What is STANAG 4569? What do the protection levels mean?

STANAG 4569 is the NATO standardization agreement that defines, on a common scale, the protection provided to the crews of logistic and light armoured land vehicles (details are in the AEP-55 document). It turns the question “how well does this vehicle protect against which threat?” into measurable levels that everyone reads the same way.

Three threat groups

• Ballistic threat: Kinetic-energy threats that start with small-arms rounds and extend at higher levels to automatic cannon rounds, up to 30 mm calibre.
• Artillery fragments: Protection against fragments produced by the burst of artillery ammunition. As the level rises, the required proximity of the burst to the vehicle also becomes more demanding.
• Mines and improvised explosive devices: Protection against a charge detonating under the vehicle, under a wheel or track, or under the hull.

What do the six levels mean?

Level 1 is the lowest and Level 6 the highest protection. Level 1 protects against small-arms rounds and artillery fragments from a distance. As the levels rise, more powerful rounds, closer burst distances and heavier mine charges are targeted. Level 6 extends to automatic cannon rounds.

Note: The exact test parameters of the levels (projectile type, distance, explosive mass) are given in the current edition of the document. The official AEP-55 text should be consulted for precise values.

How do you choose the right level?

The highest level is not always the right choice. As protection increases, so does weight, which affects mobility, fuel consumption, transportability and cost. The level is chosen by answering the following questions together:

• In what mission and in which region will the vehicle be used?
• What is the highest expected threat?
• What are the accepted limits for weight, speed and range?
• Will an upgrade with add-on armour be needed later?

In many projects the hull and subsystems are designed for a lower base level, and a higher level can be reached with add-on armour packages. For this, the load-bearing structure, suspension and power pack are sized from the start for the additional load.

“Designed to the standard” and “certified” are not the same thing

Designing a vehicle to STANAG 4569 means building the target level into the engineering calculations and design rules. Being certified means passing the ballistic and mine tests carried out at an independent test body. They are separate stages and must not be used interchangeably in a project.

What does YDD Technology do in this process?

We define the target protection level together with the customer, design the hull and subsystems for that level, and verify the balance between weight and mobility with analyses. In the testing and certification phase we provide a test plan and design data support suited to the project requirements. You can contact us to describe your project.

Published: 2026-10-26