Rocket Launch - Orbital Launches

Orbital Launches

Orbital launch vehicles take off vertically, and then begin to progressively lean over, usually following a gravity turn trajectory.

Once above the majority of the atmosphere the vehicle then angles the rocket jet, pointing it largely horizontally but somewhat downwards, this permits the vehicle to gain and then maintain altitude while increasing horizontal speed. As the speed grows the vehicle will become more and more horizontal until at orbital speed, the engine will cut off.

All current vehicles will stage- jettison hardware on the way to orbit.

When launching a spacecraft to orbit, a "dogleg" is a guided, powered turn during ascent phase that causes a rocket's flight path to deviate from a "straight" path. A dogleg is necessary if the desired launch azimuth, to reach a desired orbital inclination, would take the ground track over land (or over a populated area, e.g. Russia usually does launch over land, but over unpopulated areas), or if the rocket is trying to reach an orbital plane that does not reach the latitude of the launch site. Doglegs are undesirable due to extra onboard fuel required, causing heavier load, and a reduction of vehicle performance.

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