New improved bounds for reliability of consecutive-k-out-of-n : F systems

New bounds are found for the reliability of consecutive-k-out-of-n:F system s with equal component failure probabilities. The expressions involved are simple, thus allowing a direct use in the derivation of theoretical propert ies. These bounds can also be employed in numerical computations when the value of n or k is so large that the exact calculation of the reliability is not achievable. Comparisons show that the approximation errors exhibited by the se new formulas are lower than those of other widely used bounds.