The 155 mm M549/M549A1 HERA is a separate-loading munition with a two-part forged shell body. The forward HE-filled shell body is constructed from high-fragmentation steel (HF1) and is of a low-drag aerodynamic profile.

The M549A1 is an extended range, rocket assisted high-explosive projectile for use in long range harassment and interdiction (H&I) fire missions. The rocket motor is located in the aft end of the two-piece forged alloy projectile body. The rocket is initiated by a pyrotechnic delay which ignites upon a gun launch and provides a 7-second delay. This

2017年10月16日 · With lethality equal to the legacy M549A1 but exceeding its range by at least six miles, this projectile is under consideration as part of the C-DAEM suite of munitions.

The 155 mm M549/M549A1 HERA is a separate-loading munition with a two-part forged shell body. The forward HE-filled shell body is constructed from high-fragmentation steel (HF1) and is of a low-drag aerodynamic profile.

These projectiles consist of two major components, a warhead filled with 16 pounds of Composition B high explosive (M549) or 15 pounds of TNT high explosive (M549A1), and a solid propellant rocket motor. These components are threaded together so that the outer steel shells of both form a streamlined ogive.

Delay assemblies required very high temperatures 375 degrees F and 475 degrees F to cause failure due to temperature alone. When humidity was introduced into the test matrix, the delays failed at much lower temperatures 1 55 degrees F to 230 degrees F.

These projectiles consist of two major components, a warhead filled with 16 pounds of Composition B high explosive (M549) or 15 pounds of TNT high explosive (M549A1), and a solid propellant rocket motor.