The Centipede Mission

[Kieve]

I literally joined the KSP forums to share this. It is a tale of failure and frustration, of triumph over impossible odds (and flawed engineering), and the brave but masterfully inept Kerbals who pulled it off anyway.

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Behold, the Centipede...

Weighing in at 17.16 tons, it was designed to conquer any terrain the Mun could offer up. A compliment to the newly-landed Arc Luna Outpost, it would function as a mobile command center, taking Kerbals far across the Mun in their search for more Science - without popping too many tires on the way. Perhaps sensing imminent failure, Command assigned five of the absolute dumbest Kerbals to it (and two of the smartest but most cowardly to man the science lab). Then in true Kerbal fashion, they strapped a bunch of rockets to its bumper and prepared to launch it into space. Fortunately, they'd sent up a half-dozen similar rockets under various Orbital Hauler missions and knew the OH lifter was up for the job. Then Burhat Kerman had to open his blasted mouth.

"How are you going to land it?"

The engineers promptly turned a much darker shade of green and proposed the usual solution - strap more rockets to it, of course!

Thus a set of wing-like lander cells were added to the Centipede's flanks, powered by a pair of LV-909's with two Rockomax 24-77's riding sidecar to balance Thrust between Center Of Mass. The engineers nodded their heads, pleased with their work, and certain the lander cells would do just fine. Their calculations assured everyone, on Mun the TWR was plenty high enough to ensure a safe landing!

So in went the Kerbals, and off went the rocket! Munward-ho!

Immediately, it became apparent something was wrong. The added weight of the Centipede's monstrous wheel assembly was dragging the craft down, throwing the COM badly out of alignment. This became even more noticeable as the latter stages dropped off. So the engineers went back to work, doing what they did best - more rockets! Two more 24-77's tipped the scales, keeping the Centipede finely balanced down to the last stage.

Mostly.

The trip to the Mun was a short eight-hour drift through the black, and Jeb threw them a greeting as the Centipede's crew swung into alignment behind the Mun Orbiter station. He had been exiled to the Orbiter after constantly jumping into the cockpit of anything that went towards the pad (Command finally had enough and let him go, in one mission they were quite sure would be staying put). As the Centipede prepared to de-orbit and aligned itself with Arc Luna, several things became immediately evident:

1. There was not enough fuel left in the final stage to drop the Centipede to a halt as planned. At low pass above Arc Luna, it would bleed off half the Delta-V they needed to stop. At best.
2. The engineers had misaligned the lander cells. The craft had a nasty yaw to the right, which became insurmountable above half-power.
3. You couldn't align anything with the damned gimbal! The Centipede might be pointing forward, but the lander cells faced downards (and not even straight downards). Burning retrograde had to be done blind - if orbit speed was decreasing you were pointed the right way. Probably.
4. Clearly, Command wanted them all to die, because Burhat opened his blasted mouth.

Despite the crews' assumption however, Command did not want them to die. Possibly the engineers did, but fortunately it wasn't their choice. A mad scramble ensued, as everyone tried to find a way to get the Centipede down safely, without scattering it across the surface of Mun, or popping any of those expensive tires.

When Bartbles heard the answer, he raised an eyebrow. "You're sure?"

"It's really the only way. You're one of the bravest Kerbals we know, Bart. We're sure you can pull it off."

Bartbles Kerman puffed out his chest and gripped the controls. Retrograde was already lined up and his burn was only a few minutes away.

From 45,000m above the Mun, he was going to stop them dead, and drop straight down.

The mission profile had indicated a slower parabolic descent that put them right over Arc Luna. However, every pass the Centipede had made, it picked up enormous amounts of Delta-V flying so low to the surface. The final rocket stage simply didn't have enough fuel left to bring them in safely, and it was bloody impossible to use the landing cells at the power needed to halt that kind of velocity. Every simulation (read: quicksave reload) resulted in fireballs and scattered debris being bounced back into space. Even the plentiful RCS supply wasn't going to make a dent in anything but the surface. But at lower speeds...

Thinking was not Bart's strong suit, so he tended not to do much of it. What Command told him made enough sense, and he was one of the most courageous pilots to leave Kerbin. The engines flared up, bringing orbital speed down from 500m/s to just under 200 before the tanks went dry. With a shrug, Bart cut them loose and engaged the landing cells. Sudden groans and the sound of retching filled the rear cabins as he swung the Centipede's nose down, pointing the cells retro as best as he could judge. Orbital velocity dropped even more, and slowly the altimeter counted down. 40 kilometers... 35... 30... 25. As the dials spun down, he began to believe this might actually work. It was a constant fight to keep the craft's landers aimed retro, and despite his best efforts their speed was still above 100m/s, but it was slowing, and the engines still had fuel and oh Ker I hope we don't all die!

