How Planes Stay Up In the Air
I remember a picnic with Becky, my girlfriend, at Maidu Park five years ago. We lied on the lush green turf and held hands as we watched the clouds drift by. We were captivated and intrigued by the definitions in the clouds as we matched them to shapes of animals and other objects. She pointed towards a blanket of clouds on the right and said, “There! That one looks like a dragon.” Right at that moment, a plane flew right above us as it cut through clouds. She quickly sat up and followed the plane with her head. Her eyes widened and her eyebrows shot up as she burst out, “Wow! How do you think it stays up in the sky like that?” As any mischievous thirteen year old would, I simply the magic dust and invisible angels carried the plane on their backs. She laughed and called me stupid for not knowing the answer. However, now as a college student embarking towards my future, I made my personal goal to be a pilot and learn about planes. I got accepted to Embry Riddle, an aeronautical school in Arizona, straight out of high school. Although the fear of planes falling out of sky held me back; so I decided study at Sierra College until I’m ready.
Sean palmer, a sophomore at Sierra College, flys planes for a hobby. He pointed out that, “Flying a plane is not like driving a car, it’s far more complicated, but at the same time fun… I fly almost every week, but it’s little expensive to rent planes. So, I’m saving up for my own Cessna 120 for almost two years now but it’s feels like ten years” (Palmer). However, the history of flight goes back more than a century. “From the earliest times, the desire to fly has been a powerful urge. Although people could walk, swim, or travel by ship or carriage, for centuries they were frustrated by inability to emulate birds” (Mondey). That urge cost people their lives as many made attempts to fly, but most failed. However they all had the same idea of birds being the key. “People strapped themselves to wings and jumped off cliffs and other simply watched the birds fly as they took notes. Some studied the feathers from birds and theorized that feathers glided light enough to defy gravity, and others just deemed flight far too dangerous to even attempt” (Prewitt). Stephen Mathew, a plane engineer now attending Sac State for his BA, notified, “Most people got mislead that birds fly by moving their wings downward and backward in a rowing motion rather than an up and down motion as we know today. That’s probably one of the reasons why the invention of flight took so long as it did.”
In the book “Flight”, H. Stever points out that the final blueprint of a plane takes into consideration the four basic essentials of flight: aerodynamics, propulsion, structure, and control. Those principles incorporated enable airplanes to overcome the force of gravity and therefore fly. (53) Aerodynamics, which consist of four basic principles: Lift, drag, thrust and weight work together with the wings of the plane. In an interview with Verlin Wolfe, pilot and son of Mr. Wolfe from Wolfe Aviation in Stockton said that the wings are the most crucial aspect of an airplane’s lift. “Aircraft wings are the most crucial part of lift. The wing slices through the air and the curve at the top of the wing causes air to go faster than the bottom of the wing which is flatter to cause air to go slower. Therefore, this creates lift”(Wolfe). Fast air has low pressure than slow air. Meaning there is high pressure on the bottom of the wings (Wiley). This difference causes “The high pressure at the bottom to overcome the top and pushes the wings up (Airboyd).
The wings give the plane lift, but the weight of the plane as a whole keeps the airplane balanced with the lift. Endless lift but no opposing force to maintain how far up a plane went would cause catastrophic results. “The weight of the plane involves gravity which pulls the plane downward. Lift keeps it up and the weight helps maintain balance” (Down). However, there is more to weight which plays an important role in keeping the airplane in the sky. Neil Ardley, author of “Air and Flight”, describes the front of the plane and the back of plane including the luggage and passengers to be proportionally balanced to sustain safe flight (33). Sometimes people are asked to leave a flight if the plane looks overloaded. Even weight sensors on board read the stability of the plane. Stephen Robinson, an aeronautical engineer from UC Davis Mechanical and Aerospace Engineering department mentioned that, “Planes nowadays have weight sensors, but it’s the pilot who is in charge of making the calls” (Steven). Wings alone do not guarantee lift, but rather the angle that it cuts through air. The Wright brothers understand the importance “By testing wing models in primitive wind tunnels, they made progress on the problem off lift/drag” (Angelucci 17). Both Mr. Stephen and Mr. Wolfe empathized the importance of angle of attack on lift. They believe the angle of attack helps the angle at which the wings slice the air. In which the pilot has the ability to control lift and sustain the plane safely in the air (Stephen, Wolfe). Mr. Wolfe mentioned, “The top of the wing has to be at least 50% longer than the bottom so there is lift, but usually there is only a difference of five percent in real planes because angle of attack does the work.” (Wolfe)
Angle of attack maintains lift and gives the plane the upward motion; however, thrust, the second aerodynamic force, helps the plane move forward. Gravity pulls the plane down, but with the combustion of lift, thrust makes the plane fly through air. “Most of the time it’s either propellers, jet engines or rockets that drive the plane forward” (King). That forces “… a mass of air to the rear, behind the plane” (Crane). Bigger the engine, bigger the thrust because of more air pushed out the back and through the exhaust of the plane which causes bigger thrust (Machado). However, to stop the plane from spinning out of control, “drag must be equal to thrust” (Wilkins). Meaning, during landing and takeoff the thrust to drag ratios are different. Although during flight the thrust to drag ratio always equal each other. (NASA)
Thrust helps the plane to travel forward; however drag, the third aerodynamic force, causes the opposing force that works against thrust.”Drag is the aerodynamic force that opposes an aircraft's motion through the air.” (NASA). The two main drag forces that affect how planes stay up in the air consist of “…Induced drag and parasite drag” (Stephen). Induced drag strains against the lift being produced. So, the wings cut through air, but slightly force downward by the inseparable force called induced drag (Fernandez). “Parasite drag, like it sounds, is bad! This type of drag is the overall force of air fluid that’s against the planes movement” (Crouch). However, drag with all the other forces combined keeps the plane in the air. ”Sometimes air fluid also plays a role in the amount of drag to help planes benefit from the force that pushes it against thrust. The drag forces attack the planes, but air fluid passes to the back of the plane and slightly pushes it like trust” (Walke).
