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BicycleBill
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re: Severe vibrations likely brought down N. Korean rocket
BicycleBill   4/13/2012 8:50:22 PM
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Achieving an equatorial orbit from N Korea's latitude is difficult, see http://www.space.com/15228-north-korea-rocket-launch-complications.html as well as the comments to it for some insight.

prabhakar_deosthali
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re: Severe vibrations likely brought down N. Korean rocket
prabhakar_deosthali   4/14/2012 10:20:41 AM
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But as the report says they were trying to launch it in the polar orbit.

BrianFraser
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re: Severe vibrations likely brought down N. Korean rocket
BrianFraser   4/16/2012 5:52:08 AM
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They could bend it around to any orbit they wanted. See: "Responsive Coverage Using Propellantless Satellites", George E. Pollock, Joseph W. Gangestad, James M. Longuski, http://www.responsivespace.com/Papers/RS6/SESSIONS/SESSION%20II/2002_POLLOCK/2002P.pdf   Also: "New Synchronous Orbits Using the Geomagnetic Lorentz Force", Brett Streetman, Mason A. Peck (2007) http://www.spacecraftresearch.com/files/StreetmanPeck_JGCD2007.pdf

Sanjib.A
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re: Severe vibrations likely brought down N. Korean rocket
Sanjib.A   4/14/2012 9:33:07 AM
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Was this the first time that North Korea developed the third stage of rocket? If they have done this before then what might have gone wrong this time? Another question....is it the first time Iran and North Korea worked together?

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/16/2012 1:15:55 PM
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No, this was the third launch in the Unha series. The two previous launches also failed. For an analysis of NK-Iranian collaboration on multistage rockets, see: http://www.globalsecurity.org/wmd/world/dprk/td-2-3rd-flighttest.htm (I attempted to link to the above when I first posted the story, but the link, like the North Korean launch, failed during launch. It has been fixed in the story.)

sharps_eng
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re: Severe vibrations likely brought down N. Korean rocket
sharps_eng   4/14/2012 12:24:01 PM
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To me the most interesting question is, ' How do they know about the vibrations?'

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/16/2012 1:24:21 PM
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Max Q is well understood to occur at about 60 seconds after a launch. According to Western intelligence assets, the top of the rocket began to break up as the NK rocket passed through Max Q, even through the first (and probably second) stage continued to function as designed. Many of the Apollo astronauts commented on the intense vibrations during Saturn V launches. Alan Bean, the LM pilot on Apollo 12, said he was amazed at how bumpy the ride was: Do the engineers realize how this thing shakes, Bean recalled, because it shakes and vibrates so much more than I'd ever imagined. The difference of course is that the Saturn V held together every time. (Incidentally: Our source, Charles Vick, worked on the Saturn V program. He believes it should be taken out of mothballs and used again as the primary U.S. "heavy lifter.")

Brutus_II
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re: Severe vibrations likely brought down N. Korean rocket
Brutus_II   4/16/2012 10:59:51 PM
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When the space shuttle Challenger exploded in 1986, there was talk about bringing back the Saturn V for use as "the heavy lifter". One of the big issues with that was much of the tooling had been destroyed (on purpose), so it would have been like starting over from scratch. After all, it was only our tax dollars that paid for it all to begin with. Why not pay for it all again? I remember in the movie "The Right Stuff", John Glenn was freaking out over those vibrations. I thought his ship was just passing through the transonic range, but it must've been Max Q.

Duane Benson
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re: Severe vibrations likely brought down N. Korean rocket
Duane Benson   4/15/2012 6:48:24 PM
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It sounds to me like someone was just speculating on the cause. On the other hand, it's also possible that several governments as well as a few very talented amateurs managed to capture telemetry from the rocket and have done a preliminary analysis of that data.

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/18/2012 2:09:26 PM
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Duane, it is the latter. Charles Vick at GlobalSecurity.org has been tracking the North Korean, Iranian, Chinese and other rocket programs for years. He also closely tracks how scientists and engineers in each of these countries have worked together over the years to develop ballistic missiles, which appears to be the ultimate goal. Vick also is a veteran of the Saturn V program, the greatest rocket ever built and arguably the greatest machine ever built. Vick literally overwhelmed us with data and analysis when we spoke with him last Friday as more data on the NK launch was filtering in. It's good to know smart folks like Vick is tracking this stuff and can explain it all to journalists.

daleste
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re: Severe vibrations likely brought down N. Korean rocket
daleste   4/15/2012 7:52:10 PM
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Beside the political ramifications, it seems to me that North Korea would be better off expending their resources and energy in ways that would help their people and economy. But I guess dictators don't really care about the people.

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/16/2012 1:25:22 PM
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The Unha-3 launch alone was estimated to have cost Pyongyang $1 billion.

steve.freestone
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re: Severe vibrations likely brought down N. Korean rocket
steve.freestone   4/19/2012 4:55:36 PM
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You got that right.

Kinnar
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re: Severe vibrations likely brought down N. Korean rocket
Kinnar   4/16/2012 9:40:28 AM
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Designing the rockets are always critical task, there are too many sections working together that too for only one event. One this kind of event affects a lot to the development plans of a developing country like North Korea, lets hope they will come with a better applications in Space Technology.

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/16/2012 1:28:34 PM
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You are correct, kinnar. Multistage rockets are the ultimate systems integration problem. The NK and Iranian rocketeers should have known that their third stage was take the brunt of the resonance associated with entry into the period of maximum dynamic pressure (Max Q). The fact that their rocket couldn't withstand these vibrations indicates they are a long way from launching a ballistic missile.

