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Cubesat Launch Ends in Failure

Change writes "The CalPoly Cubesat group's launch yesterday has been a failure. It seems the first stage did not separate from the Dnepr rocket properly, and the vehicle crashed about 25km south of the launch site. More will be known when the debris is recovered and analyzed. A second launch is still in the works, but the loss of the 14 satellites from this launch is an unfortunate end to quite a lot of hard work of many engineering students."

6 of 122 comments (clear)

  1. Russian luanch failure rate? by MrTester · · Score: 2, Interesting

    Anyone know what the Russian launch failure rate is over the last 5 years?
    Its got to be pretty damned high.

  2. Re:Old Ballistic missile was used... by Guysmiley777 · · Score: 4, Interesting

    Doesn't make me wonder. The Minuteman III and Polaris missiles have solid boosters with "end the world by" dates. Once a booster is expired, they either test fire it (sans warheads) or scrap it. The warheads can be reused on a fresh new booster.

    --
    Coding with assembly is like playing with Legos. Coding an application in assembly is like building a car with Legos.
  3. Shouldn't happen more than once. by pontifier · · Score: 5, Interesting

    It seems like every time a rocket blows up or fails to launch the payload is lost. Why? It keeps happening, and the payloads keep being destroyed. Failsafes to prevent this need to be in place. I envision a payload pod with tripple redundant explosive release mechanisms, and capable of re-entering the atmosphere from orbit. I'd love to just once hear: "rocket blows up, payload recovered, re-launch expected after payload is tested and re-certified."

    --
    -John Fenley
    1. Re:Shouldn't happen more than once. by theycallmeB · · Score: 2, Interesting

      Except for the 'rocket blows up' part, it has happened. Twice.

      In 1984, two communications satellites that had been left in low parking orbits after booster failures were recovered during a Space Shuttle mission (STS-51A). However, after the Challenger accident the Space Shuttle was permanently taken out of the commerical satellite launch and recovery business for fairly obvious reasons. The reason you don't hear about payloads recovered from the failure of single use launchers is that it would cost far more to install a recovery system than it does to buy insurance.

  4. Re:Old Ballistic missile was used... by lelitsch · · Score: 2, Interesting

    The solid booster ones should be in reasonable shape, but the Dnjepr is based on the SS-18--a liquid propelled rocket. And yes, given the usual quality of Soviet manufacturing, I do wonder how many of the SS-18 would actually go boom. After all, since they probably only flight tested a few percent of the total production, anyone who took a few shortcuts on the assembly line was probalby reasonably safe. That's unlike satellite launching systems where pretty much every rocket ever assembled will be fired at one point or another.

    I don't know about the USSR first hand, but in Eastern Germany it was very common to assemble some percentage of the production very carefully (public demonstrations, testing, the one the party leaders get delivered) and do a very slipshot job on the rest.

  5. Re:Old Ballistic missile was used... by dougman · · Score: 4, Interesting
    I'm assuming you're just kidding, at least about the US arsenal. This is something that is taken very seriously. Confidence in the performance of weapons is managed through stockpile surveillance, assessment and certification, and refurbishment.

    Contrary to popular belief (and Hollywood movies) one doesn't just drop a nuclear warhead or "blow it up" and get a mushroom cloud. Thinking about these sorts of problems has been going on since at least 1960. Read up on the NIKE system (no, not the shoes) for a bit of history on air defense guided missile systems.

    An exceprt on the guidance system:

    The computer command circuits initiate detonation of the warhead by sending a burst command to the missile by the way of the missile tracking radar system. Upon receipt of the burst command, the command detonation control circuits activate the warhead detonation devices. In a surface-to-surface mission, the burst command does not detonate the warhead. Instead, the burst command arms the barometric fuze, which detonates the warhead at preset altitude above the target, and disables the fail-safe circuits. The fail-safe control circuits operate if ground guidance ceases or if a malfunction occurs within the missile. Should either condition prevail for approximately 2 seconds, causing interruption of the hold-off pulses from the transmitting circuits, the fail-safe circuits cause automatic destruction of the missile.

    There are numerous layers of logic like this that are designed just for the issue you bring up. Clearly an ICBM should have enough smarts to know that it hasn't left reached it's target if it is only 20 yards from the launch site and the onboard altimiter never reached a height of over 200 feet.

    Take a look at those links. I think you'll find the history of these systems very interesting. Since some of the technology is rather old, it is somewhat easier to understand (think of modifying a transistor radio versus an iPod full of SMT parts).