ground speed

Meaning

This term refers to the horizontal speed of an aircraft relative to the Earth's surface. Unlike airspeed, which is how fast the plane moves through the air, ground speed tells you how quickly you are actually traveling over the ground, often affected by tailwinds or headwinds.

Examples

• Thanks to a strong tailwind, our ground speed reached nearly 600 miles per hour.

  Thanks to a strong tailwind, our ground speed reached nearly 600 miles per hour.

• The pilot explained that a headwind was reducing our ground speed.

  The pilot explained that a headwind was reducing our ground speed.

• Even though our airspeed was high, our ground speed was much slower due to the wind.

  Even though our airspeed was high, our ground speed was much slower due to the wind.

• The monitor in front of me displays the estimated arrival time and current ground speed.

  The monitor in front of me displays the estimated arrival time and current ground speed.

• We are making good time because our ground speed is higher than average today.

  We are making good time because our ground speed is higher than average today.

Common Mistakes

• ✗ The plane has a very fast land speed.

  ✓ The plane has a very high ground speed.

  'Land speed' is used for land vehicles (like cars setting records on salt flats); 'ground speed' is the correct aviation term.

• ✗ Our ground speed was slow because of air resistance.

  ✓ Our ground speed was slow because of a strong headwind.

  While air resistance exists, in aviation discussions, headwinds or tailwinds are the specific causes mentioned for changes in ground speed.

Related Expressions

Practice

• A strong tailwind can significantly increase a plane's ___.

  💡 The speed of the aircraft relative to the ground.

  Show answer

  ground speed

• According to the flight tracker, our ___ is currently 550 mph.

  💡 How fast we are moving over the Earth.

  Show answer

  ground speed