How Fast Can a Swift Fly? Fastest Birds in Level Flight

How was the swift’s speed measured?

Bird speeds are hard to measure. A bird can be timed easily over a short distance only if you know exactly where it is in three dimensions, and wind can make a bird seem much faster or slower than it really is. Many old speed records came from timing birds next to cars or aircraft, and most are unreliable.

In 2010, a team from Lund University in Sweden measured the flight speeds of common swifts near their breeding colonies with precise tracking methods. During screaming parties, when groups of swifts race around buildings at high speed, the fastest bird reached 31.1 m per second, which is about 111.6 km/h (69.3 mph). The researchers corrected for wind, so this is the speed of the bird through the air, not just its speed over the ground.

The study also showed that swifts fly much more slowly during normal activities such as feeding or their evening climbs. For most of the day, a swift moves at well under half of its top speed, because fast flight burns a lot of energy.

Airspeed and ground speed: why it matters

Scientists separate two kinds of speed:

• Airspeed is how fast the bird moves through the air around it. This shows what its wings and muscles can really do.
• Ground speed is how fast the bird moves over the land below. A tailwind adds to it and a headwind takes away from it.

A swift flying at 40 km/h (25 mph) with a 40 km/h tailwind covers the ground at 80 km/h (50 mph), even though it is not working any harder. Migrating birds often wait for favorable winds for exactly this reason. Many claims of very fast birds turn out to be ground speeds boosted by strong winds, which is why the corrected swift measurement is valuable.

Why are swifts so fast?

Swifts are built for flying. Several features make high speed possible:

• Long, narrow wings: the swift’s sickle-shaped wings create little drag for the lift they produce, which suits both fast flight and long glides.
• A streamlined body: the compact body, short tail and tiny legs reduce air resistance.
• Wings that change shape: a 2007 study published in Nature showed that swifts sweep their wings back for fast flight and spread them wide for slow gliding and tight turns. This “morphing” lets one bird be efficient at very different speeds.
• Powerful, quick wingbeats: swifts can flap rapidly in bursts, then glide, which helps them accelerate during chases.

High speed matters most during screaming parties and when escaping predators such as the Eurasian hobby, a falcon that can catch swifts in the air. At other times, swifts save energy, which is essential for a bird that flies for about ten months without landing, as explained in do swifts ever land?.

What about the white-throated needletail?

Many lists of fast birds name the white-throated needletail (Hirundapus caudacutus), a large swift that breeds in central Asia and Siberia and winters as far south as Australia. It is often said to reach 170 km/h (105 mph) in level flight.

This figure has never been confirmed. The methods used to measure it were not published, so no one can check whether it was airspeed, ground speed with a strong wind, or simply a guess. The needletail is a big, powerful swift and it is probably very fast, but until it is measured properly, the common swift’s 111 km/h remains the better-documented figure.

Fastest birds compared

The table compares the swift with other fast fliers. Diving speeds are very different from level flight, because a diving bird uses gravity rather than flapping power.

Ducks, geese and racing pigeons can also cover the ground at high speeds, but published figures often include strong tailwinds. For the full ranking across land, water and air, see our list of the fastest animals, and for the falcon’s record dive, read how fast can a peregrine falcon fly?.

Is a swift faster than a swallow?

Yes. Swifts and swallows look alike and both hunt flying insects, but the swift is clearly faster. Barn swallows hunt with agile, fluttering flight at moderate speeds, while swifts are heavier for their size, have longer, stiffer wings and fly with fast bursts and long glides. You can compare the two in our swallow vs swift guide.

How far do swifts fly?

Speed is only part of the story. Swifts are also champions of distance. A common swift flies at least 200,000 km (124,000 mi) a year, traveling from its nest in Europe or Asia to Africa south of the Sahara and back, and feeding on the wing every day. A swift that lives for 10 years or more may fly around two million kilometers in its lifetime, the equivalent of more than two trips to the Moon and back. Learn more about its life and migration in our common swift profile.