Originally posted by DarkStar86
For one. Although its finally admitted by the government and is studied by hundreds of thousands of people there are still no substancial evidence on
what exactly goes on there from the late 70's to present day.
As the base was being studied more and more the government was getting nervous and snagged more land so we couldn't see it as well.
Since then to my knowledge their external aircraft test have either stopped or have been decreased severly. But, everything else seems to be operating
as normal.

We do actually know some information after 1980 which indicates that the base is still used for aircraft testing.
In 1981, Senior Trend (YF-117a) was delivered to Groom Lake and made its first flight. In 1982 the first F-117a arrives at Groom Lake, Tacit Blue made
its first flight and project Have Glass was initiated to reduce the RCS of the F-16.
Between '83 and '85, the HALSOL UAV flew at Groom Lake and Tacit Blue made its final flight. Evaluative test flights of the Russian MiG-23 took
place. The F-117a flew out of Groom Lake until 1992. Around '95 the still classified YF-113G flew at Area 51 and in 1996 the Boeing tech demonstrator
Bird of Prey also flew there.
In 1999 a fire broke out on Groom Mountains and is widely believed to have been caused by a crashed test plane. In 2001 the F-22s was flown at Groom
Lake for airborne RCS evaluation and in 1993 additional fuel tanks were contructed.
All this points towards active flight testing at Groom Lake and the lack of recent information can be attributed to the obvious reason that more old
information is declassified on unclassified than recent info.