Minotaur IV version
Minotaur IV Minotaur IV+
The higher-performance Minotaur IV: it keeps the three Peacekeeper-derived stages and replaces the Orion 38 fourth stage with a Star 48BV motor, adding roughly 200 kg of low-orbit payload or reaching higher elliptical orbits.
- September 27, 2011
- First launch
- 1,837 kg
- LEO capacity
- No
- Reusable
History
What changes
The Minotaur IV+ shares its first three stages entirely with the Minotaur IV, all derived from retired Peacekeeper missiles. The difference is at the top: the Orion 38 gives way to a Star 48BV with more propellant, burning for 85.2 seconds at an average 68.63 kN and — unusually for the Star 48 family — offering thrust vector control.
What it buys
The swap raises low-orbit capacity to about 1,837 kg, some two hundred kilograms above the baseline, and opens up high elliptical orbits beyond the Orion 38's reach. The Star 48 family had accumulated flight experience on other launchers — Atlas V, Delta IV, the Space Shuttle and more than seventy Delta II missions — which lowered integration risk.
Basis for later versions
The IV+ was the starting point for the Minotaur V, which adds a Star 37FM stage for high-energy trajectories and has flown once, and for the Minotaur VI and VI+ concepts, which add an SR118 first stage for heavier low-orbit payloads and have never flown.