10,000 meters. They were still dropping too fast, but speed was below 100m/s now. He kicked the engines up a little higher and the craft lurched right, yawing slowly. Pitch up, pitch down, roll left, overcompensating! Oh crud! Haul the nose back to the left. Rinse, repeat. He didn't even want to know what the back cabins must look like, though at least he couldn't hear the rest of the crew vomiting now. Some rinsing and repeating would be needed there as well, he was sure.

5,000 meters. Fuel was starting to dwindle and still they were coming in too hot. He'd lost the sweet spot, the craft was drifting all over now, and he couldn't crank the engines up any more or the yaw would become insurmountable. The Centipede's shadow danced around below them like... well, like something very drunk, Bart was much too occupied with not crashing to give it much thought right now. 4,000 meters.

Around 3,000, Bart noticed the altimeter had stalled. Whatever speed he was fighting now was pure drift. He tried to see out the window but the Cupola module had crap visibility for landing, unless it was pointed straight down. More airsick moans welled up from the rear cabin as he pitched the Centipede down again. Ah, there it was. He realigned and killed the drifting. Under 20m/s now, and dropping smoothly.

A hill rose up towards them as the craft resumed yawing. 6.5m/s. No fuel left. Their shadow was practically right under them...

With a soft bump, the Centipede touched down. Not a single tire was popped that day.

Bartbles Kerman let out a breath he hadn't realized he was holding. Apparently he'd forgotten to do that breathing thing again. Now, where was Arc Luna?

...

Aww, fish-paste!.

Edited November 5, 2017 by Kieve

[Commander Zoom]

Now this is a magnificent first post.

Congratulations, and welcome!

[Kieve]

Commander Zoom said:

Now this is a magnificent first post.

Congratulations, and welcome!

Thank you for the kind words. It took me a bit to figure out the right place to post it.

And now, to continue the journey...

The Centipede Mission: Road-Trip

Despite Bart's death-defying landing (or perhaps because of it), the rest of the Centipede's crew ousted him from the controls. For their long journey across the surface to Arc Luna, it was voted that Calger should take the controls. After all, he still had the top score on the Ker-Kart arcade machine back home - for six weeks running, so far. Secretly, Calger suspected that was one of the reasons they'd sent him off on this missions. No matter, he could fill up the leaderboards with "CAL-OWNZ" when he got back. Maybe they'd even have KK2 installed by then!

After some token protest, Bartbles relented and Calger took the Centipede's wheels. He jettisoned the lander cells and set out across the barren surface.

It didn't take long for more of the Centipede's flaws to become apparent. Despite the ridiculous number of tires, it floated and skidded across Mun's terrain like a rhinoceros on roller-skates. In fact, the only thing the hefty wheel array was good for, apparently, was draining the batteries at an absurd rate. The paltry solar panels on top couldn't hope to compensate for the energy so many electric motors were sucking down. Not that he could open up the throttle anyway - 10m/s was about as fast as he dared go with the way the Centipede handled. Even the slightest bump tended to leave it floating above the surface. At 15m/s, he stood a good chance of hitting a rock or micro-crater and flipping it upside-down. So the Centipede crawled across the surface like the insect it was named after, and Calger did his best to let Mun's slight hills and valleys do most of the accelerating.

This is going to take an eternity, he grumped. It didn't help that Mun's featureless gray terrain was mind-numbingly dull. Well, not entirely featureless. It did have craters after all. Little ones, shallow ones, steep ones, and vast - OH KER THERE'S ONE RIGHT IN FRONT OF US! He slammed on the brakes, skidding to a stop bare meters from the cliff-edge of a broad bowl, several kilometers wide.

For a long moment, Calger just stared off the edge of the precipice, weighing his options.

Finally, Bart piped up from the back, "Why did we stop? Do you want me to drive?"

Calger called a group meeting. One by one, they piled out of the Centipede to take stock of the situation.

"So here are our choices," Calger announced. "We can cut across the crater and save an hour or two of travel, but it'll run our batteries down more trying to climb the incline on the far side. Or we can go around and conserve the batteries, but it'll take even longer to get to Arc Luna."

