Seeing the flight process of the Nuri... "It turned off 46 seconds earlier than expected"

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Even if we look at the cases of advanced space countries so far, less than 30% of the cases in which the first launch was perfectly successful. Unfortunately, we also couldn't get over this wall because, as I said earlier, the three-stage projectile engine went out 46 seconds earlier than the target time.

Reporter Gu-Hee Jung will analyze and explain in detail the flight process of the Nuri.

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At 5 pm, the first stage engine ignites, and the Nuri goes up to the sky.

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 second-stage engine also raised the rocket to its target trajectory of 250 km altitude.

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

Having reached the target altitude, it can be evaluated that the first and second stages of the projectile and propulsion were sufficient, and the main engine technology, the core of the projectile, was sufficient.

The satellite has also been successfully detached, but this is where the problem arises.

The satellite was too slow to enter its intended 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 7-ton 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 300-ton and second-stage 75-ton engine technologies were secured, the combustion time problem of the third-stage engine I have a challenge to solve.