| Airframe Essay, Research Paper
I am interested in aircraft, especially airplane engines and structure. I have studied for five years in Japan about aviation maintenance at my high school and my college which have aeronautical engineering departments. Needless to say, I am majoring in the aviation maintenance technology. Aircraft are eminently related to physics. I therefore chose this book, gAirframe h. I think that a person who is interested in aviation would feel interested in this book. I have already studied about some flight dynamics in Japan. I am therefore going to write about lift and a stall, wing curvature, axis of an airplane in flight, and my doubt in the book.
The book gives an example of an airplane bound from Hong Kong to Dallas, TPA 545, which stalled on its way to Dallas. The circumstance was that the plane suddenly descended and went up, then it stalled and went down again. However, the pilots of the plane recovered the airplane fs balance and altitude, and the airplane made an emergency landing at Los Angeles airport. I am going to write about the reason why airplanes can fly before I write about a stall, because it is easy to understand a stall when the physics of flight are understood. Airplanes can fly by making use of lift. Air usually flows are both the upper and lower wing fs surfaces. There are differences in airspeed and air pressure between air flowing over the upper side and air flowing under the lower side of a wing. The air flowing over the upper side is faster than the opposite sides air, and the air pressure on upper side is lower than the opposite air pressure. The power to lift up, which is called lift, therefore acts on the wing, and the phenomenon is known as Bernoulli fs principle. These are the reasons why airplanes can fly.
A stall is caused by exfoliation of air on a wing. I think that there is some possibility of any airplane stalling from this phenomenon. In my opinion, the airplane was falling for some reason or other, then it climbed steeply to regain its altitude. However, its rise angle was too sharp, therefore it stalled. If a wing takes a high angle, the air flowing the upper side of the wing comes off the wing and makes curls of air. This makes drag to the airplane. In that case, the wing cannot make lift and then the plane falls down. The phenomenon is called a stall.
Why airplanes can fly relates to the lift and the amount of curvature of a wing. I have already mentioned the lift. I am therefore going to write about the amount of curvature of a wing. I think that many people who have flown planes or been at airports have seen that when an airplane takes off or lands, the back of its wings, which is known as a flap, is down. The wings can make the lift while the airplane is flying at high speed. However, the airplane cannot reach the speed that its wing needs to make the enough lift when it takes off and lands. The airplane therefore needs to increase the amount of curvature of its wing to create enough lift. A wing which has a greater curvature can make lift more than a smaller curvature at low speed. However, the wing of greater curvature is disadvantageous at high speed because it makes drag. Therefore, the airplane puts its flap down when it takes off and lands and it puts its flap up when it flies at high speed.
The investigators mentioned in the book who were trying to find the cause of the trouble referred to pitching rolling, and yawing. These motions are very interesting to me. I think that land and marine transportation such as cars, trains, and surface ships have only yawing movement. I think that only aircraft can make various moves by using rolling, pitching, and yawing. Whenever an attitude of an airplane changes in flight, the airplane will rotate about one more of the three axes. Acrobatic airplanes and fighters are designed for making quick turns more than passenger and cargo planes.
Motion about longitudinal axis of an airplane is roll and is produced by movement of the ailerons located at the trailing edges of the wings. Lowering the aileron on one wing and raising the aileron on the other causes roll. The wing with the lowered aileron goes up because of its increased lift, and the wing with the raised aileron goes down because of its decreased lift. Thus, the effect of moving either aileron is aided by the simultaneous and opposite movement of the aileron on the other wing.
Movements of elevators at rear of the horizontal tail assembly causes pitch movement, which rises on lowers the nose of the aircraft. The elevators are hinged to a fixed surface, the horizontal stabilizer. The horizontal stabilizer and the elevators from a single airfoil are together. A change in position of the elevators modifies the shape of the airfoil, which increases or decreases lift.
The movement of the yaw axis is yaw and is generated by movement of rudder located at the rear of the vertical tail assembly. The rudder is a movable surface hinged to a fixed surface which is the vertical stabilizer or fin. The nose of the airplane turns the right if the rudder moves to the right, and if the rudder moves the left, the nose also turns to the left. We can usually see this yawing motion everywhere.
I have my doubt about catchword of this book. There was an airplane accident, the explosion of its left engine, at Miami International Airport, and Casey referred to the accident. The misadventure was made by unsuitable maintenance, the left wing absorbed flying splinters, and protected the passengers in the cabin. However, I cannot agree with his opinion. The airplane would explode if the flying high temperature fragments by the engine explosion went through the wing or did not go through the wing. The airplane explosion is unavoidable because they could damage the fuel tank which causes explosion. Usually, airplanes have fuel tanks in their wings. One of the reasons is efficient utilization of fuselages. Other reason is to reduce vertical motion of the wings. The wings make lift, and the power lifts up them. However, when the airplanes are on the ground, gravitation pulls down the wings. There is a vertical motion on the wings. This motion makes metal fatigue to the roots of the wings. This fatigue can sever the wings from the body. If airplanes have their fuel tanks in their wings, they can lessen the vertical motion and prevent the metal fatigue. In my opinion, although high temperature fragments by the engine burst damaged the left wing which has a fuel tank, fortunately all of the passengers did not be killed by the accident.
I think the author knows about airplanes, and his book, gAirframe, h refers to flight dynamics accurately. I was surprised when I read the book because lift is fully explained in the book. I therefore referred to the lift and the stall, the amount curvature of a wing, and three axes of airplanes. Airplanes make use of the lift to fly and they use the three axes to make turns and gain or lose altitude while flying. There is every possibility of an airplane stalling while it is flying. The stall is caused by exfoliation of air on a wing. I might find a doubt in the book. However, I do not care the doubt because this story is fiction. I have read fiction related to airplanes, however many of them are incredible stories. I read this fiction book with interest. This was an interesting book in English.
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