An aircraft in flight is the center of a continuous tug of war between four forces: lift, gravity force or weight, thrust, and drag. In order for an aircraft to fly straight and level, the relationships of the four forces are Thrust = Drag and Lift = Weight.
Lift: the force which opposes the force of gravity (or weight).
Gravity: the natural force of attraction exerted by a celestial body upon objects at or near its surface, tending to draw them toward the center of the body.
Thrust: a force created by a power source which gives an aircraft forward motion.
Drag: the force which delays or slows the forward movement of an aircraft through the air when the airflow direction is opposite to the direction of motion of the aircraft.
An aircraft's ability to fly depends upon the speed of the air passing its wings, called its airspeed. The faster the wings move through the air, the greater the lifting force. Flying into the wind causes the wings to move through the air more quickly without increasing the speed of the aircraft in relation to the ground. This means that an aircraft flying into the wing can get into the air more quickly, without moving as fast in relation to the runway. This then reduces the fuel consumption and extends the lifespan of the engine. Landing into the wind also means that the aircraft can land more slowly in relation to the ground.
In addition, landing and taking off into the wind increases the stability and operability of the aircraft which then makes it safer to fly. Today, as technology becomes more advanced, the speed and the stability of an aircraft has been greatly enhanced. The impact that the wind direction has on aircraft landing and take-off is gradually reduced.
The window shutter must be opened so as to allow passengers to take note of any abnormal occurrence outside the aircraft. Passengers can then inform the cabin crew in a timely manner. When an emergency takes place, it also allows the search and rescue people from outside the aircraft to observe the situation inside the cabin.
The formation of contrails is a natural phenomenon. Contrails are also called vapor trails which are long, thin artificial clouds that sometimes form behind aircraft. Their formation is most often triggered by the water vapor in the exhaust of aircraft engines, but can also be triggered by changes in air pressure in wingtip vortices or in the air over the entire wing surface.
The cabin lights are switched off so that your eyes are adjusted to light conditions in case of emergency when lights are cut out. The first few seconds required for your eyes to get adjusted to the darkness, are the most vital in life saving. The lights in the cabin are therefore dimmed in order that your eyes are adjusted to darkness.
Jet A1 is the most commonly used fuel for commercial aviation, which is produced to a standardized international specification. It is similar to the kerosene used for home by nature. Jet A1 is different from the other fuels, e.g. gasoline, in that it does not release flammable substance. Jet A1 will not burn if it is not heated or atomized.
The largest fixed-wing aircraft ever built in the world is Antonov An-225 Mriya (Dream)NATO reporting name: Cossack.It is the greatest and heaviest load-lifting aircraft commercially available for flying any over-sized payload due to the unique size of its cargo deck. An-225’s operating empty weight is 285,000kg. It is 84m long with maximum flying speed at 850km/h (460knots, 530mph).
A double-deck, wide-body, four-engine aircraft Airbus A380 is the largest passenger aircraft in the world. Airbus A380’s operating empty weight is 276,800kg. It is 73m long with maximum flying speed at 1,020km/h (551knots, 634mph). It provides seating for 525 people in a typical three-class configuration or up to 853 people in all economy class configurations.
BD-5 is the smallest aircraft in the world. BD-5 is162 kg in weight, 3.7 m long, has a wingspan from 4.26 m to 6.55 m (depending on used modification), and can fly at 483 km/h (300 mph). It has a small fuselage, small engine installed in a compartment, and small propeller (or jet engine in the BD-5J variant) in the rear.
Air traffic controllers coordinate the movements of aircraft, keep them at safe distances from each other, direct them during takeoff and landing from airports, direct them around bad weather and ensure that traffic flows smoothly with minimal delays.