Why are aircraft runways so long? This is a question that many people ask. In airports around the world, we often see long runways, some of them over three or four kilometers long. These runways are designed and built to ensure the safety of flights taking off and landing.

The length of a runway is designed according to the distance required for an aircraft to take off or land. The distance an aircraft needs to travel from the time it begins to accelerate to the time it flies off the ground is known as the takeoff glide distance.

Similarly, the distance needed during landing is called the landing glide distance. To ensure safety, the runway length must exceed the distance required for takeoff and landing. In addition, the runway length usually exceeds the design requirement due to the safety margin required for the aircraft during takeoff and landing.

The design of runways takes into account many factors such as the aircraft type, weight, speed, altitude, and temperature. Runway surfaces are usually made of asphalt concrete or cement, with plastic runways becoming an increasingly popular option.

Runways require regular maintenance to ensure that the surface is smooth and free of cracks or other damage so that aircraft can take off and land safely. In winter, snow removal measures are required at airports in many countries to ensure that aircraft can take off and land smoothly.

In addition to runway length, there are many ancillary facilities that ensure safe takeoffs and landings. These include aircraft guidance lights, ground-based radar and radio equipment, aircraft navigation systems, aircraft speed indicators, and more.

All of these devices help pilots keep track of the aircraft in real time, thus reducing the risk of human error and accidents.

In addition to providing smooth flight paths for aircraft takeoffs and landings, runways also serve a number of other functions.

For example, in an emergency stop, the runway can help to slow down the aircraft and also ensure that the aircraft maintains a stable direction during the emergency stop, thus increasing safety.

The length of the runway is also used to calculate the performance of the aircraft for takeoff and landing. These performance parameters include factors such as takeoff and landing speeds, aircraft mass, and air temperature.

When flight planning, these parameters provide operators with the necessary information to help ensure safe and stable aircraft operations during takeoff and landing.

In addition to factors such as taxi distance, space, and facilities, the elevation of the runway is one of the factors that must be considered. Since the density of air decreases with increasing altitude, airports located at higher altitudes require longer runways to ensure safe takeoffs and landings.

In addition, factors such as temperature, humidity, and wind speed can also affect runway performance. These factors are collectively referred to as "flight considerations" and must be taken into account to ensure safe takeoffs and landings.

The reason runways are so long is that they are designed to provide a safe and smooth surface for aircraft takeoffs and landings.

The length of the runway is determined by the distance required for takeoff and landing, as well as the safety margin required for the aircraft during these critical stages of flight. The complexity and expense of building and maintaining runways make them an important factor in ensuring the safety of aircraft.