The Lockheed J37 (company designation L-1000) was one of the first turbojet engines designed in the United States. It was not considered very important when its development was first begun in the 1930s, and it was allowed to languish. By the time it was developed enough for production use, other engines, some British-derived, had surpassed it in performance. The design was later converted to a turboprop, the T35 and still later sold to Wright Aeronautical, where it saw some interest for use on what would become the B-52 Stratofortress, before that design moved to jet power. The J37 and T35 were built to the extent of a number of testbed examples but never entered production.