Cockpit instruments explained simply
The cockpit of an aircraft contains many gauges and instruments. The six most important instruments are often referred to as the "Six Pack." They provide the basic information a pilot needs at all times: speed, altitude, attitude of the aircraft, heading, and rate of climb or descent.
The artificial horizon
The artificial horizon shows the aircraft's orientation in space. It indicates whether the nose is pointing up or down and whether the aircraft is tilted left or right. A small aircraft symbol is located in the center, with a representation of the sky and ground behind it. This instrument is particularly important in bad weather or cloudy conditions when no natural horizon is visible. The artificial horizon is one of the instruments that uses a gyroscope.
The airspeed indicator
The airspeed indicator shows how fast the aircraft is moving through the air. The speed is usually displayed in knots. One knot is equivalent to 1.852 kilometers per hour. The airspeed indicator doesn't measure speed over the ground, but rather speed relative to the surrounding air. It does this using the so-called pitot tube static pressure. At the front of the aircraft is a small tube that measures the air pressure of the slipstream. Together with the normal ambient air pressure, the instrument calculates the airspeed. Many airspeed indicators have colored markings. These indicate important speed ranges, for example, for normal flight, for the use of the landing flaps, or the maximum permissible speed.
The altimeter
The altimeter indicates the aircraft's altitude. Altitude is usually given in feet. 1,000 feet is approximately 305 meters. The altimeter doesn't measure altitude directly, but rather via air pressure. As altitude increases, air pressure decreases. The instrument therefore compares the outside pressure with a preset reference value. This allows the pilot to read the current altitude. Since air pressure changes depending on the weather, the correct air pressure value must be set before takeoff. Otherwise, the altimeter will display an incorrect altitude.
The turning indicator
The turn indicator shows whether the aircraft is turning left or right. Additionally, it allows the pilot to see whether the turn is being flown in a coordinated manner or whether the aircraft is sliding sideways. Beneath the instrument, there is often a small ball inside a curved tube. If the ball stays in the center, the turn was flown cleanly. If it moves to the left or right, the aircraft is not flying perfectly balanced. Pilots often remember the phrase: "Step on the ball" – meaning to apply rudder in the direction of the ball.
The course carousel
The directional gyro indicates the flight direction more accurately than a normal magnetic compass. It also works with a gyroscope and reacts more smoothly and precisely. While the magnetic compass often becomes unstable due to turns or turbulence, the directional gyro remains stable. Therefore, pilots usually rely more on the directional gyro for orientation during flight and regularly compare it with the magnetic compass.
The Variometer
The variometer, also called Vertical Speed Indicator or VSI, shows whether the aircraft is climbing or descending – and how fast. The reading is usually given in feet per minute. If the reading is +500, the aircraft climbs at 500 feet per minute. At -500, it descends at the same rate. The variometer reacts somewhat slower than other instruments because it only registers changes in air pressure over a short period.
The classic cockpit layout
In many smaller aircraft, the six most important instruments are always arranged similarly. In the top row, the airspeed indicator is on the left, the artificial horizon in the middle, and the altimeter on the right. The yaw indicator is usually located on the left, the heading indicator in the middle, and the variometer on the right. This arrangement is often called the "Basic T" because the instruments together form the shape of a T. This allows the pilot to quickly find the correct reading, even under stress.
Modern aircraft cockpits
Modern aircraft often no longer have individual round instruments. Instead, information is displayed on large screens. These systems are called glass cockpits. The most important information remains the same: speed, altitude, attitude, heading, and climb or descent. Even in a glass cockpit, the display usually follows the classic instrument layout.
