How Does an Airplane measure airspeed?

Question

How does an airplane measure airspeed, it doesn't have its wheels on pavement

Answer 1

an airplane is able to measure airspeed and altitude by means of two pitot tubes that connect from the outside of the aircraft to the displays on the pilot's screens in the cocpit. as air rushes past these tubes, it is then computed into a speed and altitude, which are shown on the screens as knots for speed and feet, for altitude.

Answer 2

A small metal tube is on the outside of the aircraft. On airline planes they're on the front under the cockpit windows. On small Cessnas, they're on the bottom of the wing. These tubes are called "pitot tubes". Pitot pronounced pee-to.

        As the airplane flies, air flows through the pitot tubes. The instrument used to measure speed is called the "Airspeed Indictator".  The airspeed indicator is part of the "static system" on the airplane. Somehow the flow of the air is measured and displayed on the instrument. Speed is measured in Knots instead of miles per hour.

         http://en.wikipedia.org/wiki/Pitot-stati...

Answer 3

Usually there is a tube on the nose of the aircraft. it measures the wind speed going into it and thats is usually how they measure airspeed.

Answer 4

air entering the pitot tubes. more complex aircraft i.e airliners have air data computers that take soures like pitot tube, air temp, altitude to compute airspeed to the airspeed indicator, and if all fails switches back to the old fasion day of the pitot tube feeding the airspeed indicator without any computers.

Answer 5

yes

Answer 6

Aircraft measure airspeed by means of comparison of ram air (that is air being forced in at a frontal surface of the aircraft in the slipstream through a pitot tube) versus the static air that is taken into the system via small opening(s) located on the side(s) of the aircraft. Also taken into account when measuring indicated versus true airspeed is outside air temperature and pressure altitude. This is because as aircraft climb higher into thinner, less dense air, the ram air pressure is reduced and therefore must be corrected by means of measuring outside air temp and pressure altitude to yield true airspeed.

Its also good to remember that airspeed is just that; the speed that the aircraft is moving through the air. Groundspeed may be very different. As an example, let's say you are flying at a true airspeed of 150 knots but are flying directly into a 30 knot headwind. Although the speed of the air going past you is 150 knots, your groundspeed will actually be about 120 knots. The reverse can happen with a tailwind.