Ketch ketch and the yawl have two masts, with the main mast foremost; the distinction usually being that a ketch has the mizzen mast forward of the rudder post, whereas on a yawl, it is aft of the rudder post. But the balance of sail area can be an overriding characteristic. If 20% or more of the sail area is in the mizzen sail the rig would be termed a ketch. This is particularly true on center cockpit yachts. Compared to a ketch, a similar size yawl's mizzen sail is much smaller than the main, because of the limitations of the
Radio masts and towers In Germany the Bielstein transmitter collapsed in 1985. Tubular masts were not built in all countries. In Germany, France, UK, Czech, Slovakia, Japan and the former Soviet Union, many tubular guyed masts were built, while there are nearly none in Poland or North America. In several cities in Russia and Ukraine several tubular guyed masts with crossbars running from the mast structure to the guys were built in the 1960s. All these masts, which are designed as 30107 KM, are exclusively used for FM and TV transmission and, except for the mast in Vinnytsia, are between 150 and 200 metres