"You think you can actually get us down that cliff in one piece?" Alvin demanded skeptically. "That's a sheer drop at least twenty meters, plus whatever speed we pick up on the way down."

"Can I just jet across?" Seanden asked. "I'm sick of riding in this can. And I have to pee."

"Should've thought of that before we left Kerbin," Bart told him.

"I did! That was ten hours ago!"

Calger banged his foot on the top of the Centipede's hatch to get their attention, but then remembered that sound wouldn't carry in the airless environment. "Focus, crew. Across or around, raise your glove. Who votes across?"

The final tally was three in favor of crossing, three in favor of skirting the crater's edge. The deciding vote was his. He looked past his assembled crew, at the crater's lip once more. He was sick of toeing the throttle and creeping over each hill and depression. Command had built the Centipede to tackle anything - if it couldn't handle a simple crater, there was no point in landing it here in the first place. "Across it is then. Everyone back on board!"

Alvin glared at Calger. "You're going to make us explode. I don't want to explode, Cal."

"Everyone explodes sooner or later, Alvin," Bartbles stated matter-of-factly. "Cal's as good a reason as any."

"I don't think that's how the saying goes, Bart."

Bart raised an eyebrow. "Are you sure? That's how Jeb always tells it."

"Guys, just get in," Calger scolded.

Once settled back in the driver's seat, Calger sized up the crater's edge once more. Despite the power drain, he decided to switch on the SAS, just in case the Centipede bounced too much, or too awkwardly. The wheels spun in the dust as they struggled for traction, and slowly the big rover crept out over the precipice. The nose pitched down, and in Cal's mind he could see the starting lights of Ker-Kart cycling - red, yellow, green! The ground dropped out from under them, and the Centipede plunged down the crater's slope.

Now this was driving! The Centipede accelerated, 10, 20, 30 meters a second, shooting down into the bowl like a wheeled avalanche. Calger fought to keep the wheels facing the ground - on it was hopeless, as even the tiniest hump send the craft skimming, sometimes several meters above the ground. Suddenly he gulped, realizing that the impact tolerance for everything but the wheels was well below 10m/s - if anything but the tires themselves so much as touched the ground, this was all likely to end in spectacular, explosive failure. The tires bounced again, on the left side only, and the whole rover began a lazy barrel roll as it shot across the crater floor. This did not go unnoticed by the crew.

"Are we upside down? I don't want to be upside down. We tend to explode more that way."

"I knew I should've jet-packed for this."

"Cal! For Ker's sake, pull in the solar panels! If you clip them we're screwed!" Bart warned him frantically. Too late now - they would not be safely retracted before the Centipede was upside down. With determined effort, Calger hauled on the control stick and forced the rover to finish its roll, all twenty-four wheels touching down at once. The incline of the crater's opposite edge loomed up at him. Dimly, he wondered what would happen if it launched them back up above the surface. The Centipede had no RCS to slow it, and they'd dumped the empty lander cells long ago.

He needn't have worried. Little by little the speed dropped off and he was able to bring the Centipede back under control. Under its own power, it crested the ridge and began sliding gently down the crater's ejecta. Swiftly, Calger threw on the brakes and extended the ladders. Somewhere in their crazy suicide plunge, a warning light had come on.

Fortunately, it turned out to be nothing more than a blown tire. Structural damage would have been much worse - tires, at least, were replaceable.

Breathing a sigh of relief, Calger took stock of the situation. They were still hundreds of kilometers from Arc Luna, and there would be a lot more craters in the way.

Hopefully the rest of them had Kart lights at their rims as well.

Edited November 5, 2017 by Kieve

[KeithStone]

Great little vessel you have there! Keep up the good work and welcome to the forums!

[Naten]

Yes, waiting for the next update on the story!

[Kieve]

Yes, waiting for the next update on the story!

Honestly, I'm debating the next step myself. Do I make this a hundred-kilometer trek overland, weaving between (and through) craters, or do I say hang it all, send a rescue shuttle, and ship them to Arc Luna in a more conventional style? And not forgetting, in the eight to ten hours it'd take for a rocket to get there, the Centipede may well have reached the base under its own power, so in game time it may simply be more efficient to keep going as-is.

I suppose it's down to my tolerance for frustration at the moment, since as well as the Centipede performed in Kerbin gravity, it's exactly as described above on the Mun - a rhino on rollerskates.

[Kieve]

Damn this mission is starting to wear on me... but we must press on in the name of Science!

