C-3
C-3 stands for Collagen Type 3
C-2X
C-2X stands for Coalition Intelligence Directorate Counterintelligence and Human Intelligence Staff Element (US DoD)
C-21
C-21 stands for Gates Learjet
C-141
C-141 stands for Starlifter
C-123
C-123 stands for Provider (cargo aircraft)
C-100
C-100 stands for Environmental Control Unit for DEPMEDS
C-12
C-12 stands for Huron (cargo aircraft)
C-1 ARMY
C-1 ARMY stands for Introduction to Federal Supply Catalogs & Related Publications (Army)
C-130
C-130 stands for Hercules
C-140
C-140 stands for Jetstar