Well my Brison 3.2 with Bisson pitts muffer and ignition is 4.3lb and radio prop spinner and hardware is 3.1lb, 5 hitec 5945 1futaba 3001 and 2 1100ma at 6v 1 1100ma 4.8v 2 mpi switch LED type 1 super rocker switch on ignition carbon push rods and rocket city control horns dave brown spinner 22x8 Biela carbon prop all stock hardware except tail wheel witch i made a lighter one. I m not camplaining about the weight as the plane flys great, still hovers at little over half throtle with power to pull out. I,m just saying it won't be 15.5lb with the stock hardware that came with the plane unless the BME 50cc is 2lb lighter than the Brison3.2.