Glenbrook Tunnel War One. The first was Chlorine gas which was introduced by the Germans at the Second battle of Ypres in April 1915. This was followed by the use of Phosphene Gas, also introduced by the Germans. These attacked victims' respiratory organs causing coughing and choking. The Germans used Mustard Gas, a more advanced gas, for the first time at Riga (or Yperite) in September 1917. It caused both internal and external blistering in its victims. The blistering was often delayed and remained in the ground for weeks afterwards making capture of infected trenches dangerous. Protection against mustard gas was far
Nielsen & Winther Type AA Nielsen & Winther Type AA The Nielsen & Winther Type AA, also known as the Type AA, was a Danish fighter aircraft of the 1910s. The first Danish fighter aircraft to be conceived and built, the single seat Type AA was of wooden construction and powered by a 90 hp Thulin rotary engine. It was armed with two guns. The first flight took place on 21 January 1917. The plane was tested again in 1918, this time with synchronising gear for its single Madsen machine gun. During 1917 six Type AA aircraft were delivered to the Danish Army, though they