Lanz-Odermatt Calculator

Simulation Tools · Free

Penetrator & Target

Penetrator Presets ▶

Preset: —

Caliber

Penetrator

ⓘ Data quality indicators:

Complete: all critical specs present

Partial: some estimates

Sparse: missing critical data

Material

Penetrator Geometry

Total Length L

Diameter D

Frustum Length L_f

Frustum Diam. d

Density ρ_p

APFSDS penetrator geometry diagram

APFSDS penetrator geometry diagram

Target

Target Density ρ_t

Hardness BHN_t BHN

Impact Conditions

NATO Obliquity φ °

Impact Angle θ

Impact Velocity V_i

Results

Enter values and click Calculate.

About this tool

This is an implementation of the Lanz-Odermatt model, predicting penetration depth into semi-infinite RHA targets (penetration mode) or the armor thickness a long-rod penetrator can defeat (perforation mode). The underlying math and empirical coefficients are not original work. This tool is based on the calculator by Willi Odermatt. The APFSDS preset data is sourced from a community-maintained APFSDS table.

Working Length L_w

L_w = L − L_f · (1 − (1 + d/D + (d/D)²) / 3)

Main Equation (both modes)

P / L_w = a · (1 / tanh(b₀ + b₁ · L_w/D)) · cos^m(φ) · √(ρ_p/ρ_t) · exp(−s²/V_i²)

In penetration mode the obliquity term cos^m(φ) is omitted (normal impact assumed).

Material Resistance Parameter s²

Tungsten & DU (both modes) / Steel (perforation):

s² = ((c₀ + c₁ · BHN_t) · BHN_t) / ρ_p

Steel penetrator (perforation only):

s² = (c₀ · BHN_t^k · BHN_pⁿ) / ρ_p

Material-Independent Coefficients

b₀ = 0.283 b₁ = 0.0656 m = −0.224

Material-Dependent Coefficients — Penetration

Material	a	c₀	c₁
Tungsten	0.921	138	−0.10
DU	not yet available
Steel	not yet available

Material	Test results	Std. deviation
Tungsten	148	3.9%

Material-Dependent Coefficients — Perforation

Material	a	c₀	c₁	k	n
Tungsten	0.994	134.5	−0.148	—	—
DU	0.825	90.0	−0.0849	—	—
Steel	1.104	9874	—	0.3598	−0.2342

Material	Test results	Std. deviation
Tungsten	99	3.3%
DU	42	3.5%
Steel	40	2.8%