Question

how physics different and same for commercial planes,private jets ,private propellor planes

Answer 1

Jets versus Planes :

Jet aircraft have several distinct advantages over traditional propeller planes. The largest of these advantages is that jets can travel much faster than propeller planes, up to and beyond the speed of sound.

Jets can also travel at higher altitudes due to the specific needs of their propulsion systems. Propellers require dense air to engage the spinning blades, whereas jets employ turbochargers to compress even the thin air that exists in the stratosphere until it is suitable for combustion in the jet engine. Flying higher allows planes to avoid turbulence that occurs at lower altitudes and also increases the number of aircraft in the skies since they can operate at different altitudes.

Development of Jet Planes :

Jet-powered aircraft have existed as experimental models or designs on paper since the earliest days of aviation. British and German engineers turned more attention to the development of jet aircraft following World War I, when aviation had proven so vital.

The onset of the second World War galvanized these efforts. The first practical plane fully powered by jet engines was the German Heinkel He 178 in 1939. Meanwhile, the first Italian-designed jet, the Campini N.1, took its first flight in 1940, and the British Gloster E.28/39 took test runs in 1941. The United States entered the jet race with its Bell XP-59 in 1942.

Jet planes were too late to prove effective in World War II, where propeller planes still dominated, but jets were important to the Korean War and all wars thereafter. Commercial jet service began in the early 1950s, and today jets dominate the majority of medium- and long-distance flights around the world.

Propeller Planes :

Despite the popularity of jet planes, propeller planes still serve important roles. Most major airlines use propeller planes for short regional flights since they are less expensive to maintain and operate. Declining revenues during challenging economic times prompted cancellation of jet service to many smaller airports, and in some cases, propeller plane service filled the gap.

This, however, represents a challenge to airlines who must combat a negative public view of propeller planes. Passengers complain about the turbulence and noise of propeller planes as well as the perceived lack of safety and slower speed of travel. Still, their small size and lower fuel consumption make propeller planes a vital part of operations for airlines struggling to lower their costs while maintaining a broad service network.

How Do Planes Fly: Thrust and Drag :

Drop a stone into the ocean and it will sink into the deep. Chuck a stone off the side of a mountain and it will plummet as well. Sure, steel ships can float and even very heavy airplanes can fly, but to achieve flight, you have to exploit the four basic aerodynamic forces: lift, weight, thrust and drag. You can think of them as four arms holding the plane in the air, each pushing from a different direction.

First, let's examine thrust and drag. Thrust, whether caused by a propeller or a jet engine, is the aerodynamic force that pushes or pulls the airplane forward through space. The opposing aerodynamic force is drag, or the friction that resists the motion of an object moving through a fluid (or immobile in a moving fluid, as occurs when you fly a kite).

If you stick your hand out of a car window while moving, you'll experience a very simple demonstration of drag at work. The amount of drag that your hand creates depends on a few factors, such as the size of your hand, the speed of the car and the density of the air. If you were to slow down, you would notice that the drag on your hand would decrease.

We see another example of drag reduction when we watch downhill skiers in the Olympics. Whenever they get the chance, they'll squeeze down into a tight crouch. By making themselves "smaller," they decrease the drag they create, which allows them to zip faster down the hill.

A passenger jet always retracts its landing gear after takeoff for a similar reason: to reduce drag. Just like the downhill skier, the pilot wants to make the aircraft as small as possible. The amount of drag produced by the landing gear of a jet is so great that, at cruising speeds, the gear would be ripped right off the plane.

For flight to take place, thrust must be equal to or greater than the drag. If, for any reason, the amount of drag becomes larger than the amount of thrust, the plane will slow down. If the thrust is increased so that it's greater than the drag, the plane will speed up.