Bipropellant

Northrop Grumman has a proud heritage of providing bipropellant rocket engine technology to meet the most demanding applications.

We are the only rocket manufacturer that uses pintle injector technology in liquid and gel bipropellant rocket engines. This unique configuration for injecting propellants into combustion chambers provides deep throttle capability(>20:1) with high combustion efficiency and inherent combustion stability. The pintle injector also allows us to build rockets that pulse extremely fast (e.g., 2 millisecond pulse at 100 Hz rate) and that can also lock-up the liquid or gel propellants at the injection point so that none dribble out into the chamber during off times. Northrop Grumman offers several pintle engine designs for space and tactical applications.
 
Northrop Grumman's bipropellant engine experience includes scaling over 130,000:1 in thrust and 250:1 in chamber pressure, and operations with 25 different propellant combinations. To date, the smallest bipropellant pintle engine has provided 5 lbf and the largest has produced 650,000 lbf.

More than 130 Northrop Grumman bipropellant engines have used a pintle injector to fly successfully without one instance of combustion instability. Flight programs that have relied on this technology include Apollo LMDE, Delta launch vehicle 2nd stage, MMBPS, ISPS, ANIK E-1/E-2, Intelsat K, ERIS KKV stage, FMTI, and the Chandra X-ray Observatory.