Pressure Gauges: In many of the systems associated with the operation of the aircraft and its engines, liquids and gases are used, the pressures of which must be measured and indicated. The gauges and indicating systems fall into two categories: Direct Reading and Remote Indicating. Remote indicating is where a separate sensing element is connected to a pressure source at some remote point.

Air Speed Indicator is the only instrument that uses both Static and Dynamic pressure. It shows Indicated or Calibrated speed, and with a mechanism that compensates for altitude and temperature corrections, it can also show True Air Speed. It has Arcs and Markings for a big variety of speeds like, Vs, Vso, V flaps extend, Vno, Vne.

Altimeter is an instrument used to measure the altitude of an aeroplane above a fixed level. Altitude can be determined based on the measurement of atmospheric pressure. The greater the altitude, the lower the pressure. When a barometer is supplied with a nonlinear calibration so as to indicate altitude, the instrument is a type of altimeter called a pressure altimeter or barometric altimeter.

Vertical Speed Indicator (VSI), also known as a Rate of Climb and Descent Indicator (RCDI), is an instrument which indicates the rate of climb or descent of an aircraft. The VSI uses the aircraft's pitot-static system to determine the vertical speed and depicts the result on a conventional needle and circular scale instrument, or on a ribbon at the side of an Electronic Flight Instrument System EADI.

Artificial horizon (AI), formerly known as the Gyro Horizon or Artificial Horizon, is a flight instrument that informs the pilot of the aircraft orientation relative to Earth's horizon, and gives an immediate indication of the smallest orientation change. The miniature aircraft and horizon bar mimic the relationship of the aircraft relative to the actual horizon. It is a primary instrument for flight in instrument meteorological conditions.

Fuel quantity indication: The fuel level and flow measurement data is typically displayed in the cockpit on a Fuel Quantity Indicator (FQI). The FQI shows the amount of fuel in each tank, as well as the total amount of fuel on board. The FQI also shows the fuel flow rate for each engine. Uses 28VDC.

Magnetic compass: In navigation, an instrument for determining direction on the surface of Earth by means of a magnetic pointer that aligns itself with Earth’s magnetic field. The Magnetic Compass is the oldest and most familiar type of compass and is used in different forms in aircraft, ships, and land vehicles.

Gyros: Gyroscopic flight instruments of some description are used in most general aviation aircraft and in older commercial aircraft. Examples of such instruments include attitude indicators, heading indicators and turn coordinators (turn and slip indicator). The gyroscopes within the instruments are usually electrically or vacuum driven and make use of the basic gyroscopic principles to display the attitude of the aircraft. In more modern installations, mechanical gyroscopes have been replaced by laser gyros.

Oil Pressure measures the pressure in pounds per square inch (psi) of the oil supplied to the engine. Green indicates the normal operating range, while red indicates the minimum and maximum pressures.

Fuel pressure allows you to monitor the fuel pressure while the engine is under a load.

Manifold Pressure measures the Manifold Absolute Pressure, or the absolute pressure of the fuel/air charge inside the intake manifold.

Fuel quantity indicates the amount of fuel measured by a sensing unit in each fuel tank and displayed in pounds or gallons.

Τurn and Bank Coordinator: A Turn Coordinator displays the Rate of Turn as well as roll information and is used to determine the coordination of a turn (e.g., slipping or skidding) and the bank angle required for a specific Rate of Turn (e.g., 2 minutes for 360 degrees). The Turn Indicator is a gyroscopic instrument that works on the principle of precession.

Suction gauge: In some aircraft, all the gyros are vacuum, pressure, or electrically operated. In other aircraft, vacuum or pressure systems provide the power for the heading and attitude indicators, while the electrical system provides the power for the turn coordinator. Most aircraft have at least two sources of power to ensure at least one source of bank information is available if one power source fails. The vacuum or pressure system spins the gyro by drawing a stream of air against the rotor vanes to spin the rotor at high speed, much like the operation of a waterwheel or turbine. The amount of vacuum or pressure required for instrument operation varies, but is usually between 4.5 "Hg and 5.5 "Hg and it is monitored through the Suction gauge.

The instruments which obtain their readings through pressure measurement are oil pressure gauge, fuel pressure gauge, manifold pressure gauge, altimeter, vertical speed indicator, airspeed indicator, suction gauge.