How to Make Mecha Work in a realish setting

[Moik]

Or trucks.
Optimus Prime was a truck.

[bunnyboy]

I can't think of any terrain a Tank can traverse that a mech couldn't while thats not true in reverse.

Stairs. If the foot does not fit into step or it get misplaced, the mecha falls down like Asimo. A tank doesnt care if it stairs or side of hill. Also, more steep hills favor lov profile vehicles and tank might even climb slope where mecha could get stuck if the high slope prevents it of lifting its knee.

[MBehave]

Did you bother reading anything before posting?
Did you miss my post on how based on current synthetic muscles etc Mechs would actually be cheaper then Tanks?
The reference of a combustion engine?
Actual energy/fuel required?
Lower wear due to reduced friction of bipedal movement over tracked?

10 ton mech doesn't need much fuel to be active longer then a tank on the battlefield, It could likely be stored internally in its own armoured section and then something like an extended external fuel tank it drops in combat if extended operating times are wanted.

Combustion engines are not finicky at all if they are using injectors and vacuum bladders.
Basicly what most planes were using by the end of WW2.

Tanks are not cheap, they are expensive ~10 million a pop and service costs are horrible, the actual outright cost of a Tank is not the main problem its the upkeep costs.

WW2 Sherman would cost around ~$600k USD today to make.
4 tracks for a M1A2C costs about the same.

Artillery round that deploys 2 antitank payloads costs $57k USD
APFSDS round for a 120mm smoothbore cannon costs around $10k USD
Hellfire anti tank missile costs around $75k USD

Tanks are not cheap.
Maybe they are even outdated on the battlefield today in equal technology combatants.
Much like the Battleship failed in WW2.

Reading about M1A1 tanks that were destroyed, if they suffer ammo cook off or duration fuel fire, the heat destroys the armours effectiveness elsewhere.
You can't just take the hull and slap another turret on it like ww2.


Also why if a mech loses an arm or leg other parts be used on another mech?
If you can make 3 mechs for 1 tank you now have 3 targets those smart rounds need to target and destroy.
Sending 100 men in 100 mechs worth 100 million dollars seems better then sending 133 men in 33 tanks worth 100 million.

I will admit Mechs being effective requires them to be cheaper then tanks.
As I said before, its not Tank vs Mech its Tank cost vs mech cost.

Instantly detected and destroyed?
How is that different to tanks?
Tanks are already detected through ground and air vibrations including type, as is artillery fire, infantry, aircraft.

Smart artillery rounds carry 2 anti tank warheads and have a range of around 28km.

Funny enough the radar systems of those artillery shells would have more trouble trying to pick out a mech on the terrain then a tank when dealing with 3m high mechs.

Ignoring active defenses for both tanks and mechs, why would mechs be instantly destroyed but the tanks survive?

Tanks are designed for two things in mind: survivability and recyclability.

Survivability is simple, strap armor that is sturdy enough to keep the machine intact against most weapons.
Recyclability is also simple: in case of a mission kill make the tank easy to be recovered and brought back into action. Despite their complexity most tanks are designed to be able to return into action in a matter of hours provided the mission kill was merely a catastrophic engine/track damage. Same with gun damage, even armor damage. Provided that the main chassis and the turret ring is intact a field maintenance depot is able to return most of the ordinary mission kills back into the fray in less than a day provided a proper logistics chain is available. Recycling is the reason as to why many armies suffered larger total tank loses in battles than the total number of tanks fielded, this is particularly noticeable in the desert war of north Africa in WW2.
I wouldn't want to be a tanker in a war; it is far more probable that I would be killed and the tank would end up recycled than unscathed survival.

By their nature mechs would be impossible to recycle in mission kill situations. Not only is the machinery highly complex and expensive making field maintenance a night mare but just the fall damage would severely damage other otherwise unharmed components.
The expected nature of their engines is also dubious, in case of fisson or fusion based powerplants then a powerplant failure/mission kill (the most frequent reason for mission kills for tanks) makes recycling impossible due to radiation leakage alone. This is the reason as to why the early cold war concepts of 'nuclear engines' for ships, airplanes and tanks was shafted; it's simply impossible to salvage any equipment that has been bathed in radiation. Anti-matter and other similar high tech generators? Same deal but even worse because of the booms they make.

Scrapping the whole power plant angle and going for good old internal combustion engines?
Those are really finicky when they are violently shaken (see mech running) and dropped (see mech falling). The large amounts of fuel would also pose extreme problems in terms of stability since the fuel consumption would alter the moving characteristics of the mech (much in the same way of airplanes) with the added problem of balance on top. You think that standing tall under fire is hard? Try to stand up while taking hits after one of the fuel tanks is catastrophically ruptured while the other one is intact. To see the difficulty on balancing while carrying uneven weights try to run in a field while strapping a few dozen kilograms of extra weight on the arm and leg of one side of your body.

In short, tanks are relatively cheap weapon platforms that are designed to come back from the dead because they will be a priority target by the enemy. Mechs? By their nature far harder to do so in a realistic setting.

Certain things in realistic settings cannot be hand waved away. For Mecha you either provide magic tech or a plausible niche to make them viable.

[bunnyboy]

So lets then make whole tank move like snail by using synthetic muscle at bottom. It can go every where, grab on every surface and travel even upside down by hanging. The speed will not be impressive, but it can lift enough armanent and armor to whole army of mechas with only fractions of cost.

[Arioch]

The argument is going in circles, and people are starting to get nasty. Everyone has had their say; I don't think this thread can serve any further constructive purpose.