Manned Jool survey

[DMagic]

After setting up a base and communications relay around Laythe I decided to conduct a manned survey of the other Jool moons. I'm planning on making a single carrier ship to ferry landers for the 4 other moons. Landers for Pol, Bop, and Vall were designed based on, um, ground-based observations of the Jool moons, but I decided I needed to take a closer look at Tylo and its massive gravity well before finalizing my lander for that moon. I'll try to stitch together some of my images to avoid putting up unnecessarily long posts.

Here is my Laythe base, Quad-Mega Base 2.0, which will be conducting operations on the Jool side of things.

This is the launcher and a shot of the probes sent to Tylo.

The less said about the ill-fated lander the better, but the orbital Sat-Map probe, visible underneath the lander, worked fine. I was able to map everything up to about 70 degrees north/south of the equator.

My next lander design worked out much better. As expected mechjeb failed miserably at landing, running out of fuel about 500m above the surface. But I was able to bring it down myself with plenty to spare. I landed at a fairly high region, about 8km up, using about 3000m/s of delta-v.

With this information in hand I finalized my Tylo lander design and finished launching the components of my mission. From left to right, we have the core vehicle, Endurance, the identical Bop/Pol landers, the mid-sized Vall vehicle, and the heavy lander for Tylo.

Rendezvous and orbital refueling took place at my Minmus orbital fuel station. Most of the mod parts come from the Kosmos pack, with a few fuel tanks from KW, radial engines and command pods from HOME, and a few Sat-Map probes. The assembled vehicle is about 225 tons, made up of 364 parts, with a crew of 11 Kerbals, and a total of 16 different crafts, including the core carrier, and the landers, rovers and probes.

This picture clearly shows that I'm a no-talent hack, who just threw together some parts and clicked the 'fly-mission' button. Or, no, I mean it shows my exit from Minmus, and shows the flaw that should be obvious from the previous picture, that my vessel is severely unbalanced. The heavy Tylo lander is about 75 tons, while the Vall lander is only 45 tons, meaning the whole thing will pull towards the heavier side. With a full fuel load and no way to balance things out or set engines at different throttle levels, I have to use the Vall booster engine to adjust my heading. Activating and deactivating it allows me to, more or less, stay on course, but it's pretty tedious.

Once I got back down to lower Kerbin orbit I activated the radial engines to take as much advantage of my high velocity as possible. I still had to play around with balancing thrust levels, but it wasn't quite so bad at this point. After a few minutes of this I deactivated all but the 3 nuclear engines and carried out the rest of the burn, and I was able to finally balance the load enough to stay on target and successfully set up a Jool encounter.

Another crucially important bit of information that I learned, which in retrospect should have been head-slappingly obvious, during these burns, was that the amount of delta-v required to move from a moon, back to a low orbit of the the planet is only slightly more than what's necessary to break orbit around the moon. I had been thinking that returning from a moon to a low orbit around the planet would take a delta-v equal to that required to get to the moon in the first place. Which is of course, dumb; that's what it would take to get back to low orbit, and then circularize my orbit at that point. So all of my landers were designed with 1000-1500 m/s of extra delta-v that I was planning on using to get from the outer moons down to a Laythe orbit. So this should simplify some things, allowing me to set up encounters of Bop and Pol, the two small, highly inclined, moons without dragging the whole vehicle along for the ride, and maybe ensure that I actually have enough fuel for the return trip. It's amazing how many things there are to learn after 200 hours of playing.

Next up I have to optimize my Jool encounter, launch some of the initial probes, and figure out the ideal way to launch and set up encounters for the Bop and Pol landers.

[DMagic]

Now that I'm on my way to Jool we can take a closer look at the different components of my spacecraft. Here is the core module and one of the light Pol/Bop landers. You can see that the core is very simple, just a fuel tank and a big engine (that's the nuclear engine from the Kosmos pack, I used it just because I like the way it looks, it is no more powerful than the regular engine and it weighs a lot more). The trusses are actually very stable when accelerating, with just a little bit of flexing at the docking ports for the heavier landers. The big RCS thruster on top helps with turning and stabilizing the craft.

On the right is the light lander, which is actually made up of four separate crafts. On the bottom is an extra fuel tank used to refuel the core stage after the transfer burn to Jool. This will be released with a few L of fuel and set to plunge into Jool, one on as steep a descent as possible, and the other on a bit of a slower path. On top there are two small probes that will be released upon achieving orbit around Pol/Bop. One is a small Sat Map probe with enough fuel to set up a wide, polar orbit. The other is a small lander that will be used to scout out possible sites for the manned lander. In the center we have the lander itself, with fuel enough to line up my orbit with the target, land, take off again, and meet with the carrier back in Laythe orbit, this time a lot lighter, with many fewer parts.

