Kartenstapel

1. G – Center of Gravity: Point where the ship’s total weight acts.

2. Vector W – Weight Force: Downward force acting through G.

3. M – Metacenter: Point where the buoyancy force line intersects the centerline when the vessel heels slightly.

4. MG – Metacentric Height: Distance between G and M; key measure of initial stability.

5. K – Keel Point: Lowest point of the vessel.

6. B – Center of Buoyancy (CoB): Center of the displaced water volume; point where buoyancy acts.

7. B′ – Shifted CoB: New position of B when the vessel heels.

8. Vector FB – Buoyancy Force: Upward force acting through B (or B′ when heeled).

9. H – Righting Lever: Horizontal distance between W and FB; creates the righting moment.

10. Δ (Delta) – Heeling Angle: Small angle of heel (typically < 5°)

The ability of a vessel to return to upright position after a small heeling angle.

Archimedes’ Principle.

Heeling moment equals righting moment.

The point where the total weight of the ship acts.

The center of the displaced water volume.

Because the underwater shape and displaced volume change.

Thepoint of intersection of the upward vertical line through the new center Bouyancy Force B’ and the centerline of the ship.

The distance from the Center of Gravity (G) to the Metacenter (M).

The vessel is unstable.

The horizontal distance between weight force and buoyancy force.

Wind, turning, free surfaces, cargo shift, icing, propeller torque.

Stability reduction due to liquid movement in partially filled tanks.

German Naval stability requirements.

Righting levers must exceed heeling levers.

Balance of areas under righting and heeling lever curves.

A₁ > 1.4 · A₂ and static heel < 0.6 · Hmax.

Stability of a ship after flooding due to damage.

Three compartments may be flooded without submerging the bulkhead deck.

Approximately 0.18 × LWL minus 3.6 m.

Frictional resistance, wave resistance, viscous drag.

Appendage and wind resistance.

Full-scale resistance cannot be calculated analytically with high accuracy.

Reynolds and Froude similarity cannot both be satisfied.

Ratio of inertial to viscous forces in the flow.

Ratio of inertial forces to gravity forces (wave effects).

Wave resistance.

Estimating propulsion power from comparable ships.

With PD being the power required at the propeller, Δ the displacement in tonnes, vs ship speed in m/s and Cp being the „Admirality Constant“ obtained from a „comparison ship“. In analog, for the total resistance RT is the relation

Displacement and the cube of ship speed.

It is empirical and based on comparable hull forms only.

Convert rotational power into thrust

Large-diameter, slow-turning propeller.

Local pressure falling below vapor pressure.

Material damage and strong underwater noise.

Fullness of the hull shape.

A slender hull with lower resistance but lower stability

Improved seakeeping and reduced green water on deck.

Cruising speed and maximum speed.

Rolling, pitching, yawing.

Seawater flowing over the deck during heavy seas.

Probabilistic methods in irregular waves.

Speed

Manoeuvervrability

Stopping distance from max. speed

Merchant ships are optimized for transport efficiency, naval ships for combat value.

Combat against enemy surface ships.

Detection and engagement of submarines.

Defense against airborne threats such as aircraft and missiles.

Use and countering of naval mines.

Defense against irregular, unconventional threats (e.g. fast attack boats, terrorism).

Smaller size, coastal focus, limited endurance and armament

Weapons, sensors and mission-related equipment.

Missiles, artillery, torpedoes and mines.

Heavy torpedoes target ships; light torpedoes target submarines.

Detection, tracking and situational awareness.

Simultaneous detection and tracking of multiple targets.

They provide passive detection and high-resolution targeting.

They act as mobile sensor and weapon platforms.

Stand-off sensing and weapon deployment, extending operational range.

Fast Patrol Boats, Corvettes, Frigates, Cruisers, Aircraft Carriers, MCM vessels.

Use of the electromagnetic spectrum to sense, attack or protect.

Electronic Support Measures (detection) and Electronic Countermeasures (jamming/deception)

A system integrating sensors and weapons to support decision-making.

The tactical situation picture.

It connects operators with complex combat systems.

Detectable characteristics such as noise, radar, IR and magnetic fields.

A measure of how detectable a ship is by radar.

Defensive systems like CIWS and decoys.

Structural protection, compartmentation and damage control.

To maintain survivability after hits or flooding.

Archimedes’ principle.

Weapons, sensors and operations require stable platforms.

To survive explosions and weapon impacts.

They define safety and design standards.

Frictional resistance, wave resistance and viscous drag.

They characterize flow similarity and scaling effects.

Full-scale resistance cannot be predicted accurately otherwise.

Numerical simulation of flow, resistance and propulsion.

Diesel engines, gas turbines and electric propulsion.

To optimize efficiency at different speeds.

Rolling, pitching and yawing.

Seawater flooding the deck in heavy seas.

Mission, weapons, sensors, endurance and survivability.

It allows flexible upgrades and role adaptation.

Diving, trim, stability and low signatures.

Sensors, weapons and CMS adapted for underwater warfare.

Reduced crewing needs and increased operational flexibility.

Decision support, automation and data fusion.

Energy efficiency and sustainability.

Naval ships require high acceleration, redundancy, low signatures, and flexible speed profiles.

At cruising and medium speeds.

High fuel efficiency, reliability, and long endurance.

Higher vibration, noise, and limited power-to-weight ratio.

Ship behavior in waves and sea states.