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/16/2012 1:33:17 PM
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Note to fellow space enthusiasts: I expect to be near the end of the runway at Dulles International Airport on Tuesday (April 17) when the Smithsonian Air & Space Museum facility at Dulles, the Udvar-Hazy Center, takes possession of Shuttle Discovery. It's unclear whether I would be able to see Discovery and its 747 carrier during its final victory lap around Washington, DC, so the end of the runway is the next best place since the 747 carrier has to land sooner or later.

Robotics Developer
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re: Severe vibrations likely brought down N. Korean rocket
Robotics Developer   4/16/2012 5:17:59 PM
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I was relieved when the rocket launch failed to achieve orbit but saddened by the cost in money and to the people of North Korea. The estimated billion dollar price tag could have gone a long way to fixing infrastructure, improving life for all the N Koreans and was not a needed effort. I am sure that leaders of countries have different values and goals than mine so maybe this made sense to them, but I am at a loss to understand.

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/18/2012 2:10:38 PM
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We couldn't have stated it better, Robotics Developer.

ReneCardenas
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re: Severe vibrations likely brought down N. Korean rocket
ReneCardenas   4/16/2012 9:38:32 PM
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It is a shame that the populous are not able or willing to remove their miss-guided leaders. I wonder how long will their patience last, and realize that thier economy can withstand such waste. Would it have been cheaper to paid another country China, or perhaps even Rusia. To luch that satelite for them, if such was the REAL intent.

elPresidente
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Freelancer
re: Severe vibrations likely brought down N. Korean rocket
elPresidente   4/17/2012 2:15:04 AM
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The US need to keep shooting them down with the ABL, as they probably did in this instance. Don't kid yourselves - this is 1950's technology, not rocket science, in terms of getting it right in this day and age - kids are launching rockets in the desert that hit the edge of space. The idea of not having any kind of thrust governor via the turbopump sounds ludicrous, which also means the claims of a lack of a throttle is also silly propaganda. They are disadvantaged, not stupid.

Brutus_II
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re: Severe vibrations likely brought down N. Korean rocket
Brutus_II   4/17/2012 4:04:47 PM
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The fact that all the major governments involved, NK included, are not saying anything about the possibility of the missile being shot down speaks volumes. I wonder whether the remnants of the rocket have already been recovered from the ocean floor and by whom. If it was indeed "disabled" in flight, it would be best to get a hold of it so there's no evidence of "a mysterious blast hole" in the rocket's body somewhere. Now that would be an interesting front page image to see (possibly with very bad repercussions).

george.leopold
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re: Severe vibrations likely brought down N. Korean rocket
george.leopold   4/18/2012 2:12:43 PM
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Vick noted that some missile sections landed in waters off the S. Korean coast. He thinks Seoul will definitely attempt to retrieve these parts.

KB3001
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re: Severe vibrations likely brought down N. Korean rocket
KB3001   4/17/2012 7:45:13 PM
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I lean towards this view too.

old account Frank Eory
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re: Severe vibrations likely brought down N. Korean rocket
old account Frank Eory   4/18/2012 11:10:53 PM
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I see your point, but just because NK had another rocket failure doesn't mean somebody shot it down. It's quite an exaggeration to say kids are launching rockets that hit the edge of space. It wasn't until 2004 that serious amateur rocketeers (adult engineers with money to spend) crossed the 100 km altitude -- the official edge of outer space -- and there were many failed attempts prior to that. I agree, the North Koreans are not stupid, but they are in fact inexperienced. The fact that this rocket design has failed 3 times just makes NK like everybody else who has tried to reach orbit. And like everyone else, if they keep trying, learning and making adjustments, it is likely they will eventually succeed.

ocm9057
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re: Severe vibrations likely brought down N. Korean rocket
ocm9057   4/17/2012 2:26:01 PM
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...heard Visiontech was their main supplier

mfm0411
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re: Severe vibrations likely brought down N. Korean rocket
mfm0411   4/18/2012 10:43:46 AM
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Great opportunity for a directed energy weapon. I wonder.

t.alex
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re: Severe vibrations likely brought down N. Korean rocket
t.alex   4/18/2012 9:46:38 PM
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Interesting if we can have some teardowns pictures ;-)

R G.Neale
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re: Severe vibrations likely brought down N. Korean rocket
R G.Neale   4/18/2012 10:21:52 PM
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Do any of our expert contributors know the type of guidance system that the N Korean rocket used, was it a launch-and-leave inertial navigation system or was it under guidance control via radio links from the ground? If it was the latter then it would be relatively easy for the guidance to be interfered with (i.e.hacked)by a third party and course changes made that would introduce destructive vibrations. It is even possible and ground controlled local area self destruct switch was left open and accessed. There would be more evidence of that.

steve.freestone
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re: Severe vibrations likely brought down N. Korean rocket
steve.freestone   4/19/2012 5:01:03 PM
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Vibration tore the thing apart? Reminds me of a motorcycle I used to own.

DrQuine
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CEO
re: Severe vibrations likely brought down N. Korean rocket
DrQuine   4/21/2012 2:53:16 PM
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The law of unintended consequences: the more rocket launches fail and the more the west critiques their technology, the more driven the North Koreans are to continue their efforts with funds that would be much better devoted to humanitarian objectives. Now it becomes an ego issue. If only we could have ignored the entire venture. After the first or second launch, the North Koreans could have moved into another venture with better public relations potential.

zeeglen
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re: Severe vibrations likely brought down N. Korean rocket
zeeglen   4/22/2012 6:39:42 AM
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good, Good, GOOD Vibrations. The Beach Boys got it right...



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