MAHENDRAGIRI, India (ISRO PR) — Today, VSSC/ISRO successfully tested a hybrid motor at ISRO Propulsion Complex (IPRC), Mahendragiri, supported by Liquid Propulsion Systems Centre (LPSC/ISRO). The motor used Hydroxyl-terminated polybutadiene (HTPB) as fuel and liquid oxygen (LOX) as the oxidizer. Unlike solid-solid or liquid-liquid combinations, a hybrid motor uses solid fuel and liquid oxidizer.
Today’s test of a flight equivalent 30 kN hybrid motor demonstrated ignition and sustained combustion for the intended duration of 15 seconds. The motor performance was satisfactory.
The use of liquids facilitates throttling and the control over the flow rate of LOX enables the re-start capability. While both HTPB and LOX are green, LOX is safer to handle. The hybrid motor tested today is scalable and stackable, potentially paving the way for a new propulsion system for the forthcoming launch vehicles.