Who needs tanks?

[BMR]

Originally Posted by Ulzgoroth

If the gun is braced in line with your body, you can't aim it at a target without exposing the applicable body part. If you're firing the gun at a significant offset from your center of mass, torque issues apply.

Agreed. Therefore, some sort of projectile diverter will be needed in conjunction with the camera, mirror, or scope.

The Germans built corner pipes with mirrors attached so their MP43/StG44 carbines could hose those darn Russkies off of their tanks. They also built special mounts and periscopes for their MG42 machine guns which allowed the gunner to be completely concealed and beneath the weapon.

With beam weapons or magnetic launchers, some sort of magnetic or gravity device would be required to curve the projectile around cover. Lasers could also use mirrors or prisms, so long as these things don't rapidly melt.

[Ulzgoroth]

Originally Posted by BMR

Agreed. Therefore, some sort of projectile diverter will be needed in conjunction with the camera, mirror, or scope.

The Germans built corner pipes with mirrors attached so their MP43/StG44 carbines could hose those darn Russkies off of their tanks. They also built special mounts and periscopes for their MG42 machine guns which allowed the gunner to be completely concealed and beneath the weapon.

With beam weapons or magnetic launchers, some sort of magnetic or gravity device would be required to curve the projectile around cover. Lasers could also use mirrors or prisms, so long as these things don't rapidly melt.

I don't know if you want to do that.

You have the exact same torque issue as if you hadn't attached the diverter. Plus diverters went out of style for good reasons, I think. Though for beam weapons, they'd be more workable.

What a diverter would let you do is support a massive weapon that you couldn't support on the end of the arm, and hide the weapon itself from enemy fire. Maybe good if you've got a huge laser cannon built into your hull. It doesn't help with the arm's-length recoil issue, so if you want to mount a 120mm cannon you probably might as well put it on a stalk.

[BMR]

Originally Posted by Ulzgoroth

What a diverter would let you do is support a massive weapon that you couldn't support on the end of the arm, and hide the weapon itself from enemy fire. Maybe good if you've got a huge laser cannon built into your hull. It doesn't help with the arm's-length recoil issue, so if you want to mount a 120mm cannon you probably might as well put it on a stalk.

This is pretty much what I considered for warships a few years ago, when I was trying to apply my Navy experience to speculative fiction.

It occured to me that a weapon fixed inside of the hull would be harder to target and disable than a turret, could be cheaper to build and mantain, and could deliver more firepower. Because you knock out all the mechanics of traverse and elevation, your weapon is simpler and has fewer points of failure. The Navy already applies this principle to most (but not all) of our guided missile launchers.

Beam weapons and guns, however, still have to aim their projectiles. I figured that a coilgun or laser weapon could use some sort of muzzle diverter. The weapon itself would be countersunk into the hull, so it would have some angle of fire and the diverters would be partly shielded. Gun pores, so to speak.

Practically speaking, however, America's enemies seldom have the skill or wherewithal to target a weapon. Mostly, trained warriors of any branch just go for center of mass, and that includes ship-to-ship combat.

Part of this is technical limitaton--many fire control systems are only sophisticated enough to hit the center of the radar contact. Part of it is operator training and skill, which tends to be poorer than the public or politicians are led to believe. Part of it is target layout--an enemy fire control radar may be mounted in a different postion from the weapon.

A lot of it is projectile quality--American torpedoes in World War II were often duds, and they lacked the more advanced targeting systems of late-war German torpedoes. Many of the anti-ship missiles used by today's rivals also tend to dud; they kill because the rocket motor is still pumping fuel and fumes into the space. Well into the 1980's, active-homing ASMs could be confused by rain or dense fog.

Thus, when specific points are targeted, it tends to be broad: the engine section and the superstructure.

With lasers and coilguns using "fly-by-wire" magnets or prisms that provide second-by-second corrections for pitch, roll, wind, temperature, course, and speed, fire control could be more accurate. But China, India, Iran, and Russia aren't going to be mounting these sort of things anytime soon, let alone lesser rivals or terrorists.

The foes we face the most are suicide boats disguised as civilian commerical vessels. Gunboats and missile boats are also another common threat. These guys aren't going to be hitting our turrets. So the question of any fixed weapon able to "fire around corners" becomes one of cost. Is it cheaper and easier to maintain, but just as accurate and devastating?

[blacksmith]

Originally Posted by Fred Brackin

Any hover "tank" requires recoilless weapons to avoid zooming about like an air hockey puck when firing their main weapon. Use of recoilless weapons does away with most of your point about arms v. turrets.

Not really. The recoil argument sure, but not the weapon size argument. Arguing about recoil of course depends very much on your tech assumptions, laser type weapons are unlikely to have serious recoil.

The dubious vehicles in Hammers Slammers require cinematically effective hover capability as well. Those metal skirts they use are simply silly.

Sure, but so are mecha.

[blacksmith]

Originally Posted by Agramer

Who needs tanks?

Well they will have defensive measures devised even if infantry can penetrate their DR.Maybe expected lifetime of MBTs on battlefield will be shorter but they are essential for offensive actions.

This has been said for 50 years. Rather like the idea that all air to air combat will be with missles it doesn't seem to be happening.

Also youd need something extra heavy to smash through fortifications.

