Aircraft components in real combat environments are frequently exposed to threats from high-speed penetrating projectiles such as explosive fragments and bullets. Enhancing their anti-penetration capability is critical to ensuring the safe operation of aircraft. Ultra-High Molecular Weight Polyethylene （UHMWPE） fabric， renowned for its lightweight nature and exceptional strength， has been widely adopted in ballistic protection applications. This study focuses on UHMWPE plain weave fabrics， employing ballistic impact experiments and meso-scale numerical simulations to systematically investigate the effects of projectile geometry， impact velocity， and penetration angle on its ballistic resistance and damage mechanisms. The results reveal that UHMWPE plain weave fabrics subjected to ballistic impact primarily exhibit a cross-shaped deformation zone accompanied by a distinct pyramidal back protrusion. Compared to spherical projectiles， flat-nosed projectiles demonstrate lower penetration capability and a higher ballistic limit velocity. This is attributed to the larger contact area between flat-nosed projectiles and the fabric， which induces broader deformation zones and shear plugging-dominated failure. In contrast， spherical projectiles tend to cause yarn slippage and pull-out within the fabric. Additionally， the penetration angle of flat-nosed projectiles significantly influences the fabric’s energy absorption capacity. As the impact angle increases， the fabric’s anti-penetration performance deteriorates. This research provides critical insights into the ballistic failure mechanisms of UHMWPE plain weave fabric and offers a foundation for optimizing the design of high-performance fiber-based protective materials.