From a Google seach on "Red Hat Squadron"...

The Red Hat Squadron is the name given to the fliers of capture/stolen
Soviet aircraft. The Red Hat Squadron operates out of Area 51. It is
speculated they use Hanger 5 at the Area 51, Groom Lake airbase. Resulting
from the foreign material exploitation program named "Red Hat", the Red Hat
Squadron started in the 1960's and has been attributed to the improved
fighter kill ratios in the Viet Nam, the Persian Gulf and Serbia conflicts.
Soviet aircraft in the Red Hat Squadron include the Mig 17, Mig-19, Mig-21,
Mig-23, Mig-27 and Su-27.

"Tarver Engineering" wrote in message
...

"DunxC" wrote in message
...
Hi,

For info, in 1969 the USN flew 'Have Drill' missions with a MiG-19
against
two
loaned ANG F-86Hs. Guess that puts a date for the start of the
programme.

BTW - isn't there an ex-Red Hat MiG-21 in the USAFM?

Red hats are GE, it is an engine thing.