Here we have the mid sized Vall lander, and the heavy Tylo lander. The Vall craft has the same two probes on top, the lander has a bit more fuel to compensate for Vall's much higher mass. The landing struts on the radial tanks give the small lander plenty of clearance, so it will be deployed after landing with the radial engines. The lander can then blast off again and meet up with the carrier.

The Tylo lander doesn't have any Sat Map or lander probes, since I already launched those, but it does have a small Jool relay probe on top. This will be released during the transit to Jool and should arrive several days ahead of the other craft to act as a communications relay in high Jool orbit. It carries another rover on the bottom which will be released upon landing. The tall, radial fuel tank stacks will only be used for the descent stage, dropping off before the final landing. The radial engines are only there to give the final boost necessary for landing, and the first stage of take off. The central, nuclear engine should be able to finish getting the craft into orbit and to get back to the carrier around Laythe. Neither of these two ships have RCS thrusters on the final stages, so docking should be tricky, but doable. I found that a stack of I-beams work great when you need to have a really long ladder.

The first Jool probes and the communications relay are released after setting up a reasonably close encounter with Jool. They are each set to arrive about a day apart from each other, and about 5 days ahead of the main craft.

Just after reaching the Jool system I released the Bop and Pol landers. This far out they can perform most of the inclination change necessary to reach their targets without spending much fuel. This lets me keep the main craft on an almost flat inclination for the initial approach to Jool.

This is what I call orbital spaghetti. The two probes are set to crash into Jool, while the relay probe arcs behind the planet in a highly inclined path. The two landers are at an inclination that will let them meet up with Pol and Bop, the orbits of which can be seen along the top. One of the landers looks like it will have a glancing encounter with Laythe, but it doesn't seem like it will have much of an effect. The three main craft are all set to aerobrake around 30 minutes apart, so I'll have to be careful about the timing.

The two probes meet their inevitable demise, quickly at first, and then slowly, as they drift down in the increasingly dense atmosphere of Jool. The probe on the direct descent peaked at over 190 g's, while the probe on the more gradual path 'only' reached around 80 g's, valuable information for someone, I'm sure.

The relay had a harrowing trip through the upper atmosphere but made it through alright. Laythe, Tylo, Vall, Pol, and Kerbol were all aligned during this stage, though you can only really see Laythe here.

Up next I'll set up my initial encounters with the moons, map out the targets to determine suitable landing sites, and begin exploring.

[DMagic]

After entering the system it was time to set up aerobraking nodes at Jool to get all three crafts into orbits intersecting their respective targets. The main craft came in at an altitude sufficient to put me into an orbit intersecting that of Tylo's.

I must have had lucky timing, because I managed to successfully intercept Bop and Tylo on the first orbit. The heavy lander was released from the carrier and achieved a stable orbit around Tylo.

And here, the light, Bop lander came in for a somewhat disconcertingly close approach while burning for orbital insertion. I kept my periapsis above 18 km, but I still passed barely 1km over some of those mountains; be careful around Bop. After getting into orbit I released the Sat Map probe and put it into a nearly polar orbit.

After releasing the heavy lander at Tylo, the Endurance carrier went in for another round of aerobraking to set up orbit around Vall, this was made somewhat difficult by how severely unbalanced the craft was, but it worked out okay in the end. After just 2 orbits I met up with Vall, released the lander, and completed a Sat Map survey of the surface.

The orbital map looks a little more civilized now, with just the Pol lander and the carrier left in Jool orbit.

And after a few more rounds over Jool I made it into Laythe orbit, although I somewhat stupidly ended up in a retrograde orbit, but that shouldn't make too much of a difference. Here the carrier orbits over Laythe, passing just above my base situated on the eastern edge of the crater lake seen at the bottom of this picture.

Back at Bop something interesting occurred. After completing the Sat Map survey of the surface, an anomaly was detected in the northern polar region. Due to the high inclination required to reach the target, it was decided to send in the lander probe so as to not waste too much fuel altering the main lander's orbit.

All telemetry was nominal as the lander passed over the treacherous terrain on its initial approach.

As the probe approached the anomaly, the data stream became increasingly intermittent. What follows is a series of increasingly distorted images, as disturbing as they are fascinating. From a distance it's not clear what is being seen, but as the probe continues closer it becomes apparent that the object is not an entirely natural occurrence.

