The model is developed for forecasting of changes of size physical in the real time, based on use of the linear adaptive filter. At the heart of the filter the autoregress model lies. The scheme of performance of forecasting which consists in realisation of the procedure consisting of three stages is offered. At the first stage the index point choice on a surface for minimisation of a square of an error of the forecast is carried out. The second stage is devoted definition of a direction of movement on a surface for the purpose of an error minimum. At the final stage definition on each step of movement of the new modified scales of a vector which minimises a forecast error is carried out. Researches of possibility of use of an adaptive time number for forecasting of change of physical size on the basis of the data about change of the acceleration, removed with 3 axial акселерометра, established on the car are conducted. The developed model and a forecasting technique can be used at realisation of the tentative estimation defining a condition of parametre of technical object.