Rocket-assisted projectile

A rocket-assisted projectile (RAP) is a cannon, howitzer, mortar, or recoilless rifle round incorporating a rocket motor for independent propulsion.

This gives the projectile greater speed and range than a non-assisted ballistic shell, which is propelled only by the gun's exploding charge.

These rounds were high explosive shells or shaped charges with a maximum range of 6 kilometres (3.7 mi).

The North Korean M-1978 / M-1989 Koksan 170 mm (6.7-inch) self-propelled gun can use rocket-assisted projectiles to achieve a range of around 60 kilometres (37 mi); at one time this was the world's longest-range tube field artillery piece.

[1] When NATO standards required member armies to have corps-level artillery that could fire to a minimum range of 30 kilometres (19 mi), nearly all member nations solved the problem with RAP rounds in their 155 mm (6.1-inch) artillery.