Complex sentence: Until this time the British, at RAF insistence, continued their World War I use of machine guns, and introduced twin MG mountings for AAAD, the army was forbidden from considering anything larger than.50-inch.
Split into simpler sentences: Until this time the British, at RAF insistence, continued their World War I use of machine guns, and introduced twin MG mountings for AAAD. The army was forbidden from considering anything larger than.50-inch.