Historical clue formulations

• ___ plane — 2018-06-09
• High-tech surveillance acronym — 2015-03-29
• ___ plane — 2011-06-24
• Military plane acronym — 2011-05-09
• High-tech surveillance acronym — 2011-01-05
• High-tech surveillance acronym — 2007-08-18
• Military plane acronym — 2006-06-30
• ___ plane (military craft) — 2005-01-03
• Eyes-in-the-skies acronym — 2002-07-05
• Radar-equipped plane — 2002-03-13
• Gulf war planes — 2000-11-26
• Sophisticated military plane — 1999-09-21
• Modern surveillance tool — 1998-06-30
• Military plane acronym — 1997-05-20
• Radar system acronym — 1995-08-04