Duna Explorer - slightly overkill

[Soda Popinski]

Way back in KSP 0.22, after landing a mission on Duna in vanilla KSP, I installed a bunch of mods, and restarted career mode. Here's the mission I sent to Duna, prior to my Discovery 2 mission to Jool.

Mods used: Ferram Aerospace Research, Kerbal Isp Difficulty Scaler, Kerbal Joint Reinforcement, Deadly Reentry Continued, Remote Tech 2, Engineer Redux, Docking Port Alignment Indicator, Kerbal Alarm Clock, Procedural Fairings, RealChute, ScanSat, and Kerbal Attachment System.

The Background:

After the recent development of Kethane refining, it was decided to send a mission to Duna, and see if we could successfully mine kethane and produce enough fuel to get back. This would serve as a test bed for later missions, such as the proposed Project Discovery to Jool. The newly developed NERVA rocket engines would be utilized for this first interplanetary journey. Instead of building a single ship, why not build 2 for the price of 2. Between these sister ships, a fuel tanker and mobile kethane drill rig & refinery would be attached. The refinery will produce fuel, and it and it's personnel will remain behind for future refueling missions.

The Mission:

As kethane mining is a new technology, a prototype tanker and kethane mining / refining rig will be sent to Minmus after mapping surface kethane stores.

Once the final version of the kethane rig & tanker are assembled in orbit, the sister ships, Phobos and Deimos will be sent up to rendezvous and dock with the tanker to form the Duna Explorer mission. Once fully fueled in a 165 km circular orbit from the IGS (International Gas Station), the Duna Explorer will embark on the first available launch window on year 1, day 58, as determined by the KSP Launch Window Calculator..

After a 67 day journey, the Duna Explorer will perform aerobraking maneuvers at 15,000 meters over Duna. Once in orbit, the Kethane Rig & Tanker will separate and head to Duna's mun, Ike and begin scan for, then mine kethane. Deimos will follow to Ike performing scientific sensor studies along the way. Meanwhile Phobos will separate its lander, which will aerobrake in Duna's atmosphere, and soft land with use of parachutes. Deimos will do the same at Ike, without the advantage of atmospheric based re-entry and descent (all rocket powered).

Ascent stages of the landers will rejoin their respective ships, which will rendezvous and dock, refuel, then return to Kerbin. The refinery along with 4 Kerbals will remain to provide a fuel depot.

Mission updates:

Final fuel/RCS tanker with attached command section, mobile kethane drill & refinery, along with satellite probe with long range uplink antenna, ScanSat radar and Kethane detection equipment.

Phobos Ship with crew of 3.

Orbital docking of Deimos to rest of Duna Explorer.

Completed Duna Explorer with a total curb mass of 196.94t. She carries 72 tons of liquid fuel / oxidizer, totaling 3571 m/s delta-V. Delta-V calculations call for 1007 m/s to initiate Hohmann transfer for Duna intercept, and assuming efficient aerobraking, only 642 m/s required to return to Kerbin. We may have gone a little overboard.

The fully crewed Duna Explorer on its way to the Red Planet.

Edited January 8, 2014 by Soda Popinski

[Soda Popinski]

Mission Update:

Just days prior to launch window, a piece of debris was spotted floating near the Duna Explorer. It turned out to be rover wheel. Inspection determined it came off the Phobos rover, where it came in near contact with the ballute inflatable heat shield. Old cookey (Macmy) insisted it was the "Space Kraken," an old wive's tale spacer's often talk about. Mission control determined the ballute should probably have been attached a little further away, possibly with a girder in between - a design flaw. It was determined it would be too much trouble to launch a new lander / rover module, and that Wehrman Kerman, Duna Rover Driver would just have to make due with 3 wheels or walk.

We went ahead and launched on year 1, day 58 with an approximately 1000 m/s burn to Kerbin's prograde.

This episode precipitated several inspections and simulations to make sure everything works out well. Better check for design flaws. Almost everything else in the ship had already been tested prior to launch: kethane rig, ballute heat shield coverage, lander, docking and undocking, RemoteTech control of the probe and autonomous Kethane drill / refinery...everything except the communications system since we were still in LKO.

