The hurdles that face a spacecraft during its launching

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Spacecraft endure significant stresses during launch, including intense inertial forces and vibrations that can shake the vehicle. Differential forces affect larger crafts, necessitating mechanical isolation for sensitive components like crew capsules. Acoustic noise and vibration profiles vary by launch vehicle, impacting payload integrity. Historical examples, such as the Apollo 13 mission, highlight issues like pogo oscillations that can lead to engine shutdowns to prevent damage. Understanding these pre-orbital stresses is crucial for spacecraft design and mission success.
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Hello,
My question is quite simple.
What kind of abuses does a spacecraft sustain from the moment it's launched until it's placed on orbit?I've always heard of what a spacecraft must face in the spatial environment but I've never heard of what it must face before it gets to it.
Thank you.
 
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There are huge inertial forces affecting a craft during launch - which shakes the crap out of it. A large craft is affected by differential forces across the length of the vehicle. The 'passenger' capsule is usually mechanically isolated from the launch vehicle for this reason.
 
Cerdocyon said:
Hello,
My question is quite simple.
What kind of abuses does a spacecraft sustain from the moment it's launched until it's placed on orbit?I've always heard of what a spacecraft must face in the spatial environment but I've never heard of what it must face before it gets to it.
Thank you.

One of the astronauts said it was like being on the end of a whip antenna. The craft is built lightly and is flexible.
 
Different launch vehicles have acoustic noise and vibration profiles that the payload (say, a satellite or crew capsule) has to endure during launch. As an example, you can look at the Falcon 9 Payload User's Guide [1] or the Atlas V User's Guide [2]. If you want to dig up some more profiles yourself, a search for "acoustic noise and vibration of launch vehicles" [3] may give you some ideas of what is involved.

[1] http://www.spacex.com/Falcon9UsersGuide_2009.pdf
[2] http://www.ulalaunch.com/site/docs/product_cards/guides/AtlasVUsersGuide2010.pdf
[3] http://www.google.dk/search?q=acoustic+noise+vibration+launch+vehicle
 
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Ok thank you for your answers, it helped me a lot.
 
Something interesting to note is that the center engine on the Saturn V rocket was subject to such violent oscillations that it actually had to turn itself off on the Apollo 13 launch to avoid tearing apart the launch vehicle.

The mission was launched at the planned time, 02:13:00 PM EST (19:13:00 UTC) on April 11. An anomaly occurred when the second-stage, center (inboard) engine shut down about two minutes early. The four outboard engines and the third-stage engine burned longer to compensate, and the vehicle achieved very close to the planned circular 100 nautical miles (190 km) parking orbit, followed by a normal translunar injection about two hours later.[8][5] The engine shutdown was determined to be caused by severe pogo oscillations measured at a strength of 68 g and a frequency of 16 hertz, flexing the thrust frame by 3 inches (76 mm). The vehicle's guidance system shut the engine down in response to sensed thrust chamber pressure fluctuations. Pogo oscillations had been seen on previous Titan rockets, and also on the Saturn V during Apollo 6,[9] but on Apollo 13 they were amplified by an unexpected interaction with turbopump cavitation.[10] Later missions implemented anti-pogo modifications that had been under development. These included addition of a helium gas reservoir to the center engine liquid oxygen line to dampen pressure oscillations, an automatic cutoff as a backup, and simplification of the propellant valves of all five second-stage engines.
http://en.wikipedia.org/wiki/Apollo_13#Launch_and_translunar_injection
 
Huh, knew it had lost an engine, never heard why before, thanks.
 

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