NationStates Jolt Archive

The Bladerunner torpedo is the prized secret weapon of the Griffincrest Security Naval Forces. Used to great affect against GASN and anti-CA fleets in two wars, it has come time to explain just exactly what this torpedo is.

The Bladerunner torpedo is developed to be able to be either launched from a GNF vessel, primarily a stealth ship, or else dropped from specialized Hong-5 bombers. The Bladerunner has two engines, a primary and secondary. The primary engine is designed to carry the weapon a maximum of 10 km at speeds at its fastest record 100 knots. This is not recomended, and usual speed is around 70 knots.

The primary engine, secondary engine, and saws are all powered by a powerful gas turbine, which runs off Griffincrest gas of course.

Once the Bladerunner makes impact with a ship, the first meter and a half will crush inwards, than shatter off to the sides, thus exposing a pair of Zirconia saws. ("Zirconia cutting blades, for example, last 90 times longer than steel blades. In addition, zirconia cutting blades have very sharp edges and resist corrosion and oxidation especially in harsh environments " http://www.ultrahardmaterials.co.uk/CeTZPvsSteels.html)

After the initial impact, the power is transferred from the engines to the saws, and a much weaker engine is brought online, propelling the torpedo at 10 knots or less as it cuts its way through the hull of the enemy ship. Should the saws for some reason be unable to penetrate the hostile vessels armour (ex. the saws dull or torpedo malfunctions) the weapon will detonate its payload right then and there. However, if it is able to succeed in its original mission, the weapon will follow a pre-determined course programmed before launch. Once the destination, usually in the center of the ship, is reached, the weapon will detonate. In smaller vessels, this should be enough to crack them in half.

OOC: Go on, time to bitch.

You're not going to get a hundred kilometers at one hundred knots, that's five times the range of modern torpedoes at two thirds the speed. You also aren't going to be able to fit such a torpedo on a Hong-5. World's fastest non-supercavitating torpedo is the Spearfish, 81 knots known max speed and a range of ~23,000 yards at 60 knots. Source (http://navweaps.com/Weapons/WTBR_PostWWII.htm). It weighs 1,850 kilograms. Max payload for a Hong-5 is 3,000kg. Building a much larger torpedo with two sets of engines, saws, a lot more fuel, and an indeterminate payload is going to more than double that weight.

There's no point to the saws. An under the keel detonation, something we've been doing reliably since WWII, is far more effective and snaps ships in half anyhow. The Aussies have a nice slideshow here showing how that works. (http://www.navy.gov.au/weapons/torpedoes.html)

You've made no provision for guidance. Your two main options, since this is against surface ships, are wake-homing (wake-nibbling being a tougher to achieve derivative) and passive sonar. Active sonar gets cluttered up by the surface, doesn't work against surface vessels. The problem is that both of these (and active homing for that matter) are limited in their aquisition ranges. Numbers I've seen for modern torpedoes are ~4,000 yards. That means that you'll need to accurately inertially guide your torpedo to within 4,000 yards of where the ship will be. Exceedingly difficult task at that range, since guidance probably won't be accurate enough for that and you'll need to predict the ship's future movement (ie, where it will be by the time the torpedo gets there). Furthermore, at the speeds you are talking about, passive sonar will almost certainly be rendered useless by self-noise and the noise of its own travel.

The Bladerunner is actually lighter than most other torpedoes, because the first meter and a half is empty. The explosive is 100 pounds of HMX, a very highly explosive material. The Bladerunner is electric powered, and run off a battery in the torpedo, and thus carries no fuel. The British torpedo was, according to your link, developed in 1978. In NS, the Confederacy, and Griffincrest, are in the year 2015, thus giving us a good thirty something years to get a faster weapon, longer ranged weapon. As we have learned over the past thirty years, weapons can go a long way in that time, look at the F-22 Raptor or B-2 Spirit.

Saws are way cooler

And for guidance it uses GPS/LIDAR.

Nope the saws are totally useless, you would get much better performance out of a similar weight of explosives.
Using a battery is a bit useless aswell, they tried that but it turns out that batteries are a lot bulkier and heavier than a decent fuel powered motor and simply don't provide enough power.

The speed issue is not really a case of "oh i stick in a mad power engine", 80knts is likely about the limit of what can be achieved without having to resort to some sort of super cavitating system. I would also point out that the 80knot version of spearfish does not date from 1978, it dates from 1994.

GPS giudance is likely of limited untility unless you expect the topedo to run on the surface or trail a long antenna behind it. GPS giudance also faces the same issues as a decent inertial navigation system in that they can have issues unless you have some means of providing mid course giudance updates to respeond to target manouvers, this would be important for a 25nm torpedo so it will be absolutly vital for a 100nm version.
While iIam far from an expert on LIDAR i would doubt that it would give you a terminal homing range greater than a decent passive sonar.

