The airspeed would be roughly 11 meters per second (15 beats per second * 0.73 meters per beat).

Mr. Obvious: Unladen swallows have an airspeed velocity of about 10 meters per second. Some species, however, can achieve velocities of 15 meters per second.

an African Swallow would tend to travel at a different velocity than an European Swallow. Furthermore, their flight patterns are different, so their instantaneous velocity at a given point will almost always be different

However, technological advances have given way to being able to use swallows to transport husked coconuts across large distances, enabling us to use coconuts on a daily basis, provided we have a large contingent of willing swallows

Swallows can also be modified, as attaching a 50 newton rocket propulsion system on a 1 kg swallow will result in an acceleration of 50 m/s(2), which is of course negating any air resistance