On what basis is the aircraft fuselage designed? Can it be in a square shape or maybe a rectangle? Think about it.
Airplanes are transportation devices which are designed to move people and cargo from one place to another. Airplanes come in many different shapes and sizes depending on the mission of the aircraft.
The fuselage, or body of the airplane, is a long hollow tube which holds all the pieces of an airplane together. The fuselage is hollow to reduce weight. As with most other parts of the airplane, the shape of the fuselage is normally determined by the mission of the aircraft.
A supersonic fighter plane has a very slender, streamlined fuselage to reduce the drag associated with high speed flight. An airliner has a wider fuselage to carry the maximum number of passengers. On an airliner, the pilots sit in a cockpit at the front of the fuselage. Passengers and cargo are carried in the mid and rear of the fuselage, and the fuel is usually stored in the wings. For a fighter plane, the cockpit is normally on top of the fuselage, weapons are carried on the wings, and the engines and fuel are placed at the rear of the fuselage.
There are several types of doors that may be considered, which are installed at the main body, the nose, or the tail of the airplane, which again depend on the requirements.
The weight of an aircraft is distributed all along the aircraft. The fuselage, along with the passengers and cargo, contribute a significant portion of the weight of an aircraft. The centre of gravity of the aircraft is the average location of the weight and it is usually located inside the fuselage. In flight, the aircraft rotates around the centre of gravity because of torques generated by the elevator, rudder, and ailerons. The fuselage must be designed with enough strength to withstand these torques
Pressurised aircrafts always tend to have the circular cross section, simply because it’s the most effective shape that can hold pressures. But then again, not all airplanes are pressurised, and other requirements might be leading, such as comfort of passenger.
When designing the cargo deck of the fuselage, designers often use the standard container sizes that are widely used by airports all over the world. They are called LD’s (load devices). These containers are standardised because it is convenient with respect to the airport luggage transport and management
As a rule of thumb it is said that, if the number of passengers > 150, then install 2 aisles if the number of passengers > 500, then consider 2 decks.
An increase of 10% in the diameter yields a 2% in drag increase.