UK Commonwealth used In Australia primarily during WW II to train air crews in bombing. When the bomb hit, a small bursting charge would rupture the case and cause the contents to be ignited so the aircrews could observe where the bomb had fallen. Taken from the Defence Unexploded Ordnance Website Ordnance Information Sheet.2 x RAAF 25ib Practice Bombs Inert Models mounted on wooden base without the fuze. The bombs were usually white overall with black, green bands and red band on the noseNonepractice bomb 25 lb raaf smoke flash filling