Where the air is smooth, the drag force is considerably less than in the turbulent portion of the boundary layer. It is obvious, then, that if the boundary-layer flow could be kept laminar, there would accrue a tremendous benefit to airplane performance. The airplane’s engine would not have to expend so much of its power overcoming boundary-layer drag, and the available power could be utilized more efficiently to provide greater speed, range or payload. (Stever 56)
Aerodynamics helps the plane sustain flight in air, but the shape and design of the plane connects each aerodynamic force to work collectively with each other to sustain balance (Wolfe). Sean Palmer invited Becky and I to fly a plane with him and his instructor. That weekend, we drove out to Executive Airport in Sacramento with Sean and met instructor Clemens, who insisted Becky that flying a plane is much safer than driving a car.
Sean powered his fist and roared, “You all are going to love this!” as he hauled a rented Cessna from the shed. While we waited for Sean and the instructor to do the safety checks, Becky and I did a quick 360 around the plane. The sun gleamed over the Cessna and the glossy paint on the plane reflected back like a mirror. Many sharp edges made the plane, but each sharp edge connected smoothly with each other. Even the rivets that held the pieces together on the outside of the plane perched smoothly to the rest of the surface. Becky shook her pony tail as she brushed the smooth wings of plane, and Sean quickly glanced at her and said, “Oh yeah, it’s smooth all right! Even the paint and type of metal helps keep the plane in the air. The discovery of new metals made it possible to be sleek and aerodynamic when it comes to flight” (Palmer)
In the past 20 years many new structural methods have been introduced, either to save weight, save cost or meet the difficult demands of highly supersonic in which the whole airframe is heated by kinetic effects, which can loosely be thought of as air friction. One of the first major answers was the introduction of a new metal, titanium, which is slightly heavier than aluminum but much stronger and well able to retain its strength at raised temperatures. (Mondey 55)
After another 20 minutes of safety checks, air traffic control granted runway access. We finally got inside the plane; Sean sat on the left, and the instructor sat on the right. This plane made for teaching flying had two yokes (control wheel), but the instructor sat there with his hand crossed since Sean had more than 150 hours of flying experience. As the plane started to roll, Becky and I held hands. At about 50 miles per hour, Sean yanked back on the yoke and the nose of the plane dashed 40 degrees up and we slowly gained flight. My eyes widened and trembled with amazement at how even a small plane can fly. Becky on the other hand, shrugged her shoulder and gave me a smile while she played with her hair. She glanced down the window as she tossed her hair and shouted, “Wow, this is amazing!” Within a few minutes, we were high up in the sky, and Sean began steadying the plane. After a while of steady altitude gain, the instructor asked Sean to do the maneuvers that he taught him last time. Sean without hesitation yanked the plane back and flew straight up into the clouds. He let the plane hang there for a second -- and then let it fall 90 degrees down. I held onto Becky with one hand and held the side of my seat as the seat beat held us from flying forward. Instructor Clemens turned around and pointed out that the shape of the wing helps the plane stay in the air. He said, “There is a reason that the planes look like birds. The nose of the plane and the sharp smoothed outer edges all around the outside of the plane help it cut through air. Without this shape drag would take over and flight would be close to impossible” (Clemens). Aerodynamics sustains flight; however, skilled pilots trained for the worst specialize in keeping the airplane airborne at even the worst scenarios. “All pilots must have at least 2000 hours of flying experience with an instructor to even be eligible for a pilot license. They must prove they can keep an airplane in the air safely” (Clemens). As any pilot trained for the worst, each one must acquires the finest training in a stall, the most dangerous situation in flight. Stall occurs when “…angle of attack is too steep where air can no longer flow over smoothly” (Crane). According to Bob Schmelzer, mastering a stall demands the pilot to have complete control of aircraft attitude, flight path, speed, directional control and even stall speeds (21). Julie walker, author of A whole new world says, “It’s when the wings go on a strike and cease to produce enough lift for flight…to remain stall-free, don’t fly too steep or bank slowly.”(38)
Sean constantly monitored the control panels almost every other second. As he a maintained flight altitude and steady control over the yoke, he leaned back and questioned me what he should do next. I gave him a quick glance as I shook my head and pleaded, “Nothing! Please, just land already.” He hunched over and looked out the window and then he quickly looked at the instructor for approval, who winked back at him immediately. Sean spun the plane around and jammed the yoke down. A pain of panic stabbed my chest; I saw nothing but an empty soft field as we dived down. Becky frantically scrutinized for any runways nearby, but Sean calmly held both his hands on the yoke and roared, “Oh Yeah, we are going to land here!” He sat up sat and hunched forward as he began descending towards the field. He yanked the throttle down and to stop the engines. The plane automatically began to glide down, and Sean controlled the flaps to full drag. We flew inched above the surface for 20 seconds and then Sean slowly inched the yoke down bit by bit. The main wheels at the back touched the surface, and Sean elevated the nose wheels down. Me and Becky held onto the metal bar in front of the seats and braced for the rough landing. However, that assured as safety began panting as the plane taxied to a stop.