So, lets fold out that fancy long range antenna...in simulation (*cough*F5 / F9 *cough*)

Luckily, we have the secondary long range uplink antenna on the probe.

Also showing the results from extreme aerobraking simulations using Kerbin's thicker atmosphere.

Note: Both Deadly Reentry Continued and Ferram Aerospace Research are installed. This necessitated placing the large folding antenna (needed for RemoteTech2) in an aerodynamically shielded area during lift-off. Hence having it tucked behind a structural fuselage. The ballute heat shields were needed to survive aerobraking and reentry (for the lander).

Edited January 8, 2014 by Soda Popinski

[Soda Popinski]

After almost 70 days, the Duna Explorer arrived at the red planet. Preparations were made for aerobraking.

It worked in 2010: The Year We Make Contact. I was hoping it would be as dramatic as in that movie...

It wasn't

[Soda Popinski]

I don't have a lot of screen shots of these next sequences.

After orbital insertion, the Duna Explorer was broken down to the Phobos for Duna, Deimos for Ike exploration, and Kethane Rig to find, mine, and bring back fuel from Ike. The Kethane Rig was placed into transikal orbit for intercept via the poodle engine exposed after jettisoning the ballute.

The probe atop the Kethane Rig was separated en route, and adjusted to enter a polar orbit, with a little bit of extra prograde delta-V to allow it to arrive early.

This proved to be tricky, as the crew found commands sent to the probe did NOTHING. For about 3 minutes, at which point the probe would move. It dawned on the crew that radio signals were being beamed from Kerbin and moving at only 300,000 km/s (RemoteTech2). This time delay made orbital maneuvers rather tricky. Part of the reason there were 6 kerbins in the Kethane Rig was because it was believed this would allow the spacecraft to command probes. Apparently Mission Commander Rodton didn't read the RemoteTech2 instructions very well. This function would require the large probe core, which would later be integrated into the next generation ship, Discovery 2.

Eventually the probe was put into orbit, but not a very pretty one, and kethane deposits were found. The Kethane Rig landed, Kethane Drill/Refinery separated, and landed next to the tanker for mining commence. This was no mean feat, as the Automated Kethane Drill / Refinery was unmanned, and also probe controlled. As a 3 minute delay would be impossible to work with when trying to delicately maneuver while dealing with surface gravity, a physical link using Kerbal Attachment System was used to allow direct control of the Refinery section from the manned tanker (all tanker torque and RCS deactivated).

Meanwhile, science had to go on with the Phobos and Deimos landers.

To which Chef Macmy and Sous-chef Oddard on the Kethane Rig replied, "Say what?"

[Soda Popinski]

After enough sciencing, it finally came time to bring the lander crews back

The return launch window to Kerbin was in 148 days. During the intervening period, KSC engineers working on the Discovery 2 perfected the fully automated Mobile Kethane Extractor Refinery Tanker (MKERT). As such, and in part due to complaints from Macmy and Oddard (who didn't read the fine print of their contract), it was decided to bring back the fuel tanker along with the rest of kethane rig crew originally slated to stay behind. Besides, the rest of the return crew realized no Chef Macmy and Sous-chef Oddard, no snacks besides rehydrated rations.

After 2 trips of the Fuel Tanker, the Duna Explorer was reassembled, sans sections of the lander no longer needed nor the Kethane Drill Refinery. The original plan did NOT include the return of the Kethane Rig, and hence no 2nd ballute heat shield was sent with the craft. It was decided to leave one of the Kethane Descent stages in place (Poodle rocket + fuel tank) to act as a heat shield.

On year 1, day 274, a 642 m/s burn was performed to place the Duna Explorer on a Hohmann transfer for Kerbin intercept. This was quite stressful back at Mission Control, as it overlapped with preparations for the the year 1 day 282 launch window for the newly constructed Discovery 2's launch window to Jool.

