Group+3-12

Political Part done by Fessman
 * By Nolan and Logan and Colby**

Colby- do page 2 on pbs site Nolan- do page 3 on pbs site Logan- do page 4 on pbs site We discussed at the beginning of this project which topic would be best for both science and government. There is an exceptional amount of information in the scientific part of aviation, and the government piece of this can be seen as well through the innovations in the technology, as well as through the air traffic control with no fly zones and through the air force and the military.

Government Innovations in Planes Almost all of us have been there. We go on a vacation or have to travel a great distance for work or to see a family and in the process we find ourselves in the air! But how is this possible? How does a plane "defy" gravity and let us glide through air like its nothing? This can be described by something called Bernoulli's Principle. Bernoulli's principle states that when something is forced into a smaller area, usually in dealing with water through a tube and the water is moved into a smaller diameter tube, the "liquid" flow will increase in speed, and the pressure will decrease. The same goes for air, as it can be treated in its own way as a liquid for understanding such a concept. When the air splits across the top and the bottom of the wing, the curvature on the top of the wing forces the air to move faster across the top. The top of the wing now has faster air going across it than the bottom of the wing. Knowing Bernoulli's principle, we know that higher velocity creates lower pressure, so a low pressure will be above the wing, while a higher pressure will be below. This is generally how lift is created. The high pressure underneath creates a force on the wing pushing it upward. It can also be better understood when Newton's laws are taken into consideration. For every action there is an equal and opposite reaction. If applied to a wing and air, the wing must apply a force to the air. In return, the "reaction" is the air giving a force to the wing in lifting it. Taking this theory, Newton's law suggests that something must change for lift to happen. As it turns out, changes in the air's momentum will result in lift on the wing. In order for the lift to occur at a noticeable rate however, it must divert a LOT of air down through the wing. In the case of a wing on a plane, the lift of the wing is proportional to the amount of air diverted down times the downward velocity of that same air. The red arrow in the picture above shows the vertical velocity of the downwash of air on the wing as seen by someone on the ground. This arrow increases in length (increasing the velocity) when there is an increase in the plane's speed as well as an increase in the angle of attack. It can be seen from the ground that the downwash of air actually appears vertical, going down from the plane. Here is a picture of this phenomenon. Another very important part in how planes fly is in the fact that air has viscosity. It is much like water, just as it was seen with Bernoulli's equation above. When the air passes by the wing's edge, it is forced down in the downwash **because** it is like water! Have you ever taken a glass and placed it horizontally by a stream of water coming out of the faucet? Notice how the water's stream diverts itself around the cup instead of falling straight down. The same thing happens with air around a wing. This is another factor in how lift happens! Take a look below at the example explained: Above all, in a very brief statement, when power is applied through the plane's engine, the energy is transferred to the air, which causes the lift through the downdraft and the change in pressures. Now that there is a bit more understanding of just how planes work, lets take a look at some of the innovations and improvements that have been made over the years.
 * How do things fly??**


 * Wright Brothers Biplane**

In the year of 1903 the Wright Brothers have not invented flight but invented the ability to fly**,** their main goal was to develop the technique of controlling an air craft not just getting one in the air, they did this by using a privily owned wind tunnel then they calculated the forces that their Wright Flyer would have to overcome in order to stay airborne, and the means (a properly pitched propeller and wings that could be twisted to steer the plane) to do it.


 * The Rotary Engine**

The Rotary Engine was desinged by French engineers in 1908, the biggest problem before the Rotary engine was the massive weight of the engines in earlier years that made plains fly. The rotary engine, which used spinning cylinders that were cooled by the passing air and didn't require liquid coolant. The first rotary airplane engine produced a then quite respectable 50 horsepower and was so comparatively small and light that it was named the Gnome.

