Project SQUID was a United States defense effort post-World War II effort to develop and improve pulsejet and rocket engines, run by the Office of Naval Research.https://books.google.com/books?id=gz8hwSolMaAC&dq=project+squid+pulse+jet&pg=PA422
It was started by discovery of the German Argus As 014 pulsejet used on the V1 buzzbomb, which was reverse-engineered as the Republic Ford JB-2, the first American cruise missile. It produced extensive research in the areas of computational flow dynamics https://web.archive.org/web/20120227061519/http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA953001, and was used to improve the design of the experimental Fairchild XH-26 Jeep Jet, which used pulsejets on the rotor tips instead of a central engine. The research led to development of pulse detonation engines, which have been suggested as the engines powering the postulated Aurora spyplane.