A Military Operations Area (MOA) depicted on a sectional chart indicates:
Why →
MOAs separate certain military training from IFR traffic and advise VFR pilots of potential hazards. Unlike Restricted Areas, no clearance is required to enter a MOA. However, pilots should exercise extreme caution when the MOA is active. ATC can advise on current activity level.The trap →
MOAs don't prohibit entry for non-military aircraft. That's the difference from Restricted and Prohibited Areas. "Can enter without clearance" doesn't mean safe when active. High-speed military aircraft at low altitude in an active MOA present a genuine collision risk.SOURCE → FAA AIM Chapter 3CHECKED APR 21ACS II.A.K3EASY