The Bladerunner is actually lighter than most other torpedoes, because the first meter and a half is empty.

Doesn't matter if the first meter and a half is empty. You still need to accomplish certain things, all of which require weight. Furthermore, that meter and a half is going to do induce severe bouyancy and depth keeping problems.


The explosive is 100 pounds of HMX, a very highly explosive material.

So you have about as much HE as a Mark 50 Barracuda, the range of which is probably simila tor, or a little better, than the Mark 46 (both of these are light weight torpedoes) which has a range of 8,000 yards. The Mark 50 has half the speed that you're claiming. Both of these torpedoes are anti-submarine torpedoes, with minimal anti-shipping value. Sheesh, you've got less than a quarter of the warhead weight of a Harpoon, and you're expecting to snap ships in half?


The Bladerunner is electric powered, and run off a battery in the torpedo, and thus carries no fuel.

So you're using an energy source that is far heavier for the same amount of propulsive power? You're going to weigh even more than I suggested. Furthermore, you're not going to get that speed with an electrical battery. Simply doesn't happen. There's a reason that the Spearfish uses a gas turbine engine.


The British torpedo was, according to your link, developed in 1978. In NS, the Confederacy, and Griffincrest, are in the year 2015, thus giving us a good thirty something years to get a faster weapon, longer ranged weapon.

Well that's great. But you need to explain how you do it, not just magically say "I have it!" So far all your explanations have failed.


And for guidance it uses GPS/LIDAR.

That satisfies the inertial guidance (though only until someone does something smart and knocks out your GPS system, or jams the signal). However, you still have the problem of knowing where they will be. Like Crookfur said, LIDAR won't give you all that much better range, and it won't allow the nifty things you can do with passive sonars (homing in on a particular engine) or wake-homing (being undecoyable).

stealth ships and torpedos with saws ...... sounds awfully familiar? lol


*hums 007 theme*


you just need to fix some of the technical kinks in it and it would be a great weapon.

this is going to be useless against anything bigger than a light cruiser. because most large combat ships in NS have armor thick enough and tough enough that the teeth on your saw will have worn down to stubs by the time they get half way through. against super dreadnoughts (which is what your useing them against in the Ryu no Shogun War thread) they have no chance the armor on a SD is so thick that a plasma cutting torch is going to have extreme difficulty getting through

Well, Mistal, Rosdivan, and Strath stoled my points.

why dontcha just cruise missile the target? isn't that simpler?

why dontcha just cruise missile the target? isn't that simpler?

cause this was cooler

Ok, so lets say I cut down the range by alot, like down to ten miles, will that work? The biggest problem I've heard is range.

And the torpedo is supposed to go along the water, like only a few inches beneath the surface.

cause this was cooler

Ok, so lets say I cut down the range by alot, like down to ten miles, will that work? The biggest problem I've heard is range.

That'll work. Still a dumb idea imho, and you're going to need a gas turbine for that speed.

That'll work. Still a dumb idea imho, and you're going to need a gas turbine for that speed.

Meh, I like it, and I'll install a gas engine than too, thanks Ros.

Btw, what is imho

And the torpedo is supposed to go along the water, like only a few inches beneath the surface.

It's liable to breach the surface and destroy itself then, you'll need it at least 20 feet deep.

Meh, I like it, and I'll install a gas engine than too, thanks Ros.

Btw, what is imho

In my humble opinion.

Personally I think that, even though it is a cool idea, you are better off using conventional torpedoes..But that's just my ,2c..I'm not one to stop others from using their defense budget in such..Interesting ways.

It's liable to breach the surface and destroy itself then, you'll need it at least 20 feet deep.

I don't doubt you, but can you explain why?

I don't doubt you, but can you explain why?

It is too close to the surface. If it isn't predicting wave action precisely, it'll be too high, and come out of the water when the wave causes a dip, leading to it slamming into the water again at 100 knots. Torpedoes don't usually come out on the winning side of that.

It is too close to the surface. If it isn't predicting wave action precisely, it'll be too high, and come out of the water when the wave causes a dip, leading to it slamming into the water again at 100 knots. Torpedoes don't usually come out on the winning side of that.

Good point, okay, it will go deeper than too, thanks

Your blade will fracture upon impact...

Zicronia only has a fracture toughness of 10.1, while Stainless steel has a Fracture toughness of 100... Pressure vessel is perhaps the best on the chart your first post linked me to.

(best Hardness and frature resistance, and highest tensile strength)

But eh, what do I know when I work with metals almost daily?

Ceramics may be hard, but they shatter real easy... And it'll shatter whenever you hit your target 'wrong', which will almost always happen unless done with double decimal precision in millimeters...