Steve76,
The fantail that we flew in the early 1990's (first flew in June of 1990) was an experimental S-76B with a fan grafted on as a test bed for the fan that was finally flown on the Comanche. The 76 was a convenient platform for the test flights, and production of a 76 fan was never considered.
That was the aircraft where we invented the "snap turn" where we can pivot at speeds up to 120 knots and point independent of the direction of flight.
Here is a picture of it taken at Paris the next year:
http://www.zap16.com/images/N3124G.jpg