Northrop Grumman [NOC] said on Monday that it has delivered 21 satellites to Vandenberg Space Force Base, Calif., for Tranche 1 of the U.S. Space Force Space Development Agency's Transport Layer (T1TL). That layer is to have hundreds of low-Earth orbit satellites to speed secure, military communications. The Transport Layer and the Tracking Layer for missile deterrence are the major components of SDA's future Proliferated Warfighter Space Architecture (PWSA). T1TL is to have 126 satellites--42 by Northrop Grumman, 42 by…