Unless you have personal weapons that can smash through any fortification
this is the Starship Troopers assumption

Where are Mechas in that picture:

I see them in very specialised and/or very generalized rolles.

Lets not forget we already have The Mule!

or Toyota model

or Land Walker

So with improvements in their "walking ability" they could become real asset in heavy terrain(woodlands,swamps,jungles,heavy mountain...) where classic vehicles cant go.

Small ones could be used as support for Spec op teams,expendable antiarmour roles.

Multi-purpose units with detachable sockets for engineering,cargo dealing...to weapon platforms.

They wont be able to go toe to toe with MBTs,but there are many tactical situations where they can be really useful in different sizes.Though if you introduce Antigravity superscience than Mechas become obsolete.

So I really wouldnt put question in line of MBT or Mecha but rather Where can they supplement each other or What purpose can they fulfil that other cant.

Note that Mecha here generaly means humanoid walker, not any walker.

[Langy]

Found some down time here.
Thank you for laying out your assumptions.
TL 10 ETK - This doesn't look all that bad. Converting the TL 9 100mm canon to ETK at 2x conventional you get 6d x 37. I am sure that I forgot some TL upgrade in there but it isn't as fierce as the 6dx50 with a kinetic kill missile or 1050 pts of damage.

The Ogre book specs Ogres with between 3000 and 18,000 DR. In converting to 4e will that go up or down some? UT gives a max of 700 DR to a, presumably, MBT grav tank.

So it looks like we need to finalize your armor assumptions. What do you want for armor and how much is too much for the vehicles to move?

Converting the TL9 100mm cannon to ETK gives you 6dx50 damage by itself - the 100mm cannon does 6dx25 damage and you multiply that by two to get the ETK damage. If you use boosted velocity mode in your ETK gun, you get a further +1 damage per die or +300 damage. That's 1350 damage on average, or 6dx64 pi++ damage.

Still not enough to pierce an Ogre's armor until you add an armor piercing warhead onto it - you can boost that 6dx64 pi++ damage to 6dx64 (5) pi++, which will penetrate up to 6,750 DR on average.

Also, the tank in Ultra-Tech isn't a main battle tank. It's a light tank with about half the armor (and mass) of a TL8 main battle tank. It's specifically called a Light Battle Tank in the book.

[Anthony]

Originally Posted by blacksmith

This has been said for 50 years. Rather like the idea that all air to air combat will be with missles it doesn't seem to be happening.

On the other hand, cavalry were used for upwards of 3,000 years and then became basically obsolete within a few decades, so it's not like "X has never happened before" means "X will never happen".

[blacksmith]

Originally Posted by Anthony

On the other hand, cavalry were used for upwards of 3,000 years and then became basically obsolete within a few decades, so it's not like "X has never happened before" means "X will never happen".

So there is nothing filling the role of cavalry now then? Must tell that to the armored cavalry and air cavalry then.

This is not the replacement of an animal with a machine but the removal of a role.

[Panzerfaust]

As far as I am concerned, even in the far off future there will probably be some need for tanks. In a futuristic campaign I am running Tanks, Battle suits, and even mech all have their own special place. But i'll get into that in a moment.

To point this out, by the time battle suits are made cost effective they pretty much have some really nasty tools at their disposal. Most notably hardened armor and Electromagnetic armor for those pesky plasma bolts and shaped charge warheads. Put that on a tank. And make it thicker. Now you not only have something with bigger guns, but it can take a hit from some smart arse in a battle suit and return the favor with something you can bet that battle suit wasn't designed to take a hit from. This is even more apparent if shield technology is around.

Now, in my campaign I have taken that simple fact into account and there is a very distinct use for each of the three heavy armor types. Tanks, the big guys on the field. Don't wanna bump into one of these in urban combat because you can bet that house you're near/using as cover is going to be more shrapnel and exploded death than help.

Battle suits. During an assault on a military building you need intact, or has some sort of tactile importance that it can't be just leveled, would you really want to bump into one in a hallway? I think not. In fact, I am pretty sure that is a sh!t bricks moment when you turn a corner and see a heavy battle suit staring at you with a Gatling laser or a plasma gun.

Now for the whole mech thing. Personally, I hate japans concept of them. I really do. mobile suits of what you might as well consider armor is just... not my thing. But the battle tech universe is where it is at. huge walking tanks with more guns then is feasibly needed. Unless of course you use them for the reasons they are used in my campaign world. Starships with contragrav can get pretty annoying, tanks have issues getting the elevation to hit them and of course terrain kinda mucks up the works there. A mech can get the job done. More guns then a tank, though they are less armored so a bigger reactor can be put in to handle the drive train's power needs as well as all the other weaponry it will have.

[blacksmith]

Originally Posted by Panzerfaust

Now for the whole mech thing. Personally, I hate japans concept of them. I really do. mobile suits of what you might as well consider armor is just... not my thing. But the battle tech universe is where it is at. huge walking tanks with more guns then is feasibly needed. Unless of course you use them for the reasons they are used in my campaign world. Starships with contragrav can get pretty annoying, tanks have issues getting the elevation to hit them and of course terrain kinda mucks up the works there. A mech can get the job done. More guns then a tank, though they are less armored so a bigger reactor can be put in to handle the drive train's power needs as well as all the other weaponry it will have.

This is really funny given how several of the orrigional Mechs where lifted dirrectly from anime sources.

Battletech is very anime inspired.