Why does every space shuttle do a half turn after it has cleared the launch pad ?

Answer 1

The reason the Space Shuttle or Space Transportation System (STS) perfoms a roll has nothing to do with the external fuel tank being in the right position as another manouvre is perfomed to allow for this.

The Space Shuttle performs a roll to reduce stress on the wings and tail as air passing over these control surfaces approachs the speed of sound.

Answer 2

The space shuttle performs what is called a roll program whereby It spins through 90 degrees and rolls onto It's back. This heads It into the direction of the Earths rotation gaining It over 1000mph. The shuttle travels upside-down so that, in an emergency, the shuttle can separate and fall clear of the main fuel tank and the solid rocket boosters or SRB's, to hopefully make a safe landing.

Answer 3

It's to do with reducing the loss of accelleration due to gravity. If the shuttle is accellerating straight upwards, then it's having to fight against gravity to gain the height.

The turn allows the shuttle (and every other rocket for that matter) to accellerate more parallel to the earth's surface, and hence increase it's speed without fighting so much against the gravity.
If you think about it, the shuttle has to be moving completely parallel to the surface when in orbit. Otherwise, if it was just fired straight upwards, it would slow and then fall straight back down!

By turning in this way it can also make the best use of the solid rocket boosters, which provide the majority of takeoff thrust, but burn out more quickly than the main engines.

Incidentally it also takes the shuttle out over the Atlantic, and hence away from population centers in case anything goes wrong.

Answer 4

The Vehicles

An engineering concept shows NASA's new Cargo Launch Vehicle (Ares V) (left) and Crew Launch Vehicle (Ares I) (right)Ares V (CaLV)
Ares I (CLV)
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Ares V (CaLV) Flight Profile
Between T-10 seconds and T=0, five cryogenically-fueled RS-68 rocket engines located at the bottom of the Ares V core stage are ignited, similar to the fire-up sequence on the Space Shuttle. At T=0, the onboard computers, having verified that all five RS-68s are operating at full thrust and do not have any problems, will then light the two five-segment solid rocket boosters (SRBs). The Ares V will lift off from the launch pad, perform a roll maneuver to line up the booster on its preprogrammed flight trajectory and then pitch over to fly out over the Atlantic Ocean.

At an altitude of 60 km (200,000 ft.), the SRBs are jettisoned and fall back to Earth for a parachute recovery (they are later refurbished in Utah and reused as either a Ares V booster or Ares I first stage). At that point, the rocket, located above most of the atmosphere, jettisons the launch shroud to reveal the LSAM, which unlike the fragile Apollo Lunar Module, can withstand any outside pressures in the upper portions of the atmosphere. The RS-68s, powered at 100% rated thrust (during the first two minutes, the engines burn at 70% reduced thrust to reduce the effects of maximum aerodynamic pressure (Max Q) on the system), continues to power the core system until just a little over 8 minutes into the flight. At that time, MECO (main engine cut-off) occurs and the first stage is then jettisoned to burn up in the atmosphere over the Indian Ocean. The Earth Departure Stage, powered by two J-2X engines, then maneuvers the LSAM into a circular orbit which will then be retrieved by a separately-launched CEV within a month.

After the CEV docks with the LSAM/EDS, the EDS then fires its two J-2X motors again to thrust the CEV/LSAM stack towards the Moon. After shutdown, the EDS is jettisoned and goes into either a solar orbit or like the S-IVB stages from Apollos 13 to 17, can be deliberately crashed into the lunar surface to calibrate any future instruments left behind by the astronauts.

The Ares V can carry up to 125 tons into a 28-degree Low Earth Orbit, making it suitable for launching very large payloads like the Skylab Space Station, or up to 100 tons into an ISS-type orbit, making the Ares V a viable heavy-lift launcher for possible ISS modules and repair parts after the retirement of the Shuttle in 2010 (or after the ISS is retired in 2016, a replacement manned or unmanned microgravity station similar to the Mir space station). With a Centaur upper stage augmented with the EDS, it can launch heavyweight probes similar to the Galileo spacecraft or the Cassini-Huygens probe to Uranus, Neptune, Pluto, and objects in the Kuiper Belt and Oort Cloud using direct-flight trajectories with gravity assists with either Jupiter, Saturn, or both.

Answer 5

The shuttle does a roll to put it into proper position to jetison the external fuel tank should it be needed in order to make an emergancy landing if anything goes wrong.

Answer 6

I reckon it must be something to do with jettisoning the rocket boosters and main fuel tank. With the Shuttle upside down there is no danger of them hitting the craft when they are released.

Answer 7

When it turns, if you notice that it also becomes flying at an angle, and this is to help the shuttle "punch" through the Earth's outer atmosphere.

Answer 8

it takes a half turn because as it go upward the pressure will directly fall on thew chest n may damage the ribs, so as they take a half turn because the pressure will be less on the chest.i think so.

Answer 9

Because, otherwise, it will just go hit a hangar or control tower or something.

Answer 10

Maybe to stir up the liquid fuel in its tanks..but who knows ask NASA