# Mother nature perfect flying machines

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Mother Nature
Perfect Flying Machines

Due Date: March 5, 2010

Introduction 3
Problem 1 4
Problem 2 5
Problem 4 6
Problem 5 7
Problem 6 8
Problem 7 9
Underwater birds: Penguin 9
Birds that fly over water: Pelicans 9
Birds that fly at land: Condor 10
Birds that fly at height altitude: Eagle 10
Problem 8 11
Problem 9 12
Section 2.3 : Equation ofStage for a perfect gas 12
Section 2.6: Anatomy of the Airplane 12
Conclusion 14
References 15

Introduction

Birds and airplanes fly for the same reasons. If we looked at the shape of a bird's wings, we would see they are curved the same way airfoils on airplanes are. When a bird glides during level flight, it stays in the air just like airplanes do its wings provide the lift.
Thedominant aerodynamic forces that affect flight are lift and drag. The difference in the pressure of air above and below a wing produces lift. When a bird holds its wing at a sight angle to an air current, air flows faster over the upper surface than it does over the lower surface, thus creating less pressure above the wing than below it and causing lift. At the same time, drag, or resistance to tothe moving air, drags the wing backward. The combined effect of these two forces lifts the wing and drags it backward.
While most of the lift on a bird's wing comes from the low air pressure on its top, a certain amount of lift is generated from beneath by air striking the undersurface of the wing. Air flow in the under side stops at a point close to the wing's front, or and then gradually speedsup until it is near the back, or trailing edge, by which time it has reached the same velocity as the air traveling over its upper surface.
If the front edge of the wing is tilted upward just a little bit and is placed in the air stream, the air will strike the bottom surface more directly, there by increasing the lifting force on the wing from below. The more the wing is tilted upward, themore lift it will get, but only to a certain point, when the angle of tilt approaches the vertical, the air pressure against the bottom surface begins to push the wing backward rather than upward. If the wing is tilted too much, the lifting force eventually vanishes and the drag is so great that it stops the bird's "buoyancy," or forward movement. This results in what is commonly called a stall, andthe bird must regain the proper wing angle and flight speed or it will crash.

Problem 1.) Discuss the anatomy of birds (feather, internal organs, bones, tail, size/weight, etc) and why they are such excellent flying machines.
Birds have a light skeletal system and light but powerful musculature which, along with circulatory and respiratory systems capable of very high metabolic rates andoxygen supply, permit the bird to fly. The development of a beak has led to evolution of a specially adapted digestive system. These anatomical specializations have earned birds their own class in the vertebrate phylum. The avian respiratory system delivers oxygen from the air to the tissues and also removes carbon dioxide. In addition, the respiratory system plays an important role inthermoregulation (maintaining normal body temperature). The avian respiratory system is different from that of other vertebrates, with birds having relatively small lungs plus nine air sacs that play an important role in respiration (but are not directly involved in the exchange of gases).
Feathers are one of the most prominent features of a bird's anatomy, and they are unique to birds. Every bird hasfeathers and everything that has feathers is a bird. Feathers perform a number of functions for a bird. Firstly, they provide insulation, this is very important in a warm blooded animal (body temperature of most birds is maintained at around 40C). It is believed by most scientists that this insulating effect was the primary force driving the evolution of feathers, i.e. ancestral birds developed...