  The work analyzes existing methods for increasing the accuracy of determining
weekend navigation parameters of unmanned underwater vehicles. It is proposed
to retrofit the navigation system with an additional hydrodynamic tilt unit,
which will increase accuracy of coordinate determination. A prototype of the
proposed system was made, and algorithmic software for it. Analysis of typical
MEMS errors has been completed accelerometers and gyroscopes. To estimate
stochastic errors, the Allan variation method was tested using a set of real
data obtained on a prototype as input parameters. A model of stochastic errors
of all measuring channels has been constructed
