Krupp's Formula Calculator
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Historical Background
Krupp's formula, developed by German steel manufacturer Krupp in the early 20th century, was used to calculate the required thickness of armor to resist naval shell impacts. This formula was especially important during the era of dreadnought battleships, where naval armor design had to balance protection with weight limitations. It became a cornerstone of military engineering, guiding shipbuilders in creating more resilient battleships and armored vehicles.
Calculation Formula
Krupp's formula estimates the required armor thickness (in centimeters) to resist penetration by a naval shell:
\[ \text{Armor Thickness (cm)} = \text{Caliber (mm)} \times \left( \frac{\text{Impact Velocity (m/s)}}{2400} \right)^{1.5} \]
Where:
 Caliber is the diameter of the shell in millimeters.
 Impact Velocity is the velocity of the shell when it strikes the target in meters per second (m/s).
Example Calculation
If a shell has a caliber of 300 mm and strikes a target at 800 m/s, the required armor thickness would be calculated as:
\[ \text{Thickness} = 300 \times \left( \frac{800}{2400} \right)^{1.5} = 300 \times 0.2963 = 88.89 \text{ cm} \]
So, approximately 88.89 cm of armor would be required to stop the shell.
Importance and Usage Scenarios
Krupp’s formula is significant for historical studies in naval architecture and military engineering. It helped in designing battleships during the early 20th century and is still relevant in understanding the principles of armor and ballistics in military technology. Today, it is mostly used for academic purposes and by enthusiasts of naval history and historical warship design.
Common FAQs

What is the purpose of Krupp’s formula?
 Krupp’s formula helps in determining the required armor thickness to prevent the penetration of naval shells based on their caliber and velocity.

Why is the factor 2400 used?
 The factor 2400 in the formula is derived empirically and relates to the velocity and penetration characteristics of shells used during the time the formula was developed.

Is Krupp’s formula still used today?
 While no longer used in modern military applications, Krupp’s formula is of historical importance and is still studied in the context of early 20thcentury naval warfare.
Krupp’s formula calculator is a helpful tool for those studying naval history and military engineering, giving insights into the design considerations of historical warships and armored vehicles.