Understanding the basics of aerodynamics is critical to understanding rocket flight. The Terran Space Academy helps you understand the science behind aerospace vehicles like the SpaceX Starship and the Virgin Galactic SpaceShip Two. Starting with aerodynamic forces like Lift, Weight, Thrust and Drag, then progressing to an understanding of transonic flight, aerodynamic pressure and MaxQ.
...Lift induced drag helps keep an airplane in the air by supporting its weight,
While vortex drag can create a pocket of negative pressure above the wing
to help pull it up into the air.
These forces effect rockets also,
Rockets have to turn horizontally to get enough speed,
relative to the planet,
to achieve orbital velocity,
and their entire structure works like a wing during passage through the air.
As they start to turn air is compressed under the ship providing lift
and vortices and other effects can create an area of low pressure above the ship,
The lift generated helps fight the force of gravity pulling it back down.

This horizontal turn is called a pitch-over maneuver.
This has to be done before the rocket is going too fast or the forces generated can tear the rocket apart. The engines gimbal and the rocket starts to turn,
controlled by the inertial guidance system,
as you see here.
After the rocket turns a few degrees to tens of degrees,
depending on the design of the rocket,
the engine gimbals back to neutral again,
pointing straight down the axis of the rocket.
Gravity will now try to turn the flightpath back toward the ground on its own,
slowly turning the rocket more and more horizontally as the rocket continues to speed up.
If the rocket lost power, it would fly in an ellipse and hit the ground.
(It’s only an arc if you don’t make it.)
By the time the rocket is in level flight relative to the Earth’s surface
it is above almost all of the atmosphere.
and traveling fast enough that the path of its fall.
coincides with the curve of the Earth.
It constantly falls but never hits.
This is the definition of freefall.
With a multistage rocket engineers may design a little coast time after first stage separation
before the second stage fires
to allow the rocket to naturally complete more of this pitch over.
This works well for rockets launched in a thick atmosphere.
like Earth or Titan
reducing aerodynamic drag and stress.
The second stage fires when the rocket is closer to horizontal.
and does not have to burn fuel making this maneuver.
None of this applies to launching from the Moon or any other extremely low atmosphere place like Deimos or Mercury, you go up high enough that you’ll have enough time.
To go horizontal and achieve orbital velocity before you fall back to the surface.
You would need a pitch over maneuver, but there would be no lift or drag to help…
Music Credits


Ambiment - The Ambient by Kevin MacLeod is licensed under a Creative Commons Attribution 4.0 license. [ Ссылка ]
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The Rising by Aakash Gandhi

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