There is a certain circle of people who are fond of aviation. But some are just interested in airplanes in principle. For someone else, aircraft speed is of particular interest. But before you determine this value, you need to know that this speed is divided into true, instrumental and ground.
When each type of speed is considered separately, the instrumental (either indicator, or IAS) is usually called “speed along the wide arrow”. In the past, pilots used scarves to fly. With their help, the speed was determined based on how strongly this scarf developed during the flight in a stream of air that flowed around the open cabin.
Undoubtedly, such a measuring device could not give out any digital value, but then there was no need for this. Much more important was the determination of the power of the air flow and whether it would be possible to lean on it, while eliminating the risk of falling into a tailspin.
This device was subsequently called the instrumental speed of the aircraft or pressure head. At present, this is determined by a tube brought out of the plane. The air flow that enters it deflects the arrow of the device itself, thereby indicating the instrument speed.
In addition, it is worth considering that when raised to a height, the density of air gradually decreases , and in near space this figure is zero. Therefore, it is important to know that, maintaining a certain instrumental (constant!) Speed during the climb, at certain altitudes the speed of the aircraft can almost double.
At the same time, the performance of the device will remain unchanged, because there are much fewer molecules at a height, which means that there are fewer molecules in comparison with how many there are directly above the ground. From this it turns out that there are two aircraft speeds - instrument and true.
Unlike the instrument one, the true one (it is also called “speed along the narrow arrow”) is not used for piloting, but mainly for navigation. This is due to the fact that when there is no wind, there are no problems, and if there is one, the speed of the aircraft will change in one way or another (either decrease or increase).
Ground speed was previously calculated by dividing the distance that the aircraft traveled by time. But the emergence of new inertial Doppler systems and GPS made it possible to determine this value by other methods, each of which is unique.
Just before takeoff, each aircraft has zero speed. But the speed of the aircraft during take-off for each type of this transport has its own. And it depends on certain conditions: take-off mass, air temperature, altitude of the airfield above sea level and some others.
So, heavy civilian aircraft have an indicator ranging from 200 to 250 km / h, medium - from 150 to 180, and military - from 250 to 300 km / h. But from year to year on new types of aircraft, these speeds are reduced due to the fact that the design of various elements of a given vehicle is constantly improving (engine power, wing mechanization).
The speed record was set in 2007. This value was according to the latest data 300 km / h. And the maximum speed of the aircraft today can reach more than 850 km / h. In this case, the take-off speed should be at least 150 km / h.
A passenger plane must take off at a speed of about 300 km / h to take off. It follows that the average speed for air transport should be approximately 200 km / h.
Today there is such a plane, the name of which is supersonic. Its distinguishing feature is that the speed of this transport in air exceeds the speed of sound.