1942-1948
Consolidated Vultee Aircraft Corporation (Convair) brought together Consolidated Aircraft of San Diego and Vultee of Downey.  Practically every type of military aircraft from small, single engine, civilian defense trainers to huge, multiple engine land and sea bombers were produced in the diversified plants of the companies. 11,537 trainer aircraft (Valiants) had been produced at the Vultee field. Also, in the first 6 months of 1944, Convair at Vultee field helped turn out the largest delivery of heavy bombers (B-24 Liberators) produced in the country. At the end of World War II production of military aircraft at the Downey plant was nearing an end. The Vultee Field division of Convair remained open to support a contract with the Navy for a short-range missile called the Lark.
The Lark was a surface -to-air missile with a range of 35 miles and a speed of 300 knots per hour.

Quotes and reference from "Final Historic Buildings and Structures Inventory and Evaluation- NASA industrial Plant Parcels 1 and 2)

1942-1948 With a foot in the door of the newly emerging missile industry, the Vultee Field division of Convair was awarded a $1,2 million contract by the government to study long-range missile weapons systems. The study was called project MX-774 and was designed to study two types of missiles: a subsonic, jet engine cruise missile and a rocket-powered supersonic ballistic missile. Downey's engineers focused on the ballistic missile concept and used information about the German V-2 rocket as a starting point. Although the MX-774 program was eventually canceled by the Defense department, the Downey Division was developing numerous other projects including the Y-P1 fighter plane and components for the huge XP-38 bombers.
The Vultee plant was also engaged in the engineering and manufacture of a "guided missile which carries power equipment providing for travel outside the atmosphere of the earth. 

"Indeed, the MX-774 was described as a "streamlined" version of the German V-2. The missile was 31 feet, 7 inches long by 2 feet, 6 inches wide and had a finspan of about 6 feet. It weighed 1,200 pounds empty". Convair continued ballistic missile research and design work following the expiration of the MX-774 project. At the time, U.S. Air Force funding centered around more conventional winged cruise missile applications, most notably the Navajo, built by North American".

By early January 1946, the Downey engineers had roughed out their ideas on two types of 5,000-mile missiles: one subsonic, winged, and jet powered; the other supersonic, ballistic, and rocket powered. A study program was proposed to the Air Force to determine which type would best serve the ultimate purpose. In April, Convair received a contract for $1,400,000 for a year's study of under Project MX-774. Captive testing of the MX-774 research rockets began in San Diego in 1947. A year later, three MX-774's were test-launched at White Sands Proving Ground, New Mexico. The flights proved the value of three important innovations: gimbaled engines for directional control, lightweight, pressurized airframe structure, and separable nose cones. But defense cutbacks in 1947 forced the Air Force to shelve the ballistic missile in favor of other weapon programs.Continued