Artemis & Persephone - Kerbin SOI, Apollo Mission Profile

Boots · February 10, 2016

Below is a development history of my 'Artemis' kerballed rocket, for use in the Artemis (Mun) and Persephone (Minmus) missions.

Mods used in construction:

- Universal Storage

- DMagic's Orbital Science

- Taurus HCV

- USI-LS

- CTT is also in effect, hence part choices

Artemis Mk. I

Crew: 1

Weight: 104.6t

Cost: √ 54,624

Mission profile: Direct ascent (no Munar/Minmar descent stage)

Missions: Artemis I

After the lobbing of unkerballed space drones towards every ball of rock in Kerbal's SoI, and a few unkerballed "impact" missions to Mun which had been downgraded on the fly from 'controlled landing' after several failed attempts, the KSC insigated the Artemis program - an attempt to land and return a single Kerbal from Mun as a publicity stunt for further funding. The Artemis I's "custom" (read: cobbled together) lifter used the underpowerwed "Skipper" as an ascent stage, the development of the "Mainsail" having stalled from lack of funding. The "Poodle," initially intended as a return stage for the original Artemis design, powered the transfer stage. To help the underpowered craft into orbit, four BACC SRBs were attached to the ascent stage. The Mk 1-2 pod provided control and life support, despite having been designed for a maximum of one day's orbital flight in LKO for the Castor & Pollux rendevous missions. A rudimentary science package was welded to the bottom of the pod, and the heatshield attached underneath this assembly. This was then mouned on a descent/ascent stage - an oversized fuel tank (producing drag-related headaches on ascent) and four tiny lander legs designed for use in the unkerballed Munar lander program. The primitive craft lacked even a radio antennae - a flaw not corrected until the current Mk IV. A small package of emergency chocolate was included in case of catastophic morale collapse. Valentina Kerman endured cramped conditions, G-forces well beyond the pod's rating, and constant concern at the underpowered and under-engineered componentry, successfully piloting the ramshackle contraption into Munar orbit, making Munfall and returning unscathed.

Artemis Mk. II

Crew: 1

Weight: 119.3t

Cost: √ 72,000

Mission profile: Direct ascent (no Munar/Minmar descent stage)

Missions: Artemis II

The accolades (and, more importantly, funding) that followed the Artemis I landing paved the way for the development of the Artemis Mk II. Though it retained the mission profile and "organic design" of the Mk I, improvements to the craft were comprehensive. A brand new, custom-built lifter took advantage fo the new "Mainsail" heavy lifting engine, allowing for a considerable fuel increase to power the new, heavier transfer stage. The "Skipper" moved to that transfer stage. After some frightening moments involving the unstable Mk. I lander, the landing legs were increased in durability and RCS thrusters provided for landing (though they were not used on the Artemis II mission). An on-board flight computer was added, though no radio antennae. The emergency chocolate was retained. Jebediah Kerman piloted Artemis II to a successful Munfall and return.

Artemis Mk. III

Crew: 3

Weight: 270.2t

Cost: √ 124,855

Mission profile: Munar/Minmar orbit rendezvous

Missions: Artemis III (aborted landing) & IV, Persephone I, II & III

Even before the production of the single instance of the Mk II, the Mk III was already in the final stages of design. Anticipating further funding, the KSC had turned its attention to delivering a trained scientist to the Munar surface, in order to increase the data yields from future Artemis missions. Gene Kerman also set his sights on Minmus, planning several Persephone missions with the new spacecraft. The added weight of two kerbals and a considerable upgrade to the science package meant a change in mission profile to a rendezvous in Munar (or Minmar) orbit, which necessitated the construction of a new command module and separate lander. The new, mission-specific lifter rose on one "Mainsail" and four "Skippers," the latter progressively discarded through the ascent. The transfer stage presented a challenge - the larger-diameter and higher-volume fuel tanks were not yet ready, nor were the larger-diameter fairings. The solution was to weld four crudely streamlined 1.25m tanks to the side of a 2.5m tank. This "design" - which recalled the primitive methods behind the construction of the Mk. I - powered the bulk of the Artemis and Persephone missions. The new lander had an LFO-powered descent module on the venerable LV-909, and two "Puff" monoprop-powered ascent engines. Most of the weight of the Munar/Minmar ascent stage was monoprop, with five separate spherical tanks attached wherever they could fit without threatening the flight dynamics of the craft. The command/return stage was a rudimentary design, lacking a flight computer, snacks, or comms equipment. The rationale was that the lander's radio mast would suffice until it was discarded in Munar/Minmar orbit, at which point the crew were basically home anyway, so what were they complaining about?

Though a workhorse of the KSC's Kerbin SoI program, the Mk. III was not without its flaws. The shakedown mission - Artemis III - was a failure. Only once the craft was in Munar orbit did Mission Control realise that the factory had installed a 1.25m tank instead of the specified 2.5m tank. With insufficient dV to make Munfall, the mission was scrapped and the crew retuned home empty-handed. The minimal science package underwent several upgrades during the operational life of the Mk. III. With the Munar/Minmar descent stage proving overpowered once the correct fuel tank was installed, several instruments were added to it - by the end of its life, these included a thermometer, barometer, magnetometer and laser soil ablator in addition to the materials bay and goo container. Though the final ascent stage had worryingly small thrust and a very small monoprop reserve envelope in Munar flight, when used for the Persephone missions, the Mk. III truly came into its own. After the failed Mun mission, the Mk. III powered three Minmus landings in quick succession. Data (and more importantly, funding) begane to pour into KSC.

Artemis Mk. IV

Crew: 3

Weight: 376.8t

Cost: √ 194,670

Mission profile: Munar/Minmar orbit rendezvous

Missions: Persephone IV, Artemis V (in progress)

Built around the new heavy-lifting Kerbodyne KR-2L "Rhino" ascent motor and the R&S Capsuledyne "Quadroodle" transfer motor, the state-of-the-art Mk. IV is the culmination of the Artemis program. Delivery of the high-volume tanks and 3.125m fairing planned as far back as the Mk. II enable high thrust and long burn times. Changes to the lander and command/return stage have been minor, and are mostly creature comforts and mission-specific science loadouts. The command/return module has a new antenna and flight computer, as well as a streamlined and shielded docking port. The lander's ascent fuel loadout has been rationalised into two of the new cylindrical monoprop tanks, increasing the safety envelope for Munar operations. It also has a new high-gain antenna to replace the whip antenna of the Mk. III. The current science package swaps out the Magnetometer for a seismic sensor, to finally answer the question of Minmus' celestial interior: sherbert, or jelly?

The Mk. IV means that the next stage of KSC operations can begin: Persephone IV and Artemis V are designed to routinse space travel, allowing for high crew rotation and the building up of crew experience - especially the engineering corps - ahead of the planned Ares missions to Duna. With the Mk IV, the KSC Artemis and Persephone programs have finally come into their own. The Mk. IV is truly the harbinger of the new era.

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