"But I thought you said that the fuel is corrosive, and couldn't sit in the engine for more than a few days without causing damage," readers angrily intone. "Get a job, hippie," is my reply.
It can't be possible that the North Koreans didn't know the limitations of their own fuel system, right? Surely. And yet the missile hit the Sea of Japan after just 35 seconds of flight-time in the first stage of the engine. Not only that, but apparently:
A separate report in the Mainichi Shimbun daily cited U.S. and Japanese government officials as saying a piece of the Taepodong-2 missile fell off immediately after take-off, strengthening the view that the launch was a failure.If a piece fell off immediately after take-off, then the launch was a failure from the first seconds - perhaps because the fuel had damaged essential components? Whenever you launch you learn something, but with so little controlled flight-time, they definitely didn't learn what they had hoped about more complex systems such as the multi-stage engine and ballistic targeting.
So, nicely done, North Koreans. You've really strengthened your hand with this one.