On my quest to determine how efficiency in planes can be increased, one major issue must be understood. The weight of a plane restricts a plane from expressing its true potential and requires engineers to develop solutions where benefits can be made to a plane, without increasing the mass. All airplane designers must construct parts that meet all functional requirements of a plane, while reducing the weight of the plane as much as possible. Less weight permits less thrust to be used, thus decreasing fuel consumption. One way to reduce the mass of an aircraft is to reduce the mass of its material composite, while still having it serve as a sturdy exterior.

Originally, commercial transport aircrafts were made with an aluminum skin over an aluminum frame. Aluminum proved to be a decent material composite for planes, due to being light and being strong when alloyed, until several side effects were encountered. These side effects were corrosion and metal fatigue. Recently, a carbon fiber reinforced plastic, introduced in the Boeing 787, proved to be a lighter weight, corrosion proof, and sturdier replacement for Aluminum. Steel is also a material composite used in planes due to being four times stronger and three times stiffer than aluminum, but is also three times heavier. Steel is commonly found in the landing gear of planes where strength is required and it has also been used in some high speed airplanes due to holding its strength at higher temperatures. Different metals are being alloyed in order to improve the power to weight ratio in aircrafts for the performance of aircrafts to improve while experiencing fewer costs.

The use of material composites allows planes to have an exterior with a lighter mass and to be even stronger when facing harsh weather conditions. Graphite-epoxy consists of strong fibers fixed in a resin and thin sheets of the fiber can be stacked in multiple ways to achieve a certain strength or stiffness. Graphite-epoxy is as strong as aluminum, but weighs have as much, promoting a greater power to weight ratio. 

Another composite found in the structure of planes is titanium. Titanium is about as strong as steel and weighs less and is able to maintain its strength at high temperatures, as well as resist corrosion more than steel or aluminum. The Lockheed SR-71 Blackbird, the world’s fastest jet propelled aircraft, possesses an airframe that is composed mostly of titanium and alloys which enabled it to travel at greater speeds and at higher altitudes, without its exterior corroding or weakening. 

       There are multiple methods in increasing the efficiency and thrust of an aircraft. Using a ducted propeller rather than a traditional propeller is one of these ways. A ducted propeller is able to provide more thrust for the same amount of power (or requiring less power to achieve the same amount of thrust), elongating the life span of batteries and flight times.

       As the propeller rotates, air is pushed to the outside. Low pressure of the air flows over the top of the propeller, while high pressure flows over the bottom of the propeller. However, as the low pressure and the high pressure flow over the propeller, both pressures collide, forming a vortex. This vortex generates noise and heats up the air due to being wasted energy.

       A ducted propeller reduces this wasted energy. The wall encircling the propeller prevents the vortex from forming and uses the energy to generate lift. This is more efficient because the wall encircling the propeller enables more lift to be generated when using a smaller amount of power, thus pushing the aircraft more.

       The design of a ducted propeller is also able to increase efficiency by bending the laws of aerodynamics towards its favor. The lip, also known as the rolled edges, of a ducted propeller increases the amount of lift generated. The lip allows air to flow over a curved surface which causes the pressure to decreases, due to an increase in air flow. High pressure pushed the back of the lip, generating thrust and lift.

       Although the design of a ducted propeller may increase lift and thrust, it also increases the mass of the plane, causing the planes weight to increase. This is the main problem I will be addressing as my internship continues and my data is collected.