They test it in the wind tunnel. If the design fails to pass the test they make an another design. By testing and testing they come up with the design at last.
Drag slows down aircraft, which is why designers of aircraft that are supposed to be fast pointy and waisted, because a pointy shape has less drag, and waisted because of the area rule, which also helps an aircraft to go faster.
Many formula 1 racing car designers and aircraft designers have found the teardrop to be the most aerodynamic shapethe teardrop or raindrop is indeed the most aerodynamic shape at subsonic speeds.At supersonic speeds the so called "Sears-Haack body" has better aerodynamics.
Airplane designers have been influenced by the study of birds through examining the different qualities of their wings. The strong bones of the birds that are very light help determine the necessary weight restrictions and alloys used in wings. The shape of the wings of birds shows them how to shape airplane wings for maximum lift.
The shape of the fuselage of a modern aircraft like a Boeing 747 would be described as cylindrical.
Designers need to understand the depth, width, and height part of the shape. ^_^ this is also that they won't get the wrong measurements.
round shape
Yes. How else would they get the right size and shape?
To answer your question directly: yes. An aircraft operates by altering the direction and pressure of a fluid (in this case air) to produce lift. Infact, simply put an aircraft designer alters the shape of the aircraft to control these changes in directions and pressures to control how the aircraft produces lift.
If you already know the basics of crochet, you can use the knitting instructions to determine the size and shape you need. You would have to experiment to get the correct gauge.
The shape of the aircraft makes it aerodynamic.
It is a 3 dimensional shaped object
The water drains on the aircraft usually pops out under its belly because of the streamlined shape of the aircraft.