Re the multiple nuclear warheads that get loaded into ICBMs before launch. How dangerous are are they to be around re stray radioactivity coming off them?
[QThe answer is “not very.” The two fissile elements used in the construction of nuclear weapons are [sup]235[/sup]U and [sup]239[/sup]Pu, with half-lives of about 700 Myr and 24 Myr respectively, so the amount of radiation they put out is measurable but far plentiful. In addition, they’re both alpha emitters (helium atom) which is largely stopped by the exterior of the dermis. Unless these elements are injested, injected, or inhaled they are safe to handle with minimal protection. The weapon techs who handle the re-entry vehicles (the conical structure that houses the physics package, the trigger and permissable action links, and telemetry and post-release guidance system if it exists) don’t wear any special protection against radiation as the housing of the weapon itself provides adequate protection. The physics package itself comes “all-up”, in a sealed housing that is inserted into the RV, and is only opened at the factory maintenance facility, although boosted fission devices may have a external and field serviceable system for injecting tritium gas.
The biggest danger with handling older nuclear weapons isn’t the weapon material itself but the conventional explosives used to create the confinement to generate the conditions to force supercritical chain reactions. Many weapons used explosives (molded and machined from rigid “plastic” explosives with tolerances that would make a master machinist cry) that were sensitive to shock and electrostatic discharge, and many have an auto-ignition temperature that is below the nominal combustion temperature of the plastic binder, meaning that the explosive will probably detonate if it catches fire. In addition, some explosives will change and become more sensitive as they age, so stockpile maintenance involves what is called aging surveillance, in which samples of all critical materials are regularly evaluated for deviation from expected behavior. Handling of the physics package requires the same precautions as when handling the solid rocket motors that fly them, i.e. grounding straps, humidity and temperature control, et cetera. Since all of that handling is done inside indoor bays (and behind several layers of security) this isn’t generally a problem.
Modern weapons, like the W-87 (carried by the retired Peacekeeper and now the Minuteman III) and the W-88 (based on the D-5 ‘Trident 2’ SLBM) use what are known as insensitive high explosives (IHE) which are highly resistant to any normal shock or thermal environment, requiring a very high powered primary detonator to initiate detonation. There are additional failsafe devices on modern weapons that will prevent them from discharging without deliberate ignition.
Stranger
Having worked in the field years ago, I know that any detectable radiation above “ambient” was cause for “Broken- or Bent- Arrow” procedures. I assume that safety procedures and monitoring has improved over the last 30+ years, so I would suggest that if is detectable it isn’t a military grade weapon.
Stranger
Since this question seems to have been ansewered, if I might do a small hijack.
Did the soviets ever have the capability to determine the type of ICBM by the thermal plume if you will , more specifically could they tell if the rocket that was being launched was a minuteman or titan, or was it determined via geography. if the launch site was in North Dakota , it was probably a minuteman sorta thing.
Reason I ask , one of Clancys sequels to The Hunt for Red October, mentions secret launches out of vandenburg, which would be the SLBM’s that the fictional October would have carried. Since we let them know of test shot, would they be able to notice that the fictional SLBM was kinda familiar.
Declan
What you are talking about is plume phenomenology, or more specifically, the plume spectral signature. It is certainly possible to tell the difference between a liquid propellant rocket engine and a solid propellant rocket motor by the plume signature, as the solid rocket will have significantly lower temperature (~4100 K for a solid versus 6000 K for a liquid) and a higher molecular mass which means that all things being equal the plume will tend to spread a little less and will have less ideal gas behavior than a liquid. All ICBM/space launch class solid propellants also have a significant proportion of “solids loading” (granulated aluminum and iron oxides) which would stand out like a screaming child in a retirement community. You should also be able to discern between a cryogenic propellant rocket (LH[sub]2[/sub] and LOX) versus one that uses storable fuels and/or oxidizers (UDMH and IRFNA, or RP-1 and LOX) by the same methods, although the signatures won’t be quite as distinct. The LGM-25C ‘Titan II’ used Aerozine 50 and NiTet as fuel and oxidizer, while the various LGM-30 Minuteman family used an ammonium perchlorate oxidizer and aluminum fuelo with various binders, stabilizers, and energetic additives (basically explosives), so the two have very different plume signatures and performance characteristics. I’m not really knowledgeable about Soviet early launch detection systems but it would take only primitive spectrometry ability to discern between them.
Could you accurately tell one rocket from another, both using the same propellants, just from the plume signature? Probably not, or at least, not without a lot of characterization data. After all, if the fuels are the same, the products will be the same (or very nearly, depending on how complete the combustion and stoichiometric ratio is) and thus there will be nothing distinct about the molecular content and spectroscopic lines of the plume. One of the difficulties in developing detection capability for ABM systems is realistically testing them against representative threats that use propellants which the United States no longer uses because of safety and environmental restrictions.
However, there is more to the unique character of a rocket than just its plume. The real measure of rocket performance–and one that cannot be readily concealed, especially in a solid propellant or non-throttle-able liquid rocket–is its thrust profile and total impulse. These can be backed out (to a limited degree of precision) from the flight profile, and would at least tell you what class of rocket it is. You can perform energy wasting maneuvers (what we call generalized energy management sequence or GEMS) but these will show up as variation in plume orientation and oscillations in the vehicles forward acceleration and velocity, and also stress the structure of the rocket so it isn’t something you would do with a vehicle of unknown capability.
If I recall properly, the Krasniy Oktyabr was a modified Typhoon-class ballistic missile submarine. (I may be conflating the novel and the film, which had several differences and numerous technical errors on the part of the film.) The Typhoon class carried variations of the R-39 solid propellant SLBM (NATO reporting name SS-N-20 ‘Sturgeon’) which is roughly the same class as a UGM-133 ‘D-5 Trident II’ SLBM carried by the American Ohio and British Vanguard class boomers. I don’t know the specifics of solids loading on either booster, but it is entirely possible that the plumes would be similar enough to be indistinguishable from launch warning satellites; however, the D-5 was tested out at Cape Canaveral, not out of VAFB. More than likely, if the Americans wanted to test the motors in secret they would perform a serious of static fire tests, where the motor is erected onto a stand that measures the thrust and side forces and ignited. Although this would not give certain performance parameters like its responsiveness in flight, it should give enough information to accurately characterize the motor performance capabilities and frankly would probably be cheaper and safer than attempting flight testing.
Stranger