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It's not a rude thing to do, but even countries ahead of us succeed in the first launch in about 30% of cases.

Today (the 21st) almost broke the 30% wall, but the third stage engine was turned off a little early, so the final stage could not be completed.



Reporter Jung Gu-hee reports.



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At 5 pm, the 'Nuriho' rises to the sky as a spark is ignited in the first stage engine.



Lake Nuri soars stably without shaking, and the speed gradually increases.



Less than a minute after launch, now only flames are visible from afar.



Two minutes after launch, the first stage of the Nuri-ho is separated by spitting out flames and falling into the sea is captured.



The first stage, a 300-ton engine, raised the Nuri to the target orbit of 59 km.



After disappearing from view, the two-stage engine also raised the rocket to its target trajectory at an altitude of 250 km.



Over the next 10 minutes, the Nuri gained speed and reached its target point of 700 km altitude.



It can be evaluated that the first and second stages of the projectile had sufficient propulsion, and the main engine technology, which is the core of the projectile, was sufficient for climbing to the target altitude.




The satellites have also been successfully separated, but this is where the problem arises.



The satellite was too slow to enter its target orbit.



The satellite had to enter at a speed of 7.5 km/s to orbit the Earth, but the speed fell short of the target.



The 7-ton 3-speed engine at the top of the Nuri was the problem.



The three-speed engine is the engine that delivers propulsion to the very end.



It was supposed to burn for 521 seconds, but it went out earlier than expected.



[Lim Hye-sook/Minister of Science and Technology Information and Communication: It did not reach the target speed of 7.5 km/s, so it could not land in low-Earth orbit.

This is because the 7t liquid engine installed in the 3rd stage did not burn for the targeted 521 seconds and ended prematurely in 475 seconds.] Although the



first stage 300t class and second stage 75t class engine technology was secured, the combustion time problem of the 3rd stage engine I have a challenge to solve.



(Video Edit: Kim Jong-mi)



▶ 'Meaningful failure' The task to be solved before the second launch of the Nuri-ho is


▶ "It was too cool to be a failure"...

Nuriho re-attempts with regret