Airplane flight is a delicate balance of physical forces. Pilots are trained to recognize the importance of gravity and speed in relation to the quality of different levels of the atmosphere. Essentially, it is a good idea to understand the different stages of flight and how physics affects them differently.
Achieving Flight in an Airplane
In order to actually get the airplane off the ground, engineers who build airplanes and the pilots who fly them must understand the physical principles relating to air pressure displacement. They use these principles in addition to building the aircraft with specialized aerospace fittings in order to fly. By manipulating the movement of air, the airplane can take off from the ground and stay aloft. This is accomplished through speeding down the runway before takeoff, which makes air move quickly over the wings. A quick upward tilt of the nose of the craft helps to swiftly move even more air against the wings of the airplane, which lifts the body into the air by displacing the air pressure.
Maintaining Flight in an Airplane
When the airplane is finally in the air, pilots have to ensure that the engines are running appropriately in order to keep moving. With constant speed from the engines, pressure can be maintained to keep the aircraft in the atmosphere. Through experience, pilots and aerospace engineers have discovered that 35,000-40,000 feet is the ideal height above sea level for airplanes to fly in balance with natural forces. One of the most important things that pilots watch for while operating aircraft is optimal fuel usage at a proper height. If the plane runs out of fuel prematurely, the pilot will not be able to maintain the balance of air pressure correctly and may need to make an emergency landing to refuel the plane and check the engines.