movement is called thrust, and it's created by the engine-driven propeller or a jet engine.

Like the wing, the propeller is also an airfoil. As it rotates, it creates "lift" in a forward direction that is called thrust. Thrust overcomes drag (resistance of an object toward movement).

When thrust is greater than drag, during takeoff, for instance, the airplane's speed increases. When thrust and drag are equal, the airplane maintains the same speed. Whenever drag is greater than thrust, the plane slows down.

Lift, gravity, thrust, and drag are the four forces acting upon the airplane. You'll learn to understand them thoroughly as you advance in your study of flight.

The parts of an airplane

An airplane, of course, is more than a wing, a propeller, and an engine.

The body of the airplane, which holds the pilot, passengers, and baggage, is called the fuselage.

The tail of the airplane is called the empennage, and it consists of the horizontal and vertical surfaces called stabilizers. They create the stability necessary to use the lift and thrust created by the wing and the engine-driven propeller.

Parts of the wing, horizontal stabilizer, and vertical stabilizer are movable to provide the pilot with the means to control the airplane. These control surfaces are called ailerons on the wings, elevators on the horizontal stabilizer, and rudder on the vertical stabilizer.

You'll become as familiar with the workings of these different parts as you are with the operation of a car.

Control

As the pilot, you control the airplane, and determine how it flies. The different movements of your controls will cause corresponding movements in the airplane. Here are some basic airplane movements.

Pulling the control wheel toward you raises the elevator, which in turn forces the tail down and the nose up. This serves to create more lift than gravity and the airplane will climb. To help produce the extra lift needed in the climb, you usually need additional power from the engine, which you achieve by using the throttle control. Pushing the control wheel away from you lowers the elevator, forcing the tail up and the nose down. This reduces the lift, and gravity makes you descend.

The rudder pedals control the movement of the plane from right to left in much the same way as the rudder of a boat. Pushing the right rudder pedal forces the nose of the airplane to the right, and the left rudder pedal produces the same movement to the left.

Turning the control wheel moves the ailerons in opposite directions, enabling you to raise or lower either the right or left wing which enables the airplane to turn faster than using rudder only.

To change the attitude of the airplane, its relationship to the horizon, you simply use the control surfaces and the power of the airplane. It's an exercise in coordination, much like riding a bicycle. Your flight instructor will discuss with you how these simple movements can be combined to maneuver the airplane.

Pilot licenses (in the United States, airman certificates) are issued by national aviation authorities, and establish that the holder has been trained by a qualified flight instructor and has met a specific set of knowledge and experience requirements. The licensed or certificated pilot can then exercise a specific set of privileges in the nations airspace. Despite attempts to harmonize the requirements between nations, the differences in certification practices and standards from place to place serve to limit full international validity of the national qualifications.

In the U.S., airman certificates are issued by the Federal Aviation Administration (FAA) — and pilots are certificated, not licensed, although the word license (note the spelling) is still commonly used informally. Legally airman certificates can be revoked by administrative action; whereas Licensing requires intervention by the judiciary system. In Canada, licenses are issued by Transport Canada, and in the United Kingdom by the Civil Aviation Authority (CAA).

At all times, an aircraft in flight must be under the authority of an appropriately qualified pilot, the pilot in command, who is responsible for the safe and legal completion of the flight.

General structure of certification

Pilots are qualified to fly at a specific privilege level and in one or more specific categories of aircraft. Examples of privilege levels found in most countries are:

• Student: the pilot can be trained by an instructor for his or her first full certificate and is permitted to fly alone (solo) under specified circumstances.
• Private: the pilot can fly for his or her own pleasure and is not allowed to accept compensation for flying except in some specific circumstances.
• Commercial: the pilot can fly for hire.
• Airline Transport: the pilot can be the captain for a scheduled airline.

The licenses are also further broken down into category, class, and in some cases, rating.

A category is defined as "a broad classification of aircraft", broken down into Airplane, Rotor craft, Glider, and Lighter-Than-Air. A class is defined as "a classification of aircraft within a category having similar operating characteristics", which include single engine, multi-engine, land, water, gyro plane, helicopter, airship, and free balloon. In addition, a type rating is required for aircraft over 12,500 pounds, or aircraft which are turbojet powered. Further endorsements are required for high performance (200 horsepower or greater), complex (retractable landing gear, flaps, and a controllable pitch propeller), or tail wheel equipped aircraft, as well as high altitude operations.

Most Private Pilot certificates are issued as "Private Pilot: Airplane Single Engine Land", which means the pilot may employ his piloting privileges in any single engine, land based airplane he is qualified in. A pilot is only qualified in the category and class of aircraft he takes his check ride in. Therefore, a pilot who takes a Commercial Pilot check ride in a multi-engine, land-based aircraft and passes may only exercise the privileges of a Commercial Pilot in multi-engine, land-based aircraft. That pilot may not exercise the privileges of a Commercial Pilot in single engine or sea-based aircraft without passing the appropriate parts of a check ride in those particular categories of aircraft.

The typical order in which a pilot obtains ratings is: Private Pilot (35-40 hours total time required) Instrument Rating Commercial Pilot (190-250 hours total time required) Airline Transport Pilot

In the course of the Commercial Pilot training, most pilots will also receive their high performance and complex endorsements, as well as get a multi-engine rating before applying for the Airline Transport Pilot license.

Others include

Sport pilot certificate (United States only), used for Light-sport aircraft, a category that was designated in 2004. These aircraft are larger and faster than U.S. ultra lights, and carry more fuel and often one passenger.
The ultralight category of aircraft in the U.S. requires no specific training and no certification.