Geometric properties of reliability polynomials

Geometric modeling of multivariate reliability polynomials is based on algebraic hypersurfaces, constant level sets, rulings etc. The solved basic problems are: (i) find the reliability polynomial using the Maple and Matlab software environment; (ii) find restrictions of reliability polynomial via equi-reliable components; (iii) how should the reliability components linearly depend on time, so that the reliability of the system be linear in time? The main goal of the paper is to find geometric methods for analysing the reliability of electric systems used inside aircrafts.