Airplanes soon became armies' "eyes in the sky," Early combat pilots tried shotguns, bombs, and fixed machine guns with little success. The easiest way to aim at another target during flight was to point the entire airplane at it -- but how do you fire a machine gun from the front without shooting off your own propeller? The answer: synchronize the firing of the gun to the movement of the blades. In Anthony Fokker's original design, a series of pistons prevented the machine gun from firing when the blades were in front of it. When the system was mounted on the Fokker Eindecker, it was transformed into the first true fighter plane.
 * Synchronized Machine Guns**

Although the idea that a bomb could be dropped out of an airplane was thought of all throughout the invention of military planes, it could never fully be achieved because the reality was that it couldn't really be done. The weight of a bomb in the cargo of a plane was far too heavy for it to stay in the air. However, in 1914, Igor Sikorsky, figured out a working plan for a heavy bomber that would actually work. This bomber was planned to have four engines and hold ten men. This was soon followed in 1917 by the Germans with the "Gotha". This plane alone killed hundreds of London inhabitants, and screwed up some of the economics. As mentioned before in how things fly, a lot of air had to be pushed through the downstream to keep the plane in the air. With the use of the special shaped wings, the angle of attack on the wings, and the power provided by the high efficiency propeller, this was made possible.
 * The Bomber**

At the University of Gottingen, Ludwig Prandl and his team invented a plane with one thick wing, instead of a bi plane kind of shape with multiple strips coming off the side. This idea with the thick wing allowed the newest planes to climb much steeper than before at a much greater angle, at the same time without losing any lift and stalling. This was a very innovative idea which is still used today. Only one wing was used, and this can be seen with all sorts of planes today, from fighter planes to commercial jets.
 * The Thick Wing**

Towards the beginning of World War II, Britain's Royal Air Force had a valuable tool to their advantage in the skies. Attached to their military planes was a new technology called radar. This technology used radio waves to detect incoming enemy planes from far away distances. Robert Watson Watt developed the British system, which would shoot these radio waves out of the plane and have them bounce back to the device, record them and see how far they are away. This is much like how sonar is used in submarines with sound waves. The sound wave would bounce off of something like the sea floor and come back to the device. The device would then measure when the wave is received and use the time it took to come back to find out the distance it was from the sea floor. To go a little more in depth, the same is seen in radar, where the machine knows how fast the radio wave is. Since it receives the radio wave back in a certain amount of time, it can use position=velocity x time and figure out where it is located with respect to the plane.
 * Radar**

At the the end of the second world war, piston engines could not keep up with the 500 mph speed the plans were going. This problem sparked the jet engine, which ignites a mixture of fuel and compressed air to create explosions that generate thrust. The concept had actually occurred to designers even before the First World War, but Britain's Frank Whittle and Germany's Ernst Heinkel made it a reality. Germany quickly became the front-runner, producing the revolutionary twin-jet Me-262 fighter, which had a maximum speed of over 550 mph, 100 mph faster than the fastest Allied plane. The piston engine had clearly had its day. Here's a video on how jet engines work! Take a look! media type="youtube" key="xszY7GJMxnE" height="283" width="496"
 * The Jet Engine**


 * Supersonic Flight**

A sonic boom was a major problem for aviation. Planes kept getting faster, and eventually they would be fast enough to catch up with their own sound waves, causing a sonic boom. Scientists developed all moving tail pieces that could better handle the supersonic speeds. Before these new innovations were added it was much more difficult for planes to keep control. Now that this has been added to the fighter planes, it is much more stable to have a sonic boom in the air.

