What is the significance of Max Q in rocket launches and disasters?

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SUMMARY

The significance of Max Q in rocket launches is critical, as it represents the point of maximum dynamic pressure experienced by a vehicle during ascent. In the case of the Space Shuttle, this pressure reached 720 pounds per square foot, equivalent to 5 psi, which is significantly lower than typical car tire pressure. The Challenger disaster highlighted the importance of managing forces at Max Q, as both the Shuttle's main engines and solid rockets operated at reduced thrust during this phase. Understanding Max Q is essential for rocket design and safety, particularly in relation to structural integrity and vibration management.

PREREQUISITES
  • Understanding of rocket propulsion systems
  • Familiarity with dynamic pressure concepts
  • Knowledge of structural engineering principles in aerospace
  • Awareness of historical rocket launch failures, specifically the Challenger disaster
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  • Research the engineering principles behind Max Q and its impact on rocket design
  • Study the dynamics of vibration during rocket launches
  • Learn about the Velocity Never Exceed (VNE) limits in aviation
  • Examine case studies of past rocket failures related to Max Q conditions
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Aerospace engineers, rocket scientists, safety analysts, and anyone involved in the design and analysis of launch vehicles will benefit from this discussion.

Devils
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So I was reading about the challenger disaster and came across this report:

http://history.nasa.gov/rogersrep/v1ch3.htm
Both the Shuttle main engines and the solid rockets operated at reduced thrust approaching and passing through the area of maximum dynamic pressure of 720 pounds per square foot.

I listed to rocket launches & they all seem to mention MaxQ but have never seen a value. From the report, 720 pounds per square foot = exactly 5psi. A typical car tyre is 30psi, so the maximum pressure on the space shuttle is about 1/6 of that of a car tyre.

That seems low to me so why mention it at all? The recent SpaceX was near Max Q so was that part of the problem, is was vibration the problem? What is Max Q for an airplane?
 
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I don't know what I'm talking about, but just from a quick glance, a tire is small and the pressure is distributed nice and evenly, over a smooth profile. And if you make the tire 2-5 times stronger than it needs to be, well no big deal. On a space shuttle with an (educated guess) frontal area of 80000 in^2, that 5psi adds up to 400,000 lbs of extra force, squeezing it lengthwise along uneven paths and who knows what, designed to be juuuust strong enough, in a complex machine with a small nuke's worth of explosives. That's definitely something that should be accounted for in the rocket's design.
 
I don't know what the maxQ of an aircraft is but pretty sure the VNE (Velocity Never Exceed) will be lower for a plane than a rocket perhaps by a factor of five?
 
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