While this was happening, Kerbal Space Program 0.23 came out. While switching over to this, due to some incompatibilities with mods, there were numerous Kraken attacks. The Duna Explorer itself exploded during docking procedures, but due to saved games, and some tweaking of the order of docking, it was saved. The International Gas Station on the other hand could not be saved, and would explode into many, many pieces whenever it was loaded. So a new similar space station was put up at 100 km LKO. The original IGS was at 165 to reduce processor stress, and increase FPS, as Kerbin's surface isn't fully rendered at that altitude.

While en route back to Kerbin, our first Single Stage to Orbit shuttle, using the newly developed Hybrid RAPIER engines. It's unwieldy, not very sexy, and it uses a hybrid engine design. We christened it, "Shuttle Prius." It was successfully launched with the crew for the Jool Mission, and after crewing the Discovery 2, rendezvoused with and docked to the new Firefly Space Station, and will serve as a crew return vehicle for the Duna Explorer, as it's not capable of land fall (at least not on purpose).

After 67 days, the Duna Explorer made its triumphant return to Kerbin space. Even though there was PLENTY of fuel left since the tanker was brought back, it was decided to go ahead with aerocapture in Kerbin's atmosphere. Mission Commander Rodton insisted, "It's the principle!" We'll see if the Kethane Rig's McGuyvered heat shield will stand up to Kerbin's atmosphere.

Just in case, a shallow aerobrake maneuver (~38km IIRC) was used, with 4 or 5 dips into the atmosphere to gradually reduce speed and put the Duna Explorer into a Low Kerbal Orbit for rendezvous with the new Firefly Space Station.

Docked. Welcome back guys.

Edited January 11, 2014 by Soda Popinski

[Commander Zoom]

Great thread!

And your choice of caption font make me feel like I'm playing THE DIG again... (Commander Boston Kerman, anyone?)

Oh, and which mod do those ballutes come from?

Edited January 11, 2014 by Commander Zoom

[Soda Popinski]

Great thread!

And your choice of caption font make me feel like I'm playing THE DIG again... (Commander Boston Kerman, anyone?)

Oh, and which mod do those ballutes come from?

Thanks for reading! The font is "Commodore 64." The mod comes from Deadly Re-entry Continued. Speaking of which, I have the final update - re-entry.

[Soda Popinski]

Now that the crew has safely returned to LKO, time to put that spanking new shuttle to use. First get the entire 12 man crew to EVA over. Lt. Jedlorf Kerman will be piloting again.

Desfen asked Jedlorf, "How many drops is this for you, lieutenant?"

"38...simulated."

After separating from the station, a retrograde burn was performed to place periapsis at 35km directly of KSC.

The Shuttle Prius was then put into a high pitch attitude to increase atmospheric drag as much as possible while still in the upper atmosphere.

"Express elevator going to hell. Going down!"

Welcome back to kerba firma. Our heroes will forever be remembered as the first kerbals to visit another planet. The Duna Explorer will remain in orbit, as a museum and legacy to the brave kerbals who almost went without snacks to go where no kerbal has gone before.

[Collin Dow]

Damn, those are some impressive ships, and a fun and interesting write-up!

[Soda Popinski]

Thanks for the kind words. Someday, I hope to figure out how to land that spaceplane. So far, both times I've landed it at KSC (without destroying it completely), I've always knocked the center engines off. I might have to move the landing gear back, if I can. Too late for the one back at the space station on my Jool mission.

[Eckee]

As a RP and mothership/station sucker myself, these are amazing. I like your taste on spacecrafts.

[Soda Popinski]

Quite the blast from the past.  Technically, I'm still playing this save-game.  It's the same one I'm currently doing a big rescue mission for.  Check my sig to see the mission report / cinematic if you like seeing my builds.  I'm taking a little break right now.
 

You might get a kick out of my current space station in 1.2.  The main station consists of an MSL, Hitchhiker, MKS Akaedemy, MKS Power Unit, various life support parts.  Currently there's a crappy SSTO attached, 2 nuklear tugs, an RCS tug, 2 tankers, and the new Munar orbital station (contract), docked to pick up personnel and get a tug to Munar orbit.