The main rotary blade on top of the helicopter's body is the main factor that keeps the helicopter in flight. Each blade works similar to that of a wing on a plane, creating a force that pushes up on the wing, thus forcing the entire helicopter upward. Increase in the RPM of the blades creates an increase in lift, because as it was discussed before in how flight works, a greater speed (application of power) creates a greater lift. The stabilizer is also a very important part in the helicopter. It sits above and across the main rotary blade, dampening unwanted vibrations and keeping the body of the helicopter stabilized.
 * The Helicopter**

**Targeting Systems** As the aircraft over the course of history became faster and faster, a simple gun sight by itself made it very difficult to hit an enemy plane, so innovation was needed. During the Korean War, the North American F-86 Sabre solved this problem by putting a radar powered gun sight in its system. This was done by putting a radar antenna in the nose of the Sabre and obtaining the target's range. The latest of the fighter planes out there now use infrared systems head-mounted on the planes to literally follow the movement of an enemy fighter aircraft, and shoot it down in this way. **The Surface-to-Air Missile** The increased altitude and speed of enemy aircraft over time not only made it difficult for simple bullets for guns to hit planes, but also for missiles to hit. Simple anti-aircraft surface missiles could no longer hit the planes, so a thing called a SAM was invented. These missiles have a lot more pop, racing at a much greater speed than that of the previous missiles, and fighting off gravity at a greater rate to get into the sky to hit the target on its way. There are a variety of these missiles, however the two main ones include heat seeking and radar guided.

Take a look at this word document for a lot more science info on modern planes by Logan:


 * Where the Government comes in:**

With the utilization of aircraft in modern war, nations have established No Fly Zones (NFZ), which serve as a sort of DMZ for the sky. The political and military decision to establish NFZs can be controversial itself. One notable example would be in 1991, following the Gulf War. The United States, France, and Great Britain established two NFZs over Iraq to protect Kurds and Shiites from Hussein - without approval from the UN. NATO also established NFZs over Bosnia and Herzigoniva. The idea of no fly zones was a heated issue during the Libyan rebellion, when multiple UN members debated whether or not to establish some to protect rebel forces from Gaddafi's forces.
 * No Fly Zones**

Particularly following the 9-11 terrorist attacks, airline security has been an increasing issue. The Transportation Security Agency (TSA) oversees airline regulation, and has instituted a large number of new rules in light of the attacks. For example, pilots may now be armed on planes, and cockpit doors have been fortified to prevent forced entry. The infamous liquid limitations, shoe removal, and body scans are also post-9-11 amendments to airline security laws. The TSA itself has seen an employment increase of near 50,000 people as well. These decisions are controversial themselves, as many people question where the line should be drawn between security and privacy.
 * Air Security**



The advancements in airplanes has completely revolutionized the way in which wars are fought. Synchronized machine guns (mentioned earlier) were just the start. Today, we command such planes as the F-22, a fighter jet capable of reaching the speed of sound and holding approximately 4500 kg of weaponry or the T-50, a jet that can wield 57mm ZiS-8 ammunition. War is no longer a matter of troops so much as technology, and as much innovation we see in commercial airplanes, there is more in the military sector, trying to keep up with the advancements in weaponry.
 * The Airforce**



http://www.theweek.co.uk/politics/7223/iraq-libya-history-no-fly-zones http://www.farecompare.com/ask-rick/are-we-safer-in-the-air-since-911/ http://www.tsa.gov/ http://www.google.com/imgres?um=1&hl=en&sa=N&biw=1222&bih=691&tbm=isch&tbnid=pH0RuNDXK5RPhM:&imgrefurl=http://www.tsa.gov/approach/tech/ait/how_it_works.shtm&docid=JO1CQVLGReJwiM&imgurl=http://www.tsa.gov/graphics/images/approach/backscatter_large.jpg&w=900&h=576&ei=syrET4alJaj40gHiwpCuCg&zoom=1&iact=rc&dur=462&sig=101178940240824424953&page=1&tbnh=124&tbnw=193&start=0&ndsp=18&ved=1t:429,r:0,s:0,i:140&tx=73&ty=23 http://www.airforce.com/ http://sk.wikipedia.org/wiki/Suchoj_T-50_PAK_FA

http://www.allstar.fiu.edu/aero/airflylvl3.htm http://www.pbs.org/wnet/warplane/topicfeature.html