The production of W+W- pairs is analysed in a data sample collected by ALEPH at a mean centre-of-mass energy of 182.7 GeV, corresponding to an integrated luminosity of 57 pb-1. Cross sections are given for different topologies of W decays into leptons or hadrons. Under Standard Model assumptions for the W-pair production and decay, the W-pair cross section is measured to be 15.57+/-0.62 (stat.)+/-0.29 (syst.) pb. Using also the W-pair data samples collected by ALEPH at lower centre-of-mass energies, the decay branching ratio of the W boson into hadrons is measured to be B(W-->hadrons)=68.93+/-1.21 (stat.)+/-0.51 (syst.)%, allowing a determination of the CKM matrix element Vcs=1.043+/-0.058 (stat.)+/-0.026 (syst.). The agreement of the cross sections with the Standard Model prediction allows a limit to be set on the W decay rate to undetectable final states.
