Small aircraft can also be unattractive to airport managers, as they carry fewer fare-paying passengers and are more sensitive to wake vortices created by larger aircraft (thereby taking more of the scarce capacity time).
Instead, when swimming upstream, they conserve energy by using vortices, or miniature whirlpools, that form where the water flow is disturbed by rocks, branches, or other objects.
The runway capacity corresponds to the maximum number of aircraft landing and/or taking off, taking into account physical constraints which have an impact on safety like wake turbulences vortices.
Aeronautical engineers already knew that delta-wing aircraft (so-called because the wing resembles the Greek letter Δ) produce vortices at their wingtips, which create lift.
But now that they know how vortices provide lift for insects that flap their wings, they want to study how to exploit this phenomenon in the design of propellers and helicopters.