Historical clue formulations

• W.W. I French biplane — 2020-01-19
• Fokker foe — 2011-07-15
• W.W. I fighter plane — 2008-10-28
• W.W. I plane — 2004-10-01
• W.W. I plane — 2002-10-25
• W.W. I Allied plane — 1998-02-22
• Miner's nail — 1994-05-02