Retired army generals: Spend Trident money on the army

@AC (Reply to JonB)

>>Actually, the US have several layers of veto on Trident, from the hardware, through the software and on upwards. For example, the system simply will not accept an independant attack plan (ie, one adopted by NATO, which means one adopted by the US) and even if such a plan could be forced into the system, the hardware can be locked by the Pentagon at any time. In practise, the system is probably always locked with a special clause to allow test firings, which it is capable of distinguishing. That's all I know about but since the source code for the software is not shared with the UK, there could be absolutely anything else in there too.<<

This doesn't sound likely to me and I wrote some of the software that went on Trident boats. Admittedly, my involvement was with the Navigation subsystem, so I have no expertise regarding the fire control system, but my experience did give me some insight into just how isolated a ballistic missile submarine on patrol is for most of the time. The reason boomers (as they were nicknamed) make for such good deterrent systems is that they are hard to find. The reason they are hard to find is that the ocean is rather opaque to most of the electromagnetic spectrum. This opacity has downsides as well as advantages, in order to communicate by radio a sub either has to get close to the surface and trail a long antenna behind it (and get lousy bandwidth) or else actually stick a mast up above the surface of the water (and chance giving away its position). Otherwise, the sub is essentially incommunicado for the balance of its patrol. This being the case, just how could the hardware "be locked by the Pentagon at any time"?.

As far as not accepting an "independant [sic] attack plan", I suspect that what you have as an "attack plan" at fire control is the coordinates of the targets (longitude, latitude, perhaps altitude and vertical deflection: longitude, latitude, and vertical deflection is the info that the nav system is responsible for providing to fire control about the point of launch, so I assume that similar info is needed about the points of impact). On what basis a computer could discern an independent attack plan from the above is beyond me.

It seems to me that you not only have a rather paranoid view of the US but a remarkably low opinion of the Royal Navy in that you think that they would be willing to spend vast sums of money on a deterrent system that is so hobbled that it is inherently incapable of performing its role (a deterrent weapon that one can't actually shoot isn't a deterrent, its a bluff).

Better spent than welfare

I would prefer my tax money spent on this rather than paying a fortune to the unemployable lazy population (single parents etc) we seem to have to drag along with us. Amazes me we spend more on these people every year than on investment in infrastructure and military that lasts 20 years. No wonder we are now a second rate nation.

@AC (US involvement/"missile numbers")

Here is where my involvement with the Navigation subsystem bears more directly: you don't need GPS to fire a missile. The boat's position sent to fire control is based on an inertial navigator. Initially this was SINS (Ships Inertial Nav System) but was later supplanted by ESGN (Electromagnetically Supported Gyro Navigator). Now error pileup in the inertial navigator would require you to do an update from an external fix source every [classified], but while this fix source *could* be GPS, it didn't *have* to be: you could head towards an area where the bottom of the ocean was well mapped and do a sonar fix or do a LORAN (LOng Range Aid to Navigation) fix (this was the area I spent the bulk of my time on). There also used to be a NAVSAT (Transit Satellite) fix source, but this was replaced by GPS.

Now it is possible that the Trident missiles use GPS for in flight corrections, but I would be surprised indeed if the missile couldn't also a celestial navigation backup, should GPS be unavailable or, if all else fails, just depend on the inertial navigator in the missile. At worst what you would be looking at would be degraded accuracy, but when you are talking strategic nuclear weapons you only need to be but so accurate.

Also, your yield numbers for the Trident missiles are way off. The standard warheads are all sub-megaton in yield, less than half a MT in fact (Google W 87 or W 88). The Wikipedia article on the UK Trident suggests that it uses warheads based on the older W 76 design, which had a still lower yield.

So many scenarios....

I rather liked Lewis' article on the many fantasies that would make an SSBN really useful, they are however fevered speculation to try and prove a weak point. I mean, would France really not be bothered by a nuclear strike on a country 30 miles away as Lewis suggests? And who is the mystery nation with nuclear weapons and ICBMs who is out to get us? Given that the UK is part of NATO and the EU and ideologically aligned to most of the members of the groups which nation would single us out for a nuclear strike ignoring our many allies?

The counter argument tends to run "You never know what might happen in the future, so lets tool up" This arguement is as pointless as it sounds. If you can't divine the future what makes you think sub launched nuclear weapons are a solution? Perhaps the next threat to humanity is an epidemic, bet you'd wish you'd spent those billions on improving hospitals and science education (which would have a benefit anyway unlike an unused SSBN).

Also @bazza, India first tested in 1974 and Pakistan 10ish years later, that didn't stop them fighting directly or indirectly much of the time since. In fact nuclear armed countries seem to get into wars as often as non nuclear ones do. What's the point of a deterent that doesn't actually deter aggressors? I notice Gen. Galtieri didn't seem bothered by the nuclear deterent and his troops had to be removed from the Falklands the traditional way.

Maybe we could spend the Trident replacement money on some of those Chinooks Lewis seems so keen on?

@Greg Trocchia

>This being the case, just how could the hardware "be locked by the Pentagon at any time"?.

I think AC is saying that it's locked all the time, and only unlocked for test firings.

Probably the biggest issue with a broken system is that we might find out, in which case

the US's strongest ally and a useful second vote in the security council becomes rather hostile.

An independent British missile system actually strengthens theirs as well, an attacker can't assume that an attack on the US that stops the US threat won't be responded to by a British system.

A useless British system would compromise any strategy toward an enemy that presumably knows that it's useless, since AC's posting in the register know this then it's safe to say the rest of the world does as well.

Clearly the US could sneak in code that prevents UK Trident from working, the question I suppose is have they? Given the total destruction of their international relations it would cause, an awkward legal case when Britain tries to get a refund, and the subsequent doubt cast on their own deterrent it's probably more in their interests to hand over a working system.

Yes, they could shaft it with GPS, but it'd still get close enough.

BTW The Vanguard class carry 16 missiles each of which can have up to 8 warheads. In practice there won't be 8 warheads on a missile, since the MIRV footprint is only about the size of the UK limiting the number of different targets one can hit with one missile, besides you might not want to use 8 warheads at once so a spread of loadings will be on the boats.

I still reckon it should be dumped, we could get an airborne capability in a couple of years and with the new euro-cruise coming along that could carry warheads for comfortable distance, enough to put off anyone who cares from trying.

@Greg Trocchia : GPS

GlobalSecurity.org claims that Trident uses star sighting to navigate the MIRV at least, GPS appears to be a retro fit, Trident itself being based on tech that pre-dates GPS by quite a while.

How they know such things isn't revealed however.

@peter

>if ( md5( fire_plan.coordinates + pentagon_secret_key ) != fire_plan.checksum ) printf( "bog off\n" );

First up, MD5 is insecure, I'd expect GCHQ to be able to bodge it.

Secondly this would require an interface to enter the "pentagon secret key" which might give the game away.