The article proposes an approach to the quantitative assessment of the effect of metrological reliability of measuring equipment on the time of the verification of the parameters of military communications means during its maintenance and current repairs. In known works, approximate values of the probability of failure-free operation of measuring instruments are used for this, which reduces the accuracy of the results obtained. In the field conditions, it is necessary to take into account the metrological reliability of measuring instrument, which depends on temperature, humidity, vibration loads and other factors. The time for determination of the technical state of military communications means is regulated by guidance documents, therefore it is necessary to take into account all factors influencing the values of maintainability indicators in order to plan efficient work of specialists during its technical maintenance and routine maintenance in the process of developing metrological and diagnostic support. It is suggested to use the functional dependencies of the average recovery time of military communications equipment on the quality indicators of metrological and diagnostic support. Examples are given of using the results of the study to quantify the maintainability of real samples of military communications means and show the gain in the accuracy of calculating the average recovery time. The received results allow to estimate more objectively time of performance of works and reasonably to choose measuring instruments more objectively.