OK, so I’m weak on the physics of ballistics and missile guidance.
So can someone answer me this...
Isn’t a rocket launch and guidance based on science on mathematics? If so, shouldn’t the launch be nothing more than what the engineers have proved and re-proved time and time again in working out all the various scenarios? How can these engineers have a launch that fails (short of the obvious variables like mechanical breakdown, etc.).
I don’t understand why the NoKos can’t do this successfully, unless their engineering is hopelessly flawed, in which case they shouldn’t be staging these pie-in-our-own-face circuses.
consider that we with all our expertise and that of the German rocket scientists, we still had years of failures
in our programs. its math/science/engineering/program management, and being able to learn from failure.
they also need for there to be freedom to bring bad news
to the attention of management.
Some things are just difficult. You can't simulate everything (such as the effects of vibration, thermal shock loads, timing issues on separation, etc.). The US had a couple of dozen failures in our early rocket program. Remember Vanguard?
The joke was that Vanguard was like a government worker: 'You can't fire it and you can't make it work.'
A liquid fueled rocket is best described as a "controlled explosion". There is a very fine line between controlled and uncontrolled however. A missile is a very complex machine with thousands of parts. A failure of any one part can compromise it's flight. The more parts there are the more things that can go wrong. Modern missiles are designed with the absolute minimum of parts since any redundancy would increase weight and lead to more complexity, both undesirable traits. I am surprised that the North Koreans have not transitioned to solid fuel rockets as Iran has done. The difference being the elimination of much of the failure prone machinery used to move the fuel and oxidizer from storage tanks to the engine.
US missiles (except cruse missiles) whether land or underwater based, are all solid fueled. Solid fueled rockets are as dependable as a rifle cartridge, light the fire and it goes every time. The only advantage that liquid fuel has over solid is the ability to vary the thrust in flight which is not worth the complexity. If you want to shorten the range of a given solid fueled missile you could program the guidance system to track a steeper ballistic trajectory rather than vary the thrust.
Regards,
GtG