Component Parts Of A Jet Airliner And How It Functions
The airframe of the aeroplane is made up of thousands of precisely shaped, impact-resistant panels fastened to a lightweight underbase by rivets or other fasteners. Together, the frame and panels create a very sturdy yet reasonably light craft. While typical aluminium and aluminium alloys are also employed, carbon fibre reinforced material is used in many of these sections, particularly the exterior panels. The cross-sectional tube shape is supported by vertical frames that are joined from the nose to the tail by longerons. An extensive web of stringers, intercostals, and subframes lies between these.
The aircraft’s equipment bays, cargo compartments, and flying deck are among its pressurised sections. The tailcone, the centre wing box, the landing gear bays, and the radome are examples of unpressurized sections. The wings are attached close to the centre of the aircraft, and the fuselage and wing frames are connected by a centre wing box. To enclose and reinforce this crucial wing attach point, a wing-to-body fairing is attached to the keel beam and two external longerons. From the centre wing box to the tip of the wing, two flexible and sturdy spars run, one at the leading and one at the trailing edges. To support the jet engine, a pylon protrudes from the wing frame. From wing to pylon, titanium links are extended, and aluminium and titanium plates are mated by tension bolts to create an extraordinarily robust and flexible connection.
An auxiliary power unit (APU) is housed in the tailcone, and the plane’s vertical and horizontal stabilisers, with their supplementary frame supports, are located at the rear, or “aft”. Three layers of chemically toughened glass are assembled into windows, and each layer is coated with an anti-static substance. The thick outer pane of acrylic used in cabin windows helps to preserve the fuselage’s structural integrity. On the passenger side, there’s an extra layer of protection in the form of an acrylic pane that has an air gap and hole for temperature and pressure equalisation.
The aircraft’s lift is produced by its wings, and its primary flight control surfaces are the rudder, elevators, and ailerons. Generally speaking, the elevators control front to back pitch, while the ailerons work in opposition to each other to roll the aircraft. To maintain the plane at a specific attitude, the entire horizontal stabiliser can be moved, leaving the elevators for finer changes. These core systems are supported by secondary flight control surfaces.
During flight, the primary landing gear is tucked under the body and wing respectively. The gear is rotated into landing position by a hydraulic retraction actuator, and the revolving movement also causes the fairing doors to pivot. With an associated hydraulic shimmy damper to lessen shimmy or shaking that happens while under strong landing stresses, struts loaded with nitrogen and oil also serve as shock absorbers during landings. With rotors that match “keys” on the inside of the wheel to enable them to revolve together, each wheel has a powerful carbon brake stack.
A key element in the overall operation of the aeroplane is the jet engine. The thrust reverser assembly, which reduces wear on other landing components and enables shorter landing distances, is housed in it. It reverses fan thrust to slow the plane down after impact. The outside of the cowling is a translating sleeve that retracts rearward to block and reverse the typical thrust direction by bringing a ring of connected flaps into an inclined position.
An airport power supply is not yet connected to the aircraft, so the Auxiliary Power Unit (APU) serves as a backup power source for the cabin air conditioning, cockpit avionics, and other systems while the aircraft is grounded. Jet engines run on a fuel and airflow process that is started by the pressurised air from the APU turning a small turbine device at the engine, which in turn rotates the main gearbox and engine internals. Operating on similar principles as a jet engine’s core, the APU is essentially a gas generator.
A massive network of gasoline tanks makes up the plane’s fuel system, which is made up of the centre box and the majority of the interior wing surface. The left, centre, and right fuel tanks are the primary holding tanks, with a maximum capacity of 5,681 gallons (21,508 litres) each. With shutdown valves that automatically open and close to guarantee even filling, the wing-to-body fairing’s refuel/defuel panel manages the refuelling procedure. To lower the risk of a fire, regular air is substituted for nitrogen-rich air after refuelling.
Bleed air valves in the engine gather pressurised air for the crew and passenger compartments from the low and high pressure compressors within. Through ram air ducts in the wing-to-body fairing, this bleed air is cooled with outside air before entering the system. Additionally, a low pressure ground connection is provided so that an external air conditioning source can be connected while grounded.
Fog and anti-ice systems circulate melted ice through tiny exhaust slots at the bottom of the aircraft and use hot bleed air to pass through perforated piccolo tubes in the wing slats. A heating film is sandwiched between layers of glass on the cockpit’s side windows and windscreens.
The bottom of the aircraft has two electrical equipment bays: the mid equipment bay, located behind the wings, and the forward equipment bay, located behind the flight deck. The primary source of electricity is the generator that is affixed to every engine, with backup power coming from the APU. The high lift flight system, brakes, tyre pressure monitors, landing gear and other vital systems are all under the direction of three independent electrical power centres.
The aircraft is equipped with three independent hydraulic systems, one for redundancy and one for emergencies. System two has the same configuration on the starboard side as system one, with system one’s base parts found on the port side wing-to-body fairing. Rudder, elevators and spoilers are examples of vital flight control surfaces that are operated by hydraulic actuators. Aileron inboard actuators, left and right slat and flap brakes, left and right multifunction spoiler number 2, left and right elevator inboard actuators and the ram air turbine stow actuator can all be powered by emergency systems.
In addition to sinks at the forward and rear galley stations, the aircraft includes three bathrooms: one in the front, behind the flight deck, and two in the back. With heated water pipes and a heated blanket to prevent freezing, pumps draw water from a 42-gallon tank that is secured behind the back floor panels. Each washbasin has a water heater that heats the water and then uses a water mixer to control the temperature of the tap. The heated grey water drain masts located at the front and mid-rear of the aircraft’s underbelly are used to drain the grey water from sinks, and a waste tank is used to store and empty the black water from on-board toilets after landing.
Emergency equipment comprises first aid kits, flashlights, fire extinguishers, life jackets for the crew, megaphones, and portable oxygen cylinders that can supply oxygen to crew members for up to fifteen minutes. Every seat has an oxygen generator above it, and in the event that the cabin loses pressurisation, masks will pop out. In the event that a crash is detected, an emergency locator transmitter will automatically activate and send a signal that can be used to find the aircraft. When a passenger or service door is opened, an escape slide emerges from a dedicated compartment located close to the back of the wing, while door-mounted slides are crammed into a bottom compartment in each door.
When there is a complete loss of electrical power, a ram air turbine (RAT) immediately activates, producing emergency electricity by harnessing the motion of the aircraft through the air. This maintains the emergency and landing gear systems operational and powers the third emergency hydraulic system. There are temperature-sensitive fire detection loops surrounding every engine and the APU, smoke detectors in the cargo area and equipment bays and bathroom trash can fire extinguishers.
Together with an underwater location beacon that sends out a signal for ninety days, a flight data recorder tracks and stores the last fifty hours of operational data. An aircraft health management system keeps track of variables including gust, turbulence, and difficult landing situations in addition to storing maintenance data. Weather radar antennae are used for radio communication, collision avoidance, air traffic surveillance, GPS, and internet connection. Flood lamps are used for wing inspections, while navigation lights are used for aircraft visibility.