Page 20 - Curriculum Visions Dynamic Book

 The Shuttle trajectory. Notice the early release of the boosters and the late release of the external tank.
Four minutes and
30 seconds after takeoff the Shuttle can no longer return to the Kennedy Space Centre in case of an emergency.
Normal flight path
Orbiter and external tank separate
Six minutes after takeoff the Shuttle has already cleared the densest parts of the atmosphere and starts to turn into orbit.
By the time the solid fuel boosters have burned for
2 minutes, the Shuttle is at 44 km altitude, and they are then jettisoned. They do not fall immediately because they have enormous momentum, and so they continue to rise into the sky, reaching 65 km just over a minute later. Then they fall back, three parachutes opening to slow their fall. They land in the ocean and are recovered.
Orbiter
The orbiter has three engines with bell-shaped nozzles, each 2.5 m across and mounted on gimbAls. By turning the nozzles, the Shuttle can be steered. To make the combustion efficient, the propellAnts, in the ratio of six parts liquid oxygen to one part liquid hydrogen, are “preburned” before being fed into the combustion cHAmber.
When the main engines shut down, two orbital maneuvering system engines are ignited. They are on
pods close to the tail. They AccelerAte the Shuttle to
its final velocity of 7.74 km/s. These engines also act as retrorockets and can reduce the speed by 91 m/s. These engines use hypergolic nitrogen tetroxide and hydrazine propellants. They do not need a cAtAlyst igniter since they combust spontaneously on contact.
More precise maneuvers are made using the Shuttle reaction control system—38 small engines, of which 14 are at the front of the Shuttle and 12 on each rear pod. There are also six even smaller motors for fine-tuning controls.
Two minutes into launch, and the auxiliary boosters are released.
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