Jump to content

Kryten

Members
  • Posts

    5,249
  • Joined

  • Last visited

Posts posted by Kryten

  1. 1 hour ago, DerekL1963 said:

    There appears to have been a problem.   The announced range is inconsistent with [short of] the range shown in a propaganda picture showing Kim Jong-un observing a map of the planned trajectory.

    Burn time was shorter than the successful may test, so seems to have been an engine failure. Exactly how much shorter is not really established, but probably 10 seconds or so given trajectory.

  2. On 8/25/2017 at 11:46 PM, sevenperforce said:

    http://thebulletin.org/north-korea’s-“not-quite”-icbm-can’t-hit-lower-48-states11012

    Interesting. According to this assessment, which seems pretty detailed, NK's new ICBMs don't have enough dV to reach the continental United States, and may not even be able to hit Alaska.

    Evidently, the lofted trajectory we saw would only have been possible with almost no payload; the off-the-shelf Russian engines NK has stockpiled don't have enough thrust to get the demonstrated trajectory unless the rocket itself is fairly small, which in turn means the payload is much lower than the 500-600 kg they'd need to field a warhead. [snip]

    The analysis is based on questionable assumptions. This article goes through better than I could.

  3. Most modern fairings have a rounded 'ogival' fairing, it's just a lot of rockets use old designs. The atlas 5 pointed fairing is a direct descendent of the original atlas-centaur fairing from the 60s, and the DIVH fairing was designed for Titan IV in the eighties.

  4.  Solid fuel needs to be under pressure to burn quickly and completely enough to be useful propellant; that's part of why their dry mass is so high, the casing needs to contain that pressure. If you end up with any holes, and it would be very difficult to avoid them in a situation like this, you're not going to have a useful engine anymore. If you do manage to avoid holes, you've just reinvented the casing.

  5. http://allthingsnuclear.org/dwright/new-north-korean-icbm 

    This launch demonstrated enough range to probably hit New York, and maybe hit DC.

    8 minutes ago, sevenperforce said:

    No knowledge yet as to whether they've improved their re-entry capabilities.

    The re-entry was successful. We know because it was close enough to the Japanese coast that people saw it; http://www3.nhk.or.jp/news/special/northkorea_provocation/

    (RVs tend to be very bright upon re-entry, so it's probably not as close as it looks.)

  6. 1 hour ago, CatastrophicFailure said:

    ..yet they remain confident enough in the second launch that it's got a paying customer (ArabSat 6). :D

    Arabsat-6A isn't your average payload either, it cost somewhere in the region of $300 million: about twice as much as Amos-6. There could be quite a kerfuffle should it end up in the Atlantic.

  7. They make shiny mockups, take money from rubes, and occasionally launch solid fireworks. A big liquid propellant rocket, even monoprop, is vastly outside their realm of expertise.

    EDIT: They just put up a post on facebook saying their stock price is likely to rise, but cannot fall regardless of the launch outcome. That's the kind of people we're dealing with. I'm not even sure they can legally say that, they certainly couldn't in this country.

  8. 11 minutes ago, Racescort666 said:

    Which makes teargas an interesting choice for police departments considering it would be a form of chemical weapon, banned under the Geneva Protocol, but common practice to use on civilians. /offtopic

    The Geneva convention only covers warfare. Tear gases are considered CW and banned in military contexts.

  9. 40 minutes ago, Streetwind said:

    They actually developed both, and keep carrying along both to this day. Which is also a part why Tory Bruno is anxious to make a selection soon. He wants to be able to cancel one of the two. While it's only a partial cost increase, not a straight doubling, it's still an unnecessary expense.

    The CDR assumed the methalox version. The kerolox is in dev, to an extent, but it's clearly getting nowhere near the resources of the methalox version. Hell, have ULA even released an official image of the kerolox version?

×
×
  • Create New...