Indeed. If there is no need for them to show you, they won't, ever. Tacit blue stealth airframe was built in 1982, flown, 'possibly' flown in testing over soviet russia and Iran (ufo sightings of airframes very similar), and retired and NEVER declassified until an accidental reference to it in 1995.
It made 135 flights, flew 4 times a week and logged an amazing amount of testing air time.
It is the 'mother' of all Northrop stealth aircraft, and is considered to be the most successful stealth airframe ever built in a development stage. Had it been rolled out into general service and made frontline, no doubt it would of been a formidable weapon system.
http://uk.youtube.com/watch?v=r4uTZn0TD-o
brilliant video all about it and rare video footage of it in flight.