Page 8 - September 29, 2021
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{ 8 }  SNJ Today  |  SEPTEMBER 29, 2021                                                                                                                                                                                                                    SEPTEMBER 29, 2021  |   { 9 }

             Flying is for the Birds

              Human flight has been inspired by birds
                  and their remarkable adaptations.

      NATURE AROUND US                  J. Morton Galetto, CU Maurice River

           rowing up I remember that any
           movies about the invention of flight
     Gfor human transport included the
     Wright Brothers as well as a man who
     donned wings. His venture, from my recol-
     lections, involved feathers strapped to his
     arms and a leap from a structure onto the
     ground, resulting in a balled-up mess of
     plumes. I don’t recall a name being associ-
     ated with this botched attempt, but then
     history remembers successes better than
     failures. However, a reminder for children
     is that you can’t hit a homer if you don’t
     swing at the ball.
        So clearly not everything with feathers
     flies. In fact some birds with feathers don’t
     fly and other animals fly that have no feath-
     ers, as mentioned in last week’s article—
     bugs, bats, and fish (well, sort of).
        As for our nameless inventor who   An osprey holds its primary and secondary wing feathers tightly to-
     donned wings, you can rightfully conclude   gether and its tail closed for speed. PHOTOS BY AUTHOR
     that his arms, and yours, lack the proper
     profile to allow airborne flight. There are   By fanning its tail and wing feathers open an osprey initiates a stall
     people who do sometimes wear wingsuits   over the bander to protest its visit. The tail is often used like a rudder   These chicks, about two weeks away from making
     called BASE jumpers, BASE being an acro-  for direction in flight. Note the band on the right leg.         their first flights, face the wind. One exercises
                                                                                                                  its wings as it considers jumping overboard.
     nym for the objects that they propel them-
     selves from—buildings, antennae, spans   it possible for birds to become airborne,   cactus, gourds, and a plethora of other sur-  weeks of age they start floating up and low-
     (bridges), and earth, primarily cliffs. BASE   inducing air to move faster above the wing   faces. Examining some species will give you   ering back to the nest. They exercise their
     jumpers reach speeds up to 120+ miles per   than beneath. The pressure on the upper                           wings a lot in preparation for their first
     hour, called terminal speeds and for good   surface is less than beneath, which creates   insight into these factors.  solos at seven to eight weeks of age.
                                                                                 Common loons are skilled flyers who
     reason. In checking out this activity online   the force we term ‘lift.’  can reach speeds of 70 miles an hour, while   Ospreys, like other hawks, also make use
     I found there are lists of “the departed”   To achieve take-off there also needs   a few other waterfowl can do so as well. But   of high perches; thus they can rely on glid-
     associated with this sport. That’s one good   to be thrust. An airplane relies on engines   for lift-off they need a long watery runway.   ing, thermals, and flapping. Young osprey
     reason why I’ll stick to birds for this article.  while the bird relies on muscles and flap-                  who are not used to flight are often found
        There are lots of aerodynamic factors   ping. Birds’ chests are designed to accom-  In fact they can only achieve flight over
     that are important for achieving lift-off and   modate a lot of muscle, and they are also   the water’s surface. Occasionally you hear   exhausted on the ground or on docks and
                                                                                                                   are unable to get airborne. In these instanc-
                                                                               stories of loons who at night mistook a wet
     birds have many physical attributes that   relatively lightweight and streamlined to   roadway for a pond, landed, and then need-  es they are susceptible to predation and
     allow them to achieve flight. Their wings,   further enable flight. Their feathers are   ed transport to a body of water—always   elements, but if allowed sufficient time to
     like those of planes and insects, are basically   light but strong. The ratio of body to wing,                rest they are normally able to achieve flight.
     airfoils, curved surfaces that are designed   wing shape, feather placement, their foot’s   assuming that hanging out on the roadway   Experienced osprey can fly from a low sur-
                                                                               didn’t leave them like our departed human
     with a favorable ratio of lift to drag to allow   design… all determine many things, such as   jumpers.       face and even after submerging in water.
     flight. The body or fuselage shape can   how they achieve their take-off and land-  CU Maurice River’s experiences with   They are often said to be the only bird that
     reduce drag and make flight easier as well.  ing, how much they perch, how often they   osprey have taught us a great deal about   can shake off water in flight.
        A bird’s wing is wider where it connects   soar, and how long they can soar, among                            So larger, heavier birds prefer to rely
     to the body and tapers near the tip. The   other characteristics. In considering how   flight. At about six weeks of age the chicks   on soaring or gliding to get started, and
                                                                               begin to face the wind, which aids in lift.
     leading edge is thicker than the trailing   they achieve their flight, think about those   Just try launching a kite with the wind at   they also position their wings to create an
     edge. The wing shape and feathers make
                                          BASE jumpers and now add water, trees,   its back—likely impossible. At around seven   updraft. Small songbirds depend on rapid
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