Overview: The Ike Refueling Depot

The Refueling Depot plays an instrumental role in the frontier of space exploration and utilization. It has the capacity for four kerbals to live comfortably for long periods of time, with its greenhouses, inflatable quarters, and life support equipment. A hydrolysis fuel miner with an inflatable tank provides fuel for Duna orbiting vessels. The entire base was carried to Duna using the Minotaur II heavy transport.

Review: The Decommissioned Minotaur Heavy Transport System

The Minotaur I was designed as an interplanetary transport vehicle with 12500 m/s of delta V. It contained a standard payload of two hybrid rovers and two detachable habitation modules, shown below. 16 extra docking ports allowed for satellite piggybacking, refueling missions, and mission versatility. The whole system weighed over 210 metric tons.

Features:

• Hybrid Rovers: The two rovers had a delta v of 4000 m/s, enough to land and conduct Single-Stage-to-Orbit launches over Duna and less massive bodies. They contained AI navigation and maneuver systems, in addition to life support and capacity for two kerbals each. 

• Detachable Habitation Modules: These modules are designed for landing on planetary bodies to bring personnel to extra-planetary bases. While attached to the transport, they serve as 1-g artificial gravity areas when transport roll is induced using  RCS. This artificial gravity is essential for maintaining health on long term missions. The habitation modules contained propulsion systems with 5000 m/s of delta V, in the event of an emergency return to Kerbin. The heavy duty design allows for re-entry into Kerbin's atmosphere. Advanced life support systems, cyro-sleep modules, and luxury quarters make the living space enjoyable. 

• Propulsion: Two LV-N atomic rocket motors mounted bilaterally at the aft end give a slight 0.5 m/s² acceleration over a long period of time to achieve up to 12500 m/s delta-v at 120 kN of thrust.

• Energy: The transport used four huge extended solar arrays for maintaining life support and equipment during the mission. While in transit, the ship was rotated to face Kerbol using RCS in order to keep the panels oriented to the light.

Modifications:

A later model, the Minotaur II, was made with three LV-N rocket motors and inflatable fuel tanks for better efficiency and thrust, shown below.

The Minotaur III was designed as a replacement for the Minotaur II. It had the same delta-v with a much smaller moment of inertia during maneuvers. In addition, it contained four LV-N atomic engines instead, for quicker burns at 240 kN of thrust (1 m/s² of acceleration). Shown below is a configuration for a base deployment mission over Duna which supplied all the habitation modules for the Ike Refueling Depot.

Below are Kronal blueprints for a simpler design of the Minotaur III, with a hydrolysis fuel miner in the payload.

Decommission:

The Minotaur was decommissioned due to its large maintenance costs and maneuvering difficulties due to its large moment of inertia and low thrust.