Editing Solid-propellant rocket (section)

===Composite modified double base propellants===
Composite modified double base propellants start with a nitrocellulose/nitroglycerin double base propellant as a binder and add solids (typically [[ammonium perchlorate]] (AP) and powdered [[aluminium]]) normally used in composite propellants. The ammonium perchlorate makes up the oxygen deficit introduced by using [[nitrocellulose]], improving the overall specific impulse. The aluminium improves specific impulse as well as combustion stability. High performing propellants such as [[NEPE-75]] used to fuel the [[UGM-133 Trident II#Design|Trident II]] D-5 [[SLBM]] replace most of the AP with [[polyethylene glycol]]-bound [[HMX]], further increasing specific impulse. The mixing of composite and double base propellant ingredients has become so common as to blur the functional definition of double base propellants.