Artificial satellite refers to an unmanned spacecraft that orbits the earth in space orbit (at least one circle). At present, the number of satellite launches accounts for more than 90% of the total number of spacecraft launches.
The final flight phase is the general acceleration phase and the final flight phase of the launch vehicle.
Launch
First, when the launch vehicle with satellite stands on the launch pad, all preparations are completed, and the final preparatory stage is entered according to the "countdown procedure". With the launch command of the ground control center: "9 8. 7．6、5. 4、3. 2、1 . After launch, the first stage rocket engine is ignited, and the carrier rocket begins to rise off the launch pad, and the speed is faster and faster. This is the beginning of the acceleration flight segment.
Accelerated flight segment
The launch phase is the period from the launch of the launch vehicle from the ground to the delivery of the payload into the predetermined orbit. The route traveled at this stage is called the launch orbit. After 10 seconds to 0 seconds after the launch vehicle takes off vertically, it starts to turn slowly according to the predetermined procedure. After the engine continues to work for more than 100 seconds, the launch vehicle has risen to an altitude of about 70 kilometers. When it basically reaches the required orbital speed and the direction close to the ground, the first stage rocket engine is shut down and separated. At the same time, the second stage rocket engine is ignited and continues to accelerate.
At this time, it has flown for 2-3 minutes, and the altitude has reached 150 km-200 km. It has basically flown out of the dense atmosphere. Throw off the arrow fairing according to the predetermined procedure. Then, when the rocket reaches the predetermined speed and altitude, the second stage rocket engine is shut down and separated, and the acceleration flight phase ends.
Inertial flight segment
At this time, the launch vehicle has gained a lot of kinetic energy. Under the action of the earth's gravity, it begins to enter the inertial flight phase until it is tangent to the predetermined orbit of the satellite. The third stage rocket engine starts to ignite and enters the final acceleration phase.
Final acceleration section
When it accelerates to a predetermined speed, the third stage rocket engine shuts down, and the satellite ejects from the rocket carrier and enters the predetermined satellite orbit.
So far, the mission of the launch vehicle has been completed.