what is the difference between indicated airspeed, true airspeed and ground speed?

Question

really my question should be, what is the difference between true airspeed and ground speed... i know what the difference between indicated airspeed and ground speed is...

Answer 1

Indicated air speed is what you get out of the pitot tube and gets indicated on your gage inside the aircraft. It is in essence what the aircraft "feels"

True airspeed is because at higher altitudes the air is less dense. This means less molecules in the pitot tube and means a lower speed is indicated. TAS uses temperature and air density to come up with the airspeed that the aircraft is actually traveling at. Most of the time a computer does the calculation. for example at 3,000ft your airspeed indicator reads 100knots. This is indicated airspeed. Now at 30,000ft your IAS will also be 100knots but you will be travailing much faster because of air density. Your True airspeed without any wind will be closer to 300 knots.( this means that if you travel at 300 knots at sea level you will be flying at the same speed at 100 knots at 30,000ft.

Ground speed is the airplanes speed over the ground. If there is a headwind the ground speed would be lower than indicated air speed. If a tail wind the Ground speed would be higher than indicated airspeed.

If you don't understand, message me.

Answer 2

Airspeed is the speed of an object through the air whereas ground speed is the speed over the ground. Ground speed is actually just airspeed adjusted for the effects of wind. For instance if your airspeed was 100 knots and you were flying into a 10 knot headwind, your ground speed would be 90 knots, whereas if you were flying with a 10 knot tail wind, your ground speed would be 110 knots.

Now for the difference between TAS and IAS. TAS (True air speed) is the speed of an aircraft relative to the airmass in which it flies. At sea level and at ISA (International Standard Atmosphere) conditions TAS and IAS (Indicated air speed) will be the same. At increasing altitudes, the IAS reduces as the air density is reduced, however TAS will remain the same, therefore TAS is IAS adjusted for changes in air density and altitude.

Answer 3

You left out calibrated airspeed.

Indicated airspeed is read on the AS indicator.

Calibrated airspeed is indicated AS corrected for installation errors.

True airspeed is calibrated AS corrected for the effects of temperature and altitude.

Groundspeed is true AS corrected for the effects of wind velocity and direction.

Answer 4

indicated- read off the instrument, true- corrected for pressure, ground- speed over the ground(e6b flight computer)