This video discusses experimental naval railguns and the enormous power systems needed to operate them.

What a Railgun Is

A railgun is an electromagnetic launcher that accelerates a metal projectile using electricity instead of gunpowder.

Basic concept:
1. Two parallel metal rails
2. A conductive projectile (armature) bridges them
3. A massive electric current flows through the rails
4. Magnetic force accelerates the projectile down the rails

Because of the extremely high current, railguns can launch projectiles at over 3 km/s, much faster than conventional artillery.

Instead of explosives, damage comes from pure kinetic energy.

Where Railguns Are Currently Used

Railguns are not widely deployed yet. They exist mainly as experimental military systems.

Current Research / Testing

Countries experimenting with them include:
• United States
• Japan
• China
• European research labs

Example:
• Japan tested a 20-foot, ~8-ton naval railgun capable of hypersonic projectiles around Mach 6+.

Primary research uses:
• Naval artillery replacement
• Hypersonic projectile launch
• Missile interception experiments
• Experimental electromagnetic propulsion

Most programs remain prototype or experimental or off world

Sizes of Railguns

Railguns vary dramatically in scale depending on purpose.

Small Laboratory Railguns

Typical size:
• 1–3 meters long
• used for physics experiments
• powered by large capacitor banks

Example research devices can accelerate small projectiles to ~2-2500 m/s.

Medium Research Railguns

Examples:
• University or military lab systems
• 3–6 meters long
• multi-megajoule energy systems
• projectile mass ~100–300 g

Large Naval Railguns

Prototype naval systems:
• 6–20+ meter barrels
• projectile speeds Mach 6–7
• energy per shot ~20–30 megajoules

They require ship-scale electrical power systems.

A standard Railgun uses two conductive rails with a projectile bridging them. When a massive electrical current flows through the rails and the projectile, a magnetic field forms. The interaction of current and magnetic field creates Lorentz force, accelerating the projectile forward.

Basic system parts:
• two conductive rails
• power supply (capacitor bank / generator)
• conductive projectile or armature
• insulating barrel structure

Current path:

Power → rail → projectile → second rail → back to power supply.

Because the current in each rail flows in opposite directions, a strong magnetic field forms between them, pushing the projectile down the barrel.

⸻

Typical Sizes

Laboratory systems
• 1–3 m long
• small projectiles
• used for physics experiments

Military prototypes
• 6–10+ m barrels
• multi-ton installations
• megajoule energy pulses

⸻

Advantages
• extremely high projectile speed
• long range
• projectiles don’t require explosives

Disadvantages
• rails wear out quickly
• enormous power requirements
• heavy infrastructure needed

Example concept:

Instead of a solid projectile, the launcher accelerates plasma.

How It Works

A Plasma Railgun still uses two electrodes like a normal railgun, but the armature is replaced with ionized gas (plasma).

Steps:
1. gas becomes ionized into plasma
2. current flows through plasma between rails
3. electromagnetic forces accelerate the plasma forward

This produces a jet of extremely fast plasma.

⸻

Uses

These devices are usually not weapons.

They are used in:
• plasma physics research
• fusion experiments
• high-energy density physics
• spacecraft propulsion studies

Some plasma railguns can accelerate plasma to tens or hundreds of km/s in laboratory experiments.

⸻

Typical Sizes

Research devices:
• 0.5–2 meters long
• vacuum chamber setups
• powered by pulsed electrical systems

A Helical Railgun is essentially a hybrid between a railgun and a coilgun.

How It Works

Instead of straight rails alone, the system includes a helical electromagnetic winding around the rails.

Current path:
1. current flows through rails
2. sliding electrical contacts on the projectile activate the helical winding
3. the winding creates additional magnetic acceleration

This means the projectile interacts with both:
• rail current
• magnetic coils

This can reduce the extreme current required by normal railguns.
Historical Prototype

One early experimental system at MIT:
• about 3 meters long
• powered by large capacitor banks
• launched small gliders in experiments.

⸻

Advantages
• lower current requirement
• potentially more efficient

Disadvantages
• complex electrical contacts
• still experimental

Coilgun (Gauss Gun)

A Coilgun is the most well-known electromagnetic launcher alternative.

How It Works

Instead of rails, a coilgun uses a sequence of electromagnets (coils).

When powered sequentially:
1. first coil pulls projectile forward
2. next coil activates as projectile passes
3. magnetic field continues pulling it down the barrel

The projectile never touches the barrel, which reduces wear.

⸻

System Components
• magnetic coils along barrel
• timed switching electronics
• ferromagnetic projectile
• energy storage (capacitors or batteries)

Each coil turns on briefly to pull the projectile forward.

⸻

Typical Sizes

Hobby / experimental
• 20–60 cm long

Laboratory
• 1–3 meters long

Research launchers
• multi-stage accelerators several meters long

⸻

Advantages
• less mechanical wear
• easier to miniaturize
• quieter operation

Disadvantages
• lower efficiency than railguns
• complex timing electronics required