guidance/en-route error

military technology

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June 29, 2026

Quick Summary

Guidance/en-route error refers to inaccuracies that occur during a missile's flight after launch. These errors can stem from imperfections in the missile's design, particularly its guidance system. Such errors are typically measured by the missile's circular error of probability (CEP) and bias. CEP indicates the radius of a circle containing 50% of impact points, while bias measures the deviation of the average impact point from the intended target. Improving guidance systems is crucial for reducing these en-route errors, which are distinct from launch-point or aim-point errors that can be corrected through more accurate surveying. Tactical weapons systems, which include missiles, are designed for relatively short-range, immediate use and are manufactured by numerous countries.12

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rocket and missile system
Design principles
…generally expressed as launch-point errors, guidance/en-route errors, or aim-point errors. Both launch- and aim-point errors can be corrected by surveying the launch and target areas more accurately. Guidance/en-route errors, on the other hand, must be corrected by improving the missile’s design—particularly its guidance. Guidance/en-route errors are usually measured by a…
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…generally expressed as launch-point errors, guidance/en-route errors, or aim-point errors. Both launch- and aim-point errors can be corrected by surveying the launch and target areas more accurately. Guidance/en-route errors, on the other hand, must be corrected by improving the missile’s design—particularly its guidance. Guidance/en-route errors are usually measured by a…
Read More