"Ugh. Go make your batteries."
Starlight, still feeling pleased with herself and her genius, went back to do just that.
Author's Notes:
Starlight's the only member of the crew who actually has a lot of work to do— because she's the only one who can do most of it.
I don't intend to do much more in the way of pony lit-crit or RPG shenanigans, but I thought I'd drop a mention that such is still going on. The campaign is in Ankh-Morpork. Cherry plays an assassin noblewoman; Starlight plays a troll; Fireball plays a dwarf; Dragonfly is a member of the thieves' guild; and Spitfire, after laughing herself sick when Mark explained it to her, chose to play a member of the Guild of Seamstresses (hem hem!).
Mark's rule: no wizards, no witches, no City Watch, and no cousins of C. M. O. T. Dibbler. He's started them off in the middle of the adventures of The Light Fantastic, with red star cultists and high intrigue among wizards making it difficult to keep from getting it in the neck in the city. So far the crew have been winning small victories, but more to the point, they're having fun discovering the city in detail. Meantime, they're alternating between Granny Weatherwax and Sam Vimes on the book side of things, having as of Sol 363 got about ninety pages into Witches Abroad, with Feet of Clay to follow.
And hopefully I won't need to go back to those for filler chapters...
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Sol 366
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AMICITAS FLIGHT THREE — MISSION DAY 372
ARES III SOL 366
"This is dumb."
"I'm not arguing the point," Mark replied, working the ratchet wrench while Fireball held the engine bell (one of those salvaged from the MAV descent stage) upside down on top of its normal mounting point on the Amicitas engine. "But if we don't want this thing to flip over in midair, we have to do it."
Fireball couldn't argue with that. They'd considered just sending the rocket motor up as is, all one point four tons of it. After all, Mars had so little air that wind resistance was a non-factor, right? Then Starlight Glimmer had passed on the numbers from the launch tests on Equestria, particularly the launch that sent Chrysalis up to the new giant orbiting spaceship. Mark had done some quick and dirty math and worked out that the test vehicle, being something like eight percent the launch weight of the vehicle used on Chryssy's flight, would leave the pad at something like seventy G's of acceleration...
... or, to put it in terms of meters per second, almost seven hundred meters per second per second if they used the same system. Even with the more restrained system Twilight Sparkle had recommended, the test vehicle would break the Martian speed of sound roughly two-thirds of one second after liftoff.
Fireball knew himself to be a dragon of only moderate intellect, but even he could see two things here. First, every bit of Mars's ability to throw the flight off course by air resistance would come into play practically immediately, and so the engine had to be made at least vaguely aerodynamic if they didn't want it to drop right on top of their heads in several uncomfortably heavy pieces.
Second, even with the aerodynamic shell they were bodging together, only an idiot would be anywhere close to the thing when it launched.
All of that was obvious. But putting the engine bell on a rocket motor backwards, so that the open end just barely fit over the guts of the motor, was just about like that one pony you always got at a party who thought it was the funniest thing in the world to put a lampshade on her head. Again.
Yes, it was a way of saving on scrap metal— not that that was as urgent as it had once been, since they weren't going to be strapping this rocket and its two siblings to the Ares IV MAV anymore, but you didn't need to be a dragon to see the sense of hoarding useful material on a hostile, unpredictable world.
And yes, the material the bell was made of had been specifically designed to withstand tremendous temperatures, air friction, and anything else ponies, dragons, or deranged changelings could throw at it.
All true, and yet it still looked dumb.
"Okay, that's got it," Mark said, giving the last bolt a final tug with his ratchet. "Let's go inside and make the cap and fins."
They'd taken the engine out to Site Epsilon, just east of the cave farm, for launch. It wasn't an absolute guarantee that moving east would prevent the engine from hitting the Hab in case of a mishap, but it helped. Any misfire of the launch system would need quite a bit of help to overcome Mars's rotational velocity.
As for the cave farm and Site Epsilon... well, it could take a direct hit better than the Hab could. Meters of dirt and rock beat a canvas dome for impact resistance any day.
Fireball and Mark wasted no time divesting themselves of their space suits once the airlock finished pressurizing. The interior temperature of the cave now matched that of the Hab, and the valve on the water heating system was being closed off bit by bit as the extra sun crystals throughout the cave did their work. Besides, it was more comfortable out of the suits than in.
"Hey, Starlight!" Fireball shouted. "We taking battery for two minutes of field."
"What for?" Starlight was studying the designs she'd drawn on the whiteboards, making sure she had the adjustments for the launch-test crystal enchantment clear in her mind. She didn't even look up at Fireball's shout.
Fireball almost used the Equestrian word, and then remembered the English, thanks to several episodes from entirely different series that mentioned or showed it being done. "Welding," he said. Thank you, stupid human television.
"Take one of the amethyst batteries," Starlight said. "I drained them day before yesterday. Less than ten percent charge. Two minutes is about all you'll get."
"Good." Most of the batteries were clear quartz, since most of the crystals large enough for the purpose were clear quartz, but a couple of large amethyst chunks had been trimmed and turned into batteries, and they were easy to pick out from the others. Fireball picked it up, ignoring how everything seemed a little heavier than it ought to despite Martian gravity, and carried it over to where Mark had laid out five pieces of pink-painted metal— originally pieces of Amicitas's thin outer hull.
"Okay," Mark said, taking a marker and drawing a not-quite triangle on one of the bits of metal, leaving a square bit on the end that could be bent and bolted to the engine. He then handed the last piece of metal to Fireball. "Are you sure you're up to this? I remember the first rover test."
"It won't hurt anything if not."
"Right. Let me get Starlight to cut these, and I'll be right back."
Fireball watched him go. Yes, Starlight's magic was more efficient, strictly speaking, at cutting. That was fine for the fins. But the nosecone required a little special work.
Fireball stuck the aerials on the battery terminals, switched the battery on, and felt pure magic radiating out from the battery with every sputter and buzz of rainbow sparks. He coughed a couple times to get his inner pilot light re-lit, and then puckered his lips as tightly as he could, breathed in through his nostrils, and spat his tightest, hottest flame directly at the scrap metal in front of him.
It wasn't as hot as the flame from that huge dragon in the Discworld book. No dragon had flame that hot. If they had, more dragons would have challenged Celestia for her throne, and no doubt there'd be a bunch of dragons on the moon or pretty dragon "sculptures" in the Canterlot royal gardens.
For that matter, he couldn't sustain a cutting flame for long even back home, never mind here. He had to move quickly. He cut a quick circle out of the metal— not perfect, but pretty close. He then cut a wedge out of that— like a large slice taken out of a pizza. This took about a minute.
Mmmmm... malachite and anchovy pizza. He'd order five of them the minute he set foot on Equus again. Charge them to Twilight Sparkle or Chrysalis or Ember, whichever was most convenient, just before he handed his resignation to all three.
No. Focus. Cutting is done, but you still need to weld the seam.
The outer skin metal was thin enough for a dragon to bend it easily by hand. Fireball did so, closing up the open wedge so the edges overlapped. Voila— a quick and dirty cone shape. He crimped the seam in a couple of places with his claws to give the seam a bit of a bite, and then he applied the flame