From Icarus to da Vinci and to Wright Brothers

Classification writing I composed in the teacher training program at Busan University of Foreign Studies in fall, 2012.

I remember googling a lot to write about this topic. I was serious about the writing class and wanted to write a challenging topic every time. I initially wanted to write about Greek+Roman mythology or gods, but it wasn't classified well. So I changed the topic to aircraft. At first, I vaguely thought this would work. There were things I didn't know about this topic. I ultimately learned lots of things, working on this topic. 


     From Icarus in the Greek myth, to Leonardo da Vinci in the Renaissance, to the Wright Brothers in modern times, mankind has longed to fly as free as a bird. People have developed various aviation vehicles, which help transport humans and supplies. These aircrafts are divided into two categories: One is buoyancy-based craft and the other is aerodynamic-based craft. Buoyant aircrafts are lighter than air and include hot-air balloons and blimps. The airbags of the inflatable objects are filled with heated air or light gases such as helium or hydrogen. These devices are able to float since the air or gas inside the bag has a relatively lower density than its surroundings outside the bag. Hot-air balloons are mainly used for the tourism industry, and blimps for advertisement at major sporting events. On the other hand, aerodynamic aircrafts are heavier than air, but they generate enough lifting power to be able to fly because of the wings. This group splits into two subcategories: fixed wing and rotary wing. Regular airplanes, hang-gliders, and paragliders belong to the fixed wing craft, whereas helicopters belong to the rotary winged craft. When an airplane speeds up, the air pressure beneath the streamlined wings is higher, and thus this force pushes it upward; When a chopper’s rotary blades spin, the shape looks like the wings of an airplane. The air flows more quickly over the top of the blades than it does below, and thus the chopper lifts vertically. Airplanes and gliders are used by passengers and holiday-goers respectively; helicopters are largely used for emergencies and military uses.