The Bell X-1 Rocket Plane was the first plane to reach supersonic flight in 1947. Captain Chuck Yeagher was the pilot of this plane (also called the "Glamorous Glennis").
Mr. Bob Holder, a former resident of Pequannock, tells us that some of the work done on the X-1 engine was done at Reaction Motors in Pompton Plains (aka: Dunnes Barn). A lot of the people who worked there were from Pequannock Township. The motors made a lot of noise in 1946. The zoning board passed an ordinance against making too much noise. The April 1946 issue of Life Magazine has a picture of the testing of the X-1 Rocket at the Pompton Plains facility. Reaction Motors has the most motors of any manufacturer at the Smithsonian Air and Space Museum.
The plane now hangs at the Smithsonian Institution in Washington D.C. Reaction Motors Historian: Richard Collins Diamond Spring Road Denville, New Jersy