The Centipede Mission: Eclipse

Calger was really beginning to hate the Mun. After the last crater, it seemed the cratered rock had only one direction - uphill - and it was taking a severe toll on the Centipede's generous battery supply. He took it as easy on the throttle as he dared, treading a fine line between battery use and keeping up momentum on the never-ending slope. While he drove, Calger listened to the comm chatter. Apparently, Command had sent up a manned deep-space mission to follow their Eeloo Seer launch. Someone kept repeating the code "434-238," which he assumed were either coordinates to something on Eeloo, or somebody's locker combo.

Calger grumped at the controls, wishing he could go faster.

Despite his best efforts however, the constant upward climb took their toll on the Centipede's reserves. With an electric sigh, the throttle went dead and the rover drifted to a halt. Quickly, he engaged the brakes to keep it from rolling backwards. Then he did a double-take at his instruments. Something was wrong - the panels were deployed, but nothing was recharging! Fretting, he popped open the hatch, expecting to see them all broken, but the panels were intact. The fault lay not with the equipment, but with their orbit.

Kerbin was causing a solar eclipse.

There was nothing to be done now but wait. Eventually their planet would move and the sun would recharge the exhausted batteries, but until then they were stuck. Shrugging, Calger shuffled down the Centipede's spine and climbed into the crew compartment. The others looked up in surprise as he entered.

"What did you break now, Cal?" Bart asked. There was no malice or scorn in his voice - it was an honest question expecting a practical answer. Calger just chuckled.

"The sun. Kerbin's eclipsing us and the batteries are dead, so we're stuck here until we can get a charge back." He broke out a pack of cards. "Anyone for a game of Go Fish?"

Kerbin's shadow lingered over them for what felt like an eternity, and the batteries took even longer to charge once it had passed. Seven Kerbals waited, crammed into a capsule made for four, playing cards and eating what few snacks were left. It was dull, but for Calger, a welcome change from the constant slate-gray of Mun's surface. When he got back to Kerbin, he was moving to a tropical forest, with colors.

Finally, the Centipede had enough of a charge to get moving again. To Calger's immense relief, they were near the crest of whatever hill or mountain they'd been ascending.

It was all downhill from here. He flipped on the SAS, sipped his energy drink, and let the rover coast, paying careful attention to keep it oriented wheels-flat as it skimmed over small bumps and slewed sideways around rocks. After conserving power and speed for so long, cruising downhill at 20m/s was as good as flying to Calger. The original landing site was over a hundred kilometers behind them now, and according to their orbital map, they were nearly halfway to Arc Luna!

But they were heading into twilight now, the sun dipping slowly towards the horizon. Could they make it to the Mun-base before sunset left them stranded again..?

Edited November 5, 2017 by Kieve

[Kieve]

The Centipede Mission: End of the Line

In a word: No.

In multiple words: still no.

Calger had pressed on as far as he was able, conserving the batteries where he could and easing the over sized rover up one crater slope after another, but as the sun sank below the horizon he found another problem even harder to fight than the Centipede's poor handling - darkness. Despite the floodlights mounted to the Centipede's cabin, the terrain ahead remained a stubborn inky black. It was impossible for Calger to see where they were going, and with the craters and rolling hills ahead, driving blind through them would almost certainly prove fatal. As he crested another rise, a blip appeared on the HUD - they were within fifty clicks of the base now, automatically registering it with the Centipede's tracking systems. Deciding they'd come far enough for the day's travel, he locked the brakes and pulled in the solar panels. They would wait out the night here.

To pass the time, they listened to radio chatter from Command back on Kerbin. An expedition to Duna was in the works, with Shelsey in command of the Orbiter station and Burhat assigned to the Lander - Ribdrin and Sigby would operate the Science Lab while in the field.

"I can't believe they're putting Ribdrin in the lab," Alvin grumped. "He doesn't know a test tube from a tube sock."

"Maybe not," Bartbles reminded him tartly, "but at least he didn't try to eat them in training." The other Kerbals laughed, and Alvin turned a deeper shade of green.

"That was on a dare and you know it," the embarrassed Kerbal muttered. The rest of the crew laughed harder. Eventually, lacking anything better to do, the travel-weary Kerbals fell asleep.

Munar dawn broke over the dunes with little fanfare. Calger blinked, twisting his large head to work out a cramp in his neck. Dimly, he became aware of the yellow glare forcing its way past the polarized glass. The sun had finally managed to climb back up above the crater peaks, revealing the rolling gray hills ahead. A slow smile spread across his face - it was all downhill from here. The batteries were almost fully recharged already, and he would only need them sparingly to control their descent from the highlands. Anxious to be on the move again, he disengaged the brakes and began the long rolling descent to Arc Luna.

