5 thoughts on “Down In Flames”

  1. But this broad technical and political support for the shoot-down was hardly mentioned in the days and weeks that followed

    Sure, why let facts get in the way of a good story.

    So what if they did have other reasons for shooting it down the way they did? That might just be a bonus. The navy did a heck of a job.

    In my experience a large percentage of justification comes after a decision for action is made, but in this case it seems they were concerned over mitigation of a hazard. Absurd speculation by the press is not such a bad thing except when it becomes predominate.

  2. Since I was messing around with a nearly identical problem… I applied the Orion reentry profile to a 2cm thick Ti tank with hydrazine. In order for the hydrazine to NOT reach its auto ignition temperature (260C, and this is in contact with glass for Ti it’s much lower) The tank or any connecting lines will combust if exposed to 100s of air flow. In other words the spacecraft protects the tank for up to 400 s of reentry. I don’t believe it; honeycomb Al with graphite face sheets would come apart within seconds. I took into account latent heat of melting and vaporization, which is much lower than water.

    Having said that I can imagine ways that the tank could have stayed intact, it’s just unlikely. Rationalizing the shoot down on the hydrazine alone just perpetuates our ultra risk adverse space program and society in general. I was/am fully supportive of the shoot down for other reasons and had even proposed it 2 years earlier.

    BTW The Higggins guy arguing against the tank being destroyed makes the following incorrect, even ridiculous statement.

    “If an explosion of the hydrazine vapor had occurred, the tank and the condensed hydrazine inside would have survived. Such tanks are rated to hold tens of atmospheres of pressure, while an explosion of hydrazine vapor at these pressures would not have exceeded an atmosphere of overpressure.”

    Low pressure propellant (Hydrazine) tanks are rated at 250 psi. High pressure Helium is usually used as a pressurant. Those tanks are rated at 6000+psi.

  3. The satellite “shoot down” was a clear message to foreign powers *cough* China *cough*.

    Any of the stated justifications are lacy concealment of the real facts.

  4. Oberg offers no new technical analysis here.

    The NASA study that he quotes shows that the tank would have ablated — ignoring the fact that the hydrazine would have also reached its auto-ignition temperature.

    What are Oberg’s qualifications anyway?

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