On closer inspection the object appears to be of biological nature, but exhibits no signs of activity. At this point the data stream from the probe becomes increasingly erratic; unexplainable gravitational distortions and electromagnetic interference are recorded.

The automated probe software proceeds with solar panel deployment after landing, at which point all of the probe's instruments record signals above their maximum tolerances. A single image is transmitted before all communications are lost.

The crew of the Bop lander report their findings to the mission commanders. Analysts at the Laythe base command post, however, report receiving nothing unusual from the data transmitted via Jool Relay 1. The decision is made to carry on with the landing at Bop, though as a precaution the craft will set down in the southern region of the moon, well away from the anomaly...

[DMagic]

As we continue with the mission, our intrepid Bop crew begin their descent to the surface. The landing site is a small valley just south of the equator.

After a successful landing the crew is excited to get out of their cramped lander can and explore the area.

However, as Bop Mission Commander Grezgor Kerman is occupied collecting samples, Mission Specialist Jenby Kerman begins behaving erratically. He starts wandering off towards the northern polar region of the moon and can be heard over the comm link repeatedly whispering "I just need to get a little higher." Commander Grezgor is forced to track down Specialist Jenby and escort him back to the lander.

The decision is made to return to orbit immediately.

Meanwhile, the Pol crew has successfully arranged an encounter with the moon during their second orbit of Jool. After burning for orbital insertion around the strangely colored moon they release the Sat Map probe, which changes its orbit to a polar inclination to survey the surface.

No anomalies are detected on Pol, however, an interesting geological formation is identified that could be the remains of a large impact crater. The lander probe is released and prepares to set down in the crater.

The probe descends to the surface, while Jool and its inner moons rise, with Kerbol in the distance.

Closer to the surface, several strange formations are seen on the crater floor.

The Pol crew decide to land in the same region to study these formations. After a rather rough landing, the spacecraft comes to a stop, and the crew prepares for EVA.

The crew are excited to be outside, and take a moment to enjoy the spectacular view.

They take a closer look at one of the formations, which they have taken to calling Pol Hoodoos. Mission Specialist Ludzon Kerman manually inspects the probe and recovers data from its instruments.

After a successful Pol EVA the crew prepares for ascent. As they fly over the surface they note some truly fascinating terrain features.

Next up the crews of the Vall and Tylo landers prepare for their descents.

[DMagic]

The crew of the Tylo lander, having identified a landing site, begin their descent to the surface. Tylo is the heaviest moon in the solar system and has no atmosphere, requiring over 3000 m/s for landing and ascent. After a rather harrowing initial descent, the crew bring the ship in for a relatively soft landing.

Soft, but not quite soft enough. The lander came down intact, there was a little bit of worrisome flexing of the radial fuel tanks, but it turned out okay. The rover didn't come through so well though, it lost a few wheels and its main solar array. Thankfully Mission Commander Kenzer Kerman is able to repair the damaged wheels, and the auxiliary solar panels provide enough power to run the rover.

The crew poses for a picture.

The landing was a little off target, so the rover sets out to investigate the anomaly detected nearby. From the ground, nothing out of the ordinary is discovered. However, the orbital Sat Map probe acquired this image from above. Opinions remain divided as to what, exactly, this means. Mission Specialist Neweny Kerman maintains that "those commie jokers must have got here first."

After a successful EVA on the surface of Tylo the crew prepares to leave.

Through some careful fuel management, and tricky ascent maneuvers, the crew is a able to successfully regain orbit around Tylo. After starting their descent with a 65 ton vehicle, they are left in orbit with just under 6 tons of total mass.

Meanwhile, the crew of the Vall lander, having identified an anomaly in the southern region of the moon, release the probe lander.

Initially, nothing unusual is observed, however, as the probe approaches the anomaly, its sensitive cameras pick up an intense emission of dangerous, short-wave UV radiation. The brightness of the anomaly prevents the probe from capturing a clear image.

The crew decide to land a safe distance away from the anomaly.

The crew step out into the fading light to prepare the rover for its trip and study the surrounding area.

Using the rover's more sophisticated cameras, the intense UV radiation can be filtered out, allowing for a clear view of the anomaly. After approaching the area, this strange, and most certainly unnatural formation is observed. More disturbingly, the probe lander has inexplicably moved several kilometers away from its initial landing site. The lander was low on fuel when it set down, how it was moved so far remains unknown.

These images of the structure are transmitted from the rover to the crew. The objects are seemingly inert, the crew however, reports an increasingly foreboding sense of dread.

They take one last look towards the structure before climbing back into the lander for take off, eager to be away from the planet's surface.

They blast off from the surface, separating the radial tanks, leaving only the main engine to carry them away.

When passing over the anomaly the crew can clearly see how far apart the rover, still at the structure, and the probe have become. Rather than ponder how this could happen they turn away to prepare for the final orbital maneuvers as Jool rises over the surface, with Laythe hanging in the sky nearby.

Next, the final phase of the mission begins, as the landers return to the Endurance in Laythe orbit and prepare for the trip back to Kerbin.

Edited December 4, 2013 by DMagic

[rryy]

~snips~

They take a closer look at one of the formations, which they have taken to calling Pol Hoodoos. Mission Specialist Ludzon Kerman manually inspects the probe and recovers data from its instruments.

~snips

I believe they should be called Pooloos.

[DMagic]

The lander crews plot their return trajectories and burn for a capture at Laythe orbit.

Here the orbits of three landers are plotted for their return to Laythe.

And one by one they re-dock to the Endurance. Everything's a little smaller than the last time they wore docked together.

During the mission it became apparent that there would not be enough fuel for the return to Kerbin. Even after jettisoning some of the dead mass they would come up about 500 m/s of delta-v short of what is necessary for return. With that in mind a refueler mission was launched.

The refueler's mission plan called for landing at the Laythe base. Things didn't quite go according to plan however. The crew overshot the base by about 20km and came in a little too fast. Everyone survived alright though, if a bit irradiated. And they can make the trip to Laythe base on foot.

With sufficient fuel the trip back to Kerbin begins. The first burn sets up an escape from Laythe orbit back down to a lower orbit around Jool.

Endurance burns for home around Jool, and with a small correction burn later on, plots a course for an encounter with Kerbin.

Tragedy struck as they passed the orbits of Jool's outer moons. Bop lander Mission Specialist Neweny Kerman, who had been restrained ever since the ill-fated Bop landing, broke free and exited the ship. As the crew looked on helplessly he used his EVA pack to return to Bop, apparently not realizing that he could never overcome his current orbital velocity, taking him outside of the Jool system. He could be heard over the radio excitedly shouting that he was "coming home..." Radio contact was soon lost, his EVA transponder shows him on an elliptical orbit around the sun, though perhaps someday he will end up back on Bop.

While the Endurance makes its return trip from Jool, the crew return vehicle is launched. It will await the crew in orbit and return to KSC.

After a long trip back the crew finally make it to Kerbin orbit, ready to return to the surface. Just over 3500 m/s of delta-v was required for the return, from Laythe orbit, to Jool, and back to Kerbin.

They meet the crew return vehicle in orbit, transferring all but the Endurance pilot, and releasing the landers to burn up in Kerbin's atmosphere.

While the crew returns to the surface, pilot Edley Kerman takes the Endurance back to Minmus orbit.

There he docks at the Minmus orbital refueling station, ready for another mission.

The crew return vehicle begins its descent, approaching KSC from the west and gently setting down just past the launch pad.

Home at last. The crew exit the return vehicle and set foot back on Kerbin after a successful mission to all of Jool's moons.

That was fun. It was 10 launches, for a total of 11 probes, 2 rovers, 4 landers, 1 refueler, 1 crew return vehicle, and 1 carrier, 20 spacecraft in all. It took a lot of planning, and a few screw ups, but it worked pretty well in the end.

[jordanjay29]

I just found your topic and I was completely entranced as I read. What an excellent adventure, and superb storytelling. I have yet to venture beyond Kerbin orbit, but this makes me both excited and terrified to do so. I'm not sure I'm ambitious enough to try to land on all four moons.

[FlamedSteak]

Dude that is epic.

[Specialist290]

Nicely done, especially the Tylo lander!

[DMagic]

Nicely done, especially the Tylo lander!

Thanks, but the Tylo lander could use a redesign. Everything else worked fine on the first attempt, no reloads, but that Tylo lander took about 15 tries. It just doesn't have enough TWR so landing burns way more fuel than it should, and the landing struts block the radial engines. I really like the overall design though, I think maybe some slightly bigger engines on the bottom of the radial tanks could improve it a lot.

Edit: Anyone know how to get this thread moved to mission reports? Spacecraft exchange doesn't really seem like the right place for it. I can share .craft files if anyone is interested though.

Edit: Thanks for moving this

Edited May 27, 2013 by DMagic