As they skirted another crater, Bartbles switched on the intercom, signalling Calger to stop. Despite their very limited view from the crew module, he'd noticed something interesting in the hillside.

"Bart, we've still got a good thirty clicks to go before we're there," Cal protested. "Can we save admiring the scenery for our arrival at least?"

Bartbles rolled his eyes, forgetting that Calger could not see it through the intercom. "We came here to do Science, Cal. We should take the time to actually Science something."

"Alright," the driver conceded. "You've got five minutes to get back in the 'Pede, otherwise you're walking the rest of the way."

"Knowing your driving, we might live longer that way," Seanden muttered under his breath. Alvin and Anfen smothered their laughter.

Glad to be stretching his legs once more, Bartbles climbed out of the crew module and hit the release on the left-side ladder. As he took a step towards it however, his foot caught in the handholds for the science lab - Mun's low gravity did nothing to halt his momentum, and he performed an awkward somersault into the dust below.

Unfazed, Bart picked himself up and brushed off the clinging Mun-dust. Without proper instruments, there was only so much data he could collect, but he made certain to take a soil sample for Dermin and Kenbas to analyze in the lab. It would give the two something to do at least. Planting a flag to mark the spot for further examination, he climbed back into the crew module and informed Calger they could be on their way once more. Their impatient driver was only too happy to oblige.

An air of excitement permeated the crew - after their hair-raising and wildly off-course landing, they were finally going to see the Outpost. Calger in particular was so distracted by their impending arrival, he neglected to check the terrain mapping, continuing blissfully down the valley until he noticed the ridge rising in front of him. Seven clicks from Bartbles' site, the Centipede drew to a halt once more. One last network of craters lay between them and their destination - a cluster they had already entered without being aware of it.

Fed up with skirting craters, Calger checked the battery reserves. 100% charge - we haven't needed them since entering the valley. A sequence of lights appeared in his head, accompanied by the soft "ding" as they cycled color. They were nearly to Arc Luna, these pits were shallow, and they'd only waste time and energy turning around to circumvent them. If he could've revved the electric motors, he would have.

The Kart lights in his head went green.

Dust and debris smacked the underside of the Centipede as the wheels spun to gain traction. Even in the low gravity, he felt the change in momentum as the big rover accelerated down the crater slope. From the protests coming from the crew module, he wasn't the only one.

"Cal, what the heck are you doing?"

"Oh Ker we're all gonna die! I don't want to die!"

"He's lost his mind! Someone else drive, please!"

Calger just laughed, his mirth tinged with manic glee. The Centipede crested the far side of the middle crater, wheels spinning in empty space as it floated above the terrain.

The best was yet to come, however. It bounced, wheels digging into the grit, and shot down the crater's bowl as though the rhino's skates had become rocket-powered. At 30m/s, Calger knew the slightest wrong move on the controls could spell disaster for the Centipede, but he was past caring. Arc Luna was so close he could taste it. His laughter rose, drowning out the panicked wails from the back with his madness. The crater's wall loomed ahead, but the Centipede barely slowed as its momentum carried it upwards. With a final lurch, the rover was airborne again, in spectacular fashion.

Lacking RCS or rockets, all Calger could do was keep the wheels facing down and hope they didn't hit ground harder than the tires could stand. In the back of his mind, he wondered if he'd taken things too far this time. The Centipede came down.

Metal struts groaned under the strain as the wheels struck the Mun's surface, sixteen tons of Science, Steel, and Kerbals bearing down on top of them, but somehow the craft held together. Skidding wildly across the dunes, Calger slowly brought the careening vehicle back under control. It slid to a stop at the lip of the final crater - the one where, four kilometers away in its bowl, Arc Luna had touched down. For a moment, he paused there on the cliffside, finally able to see their destination.

This was it. With all the caution he had abandoned previously, Calger nosed the Centipede's cabin over the edge. For a heart-stopping moment as the craft pitched forward, he was staring straight down. His foot rested on the brakes. Then they were sliding down the final slope, brakes locked as their intrepid driver did everything he could to fight momentum from building again. Smoother than he believed possible, Calger brought the rover to a brisk cruise over the crater floor.

At long last, they had arrived.

Edited November 5, 2017 by Kieve

[Tw1]

Wow. Magnificent effort.

You will have much experience from that endeavor, and it was very nicely written too.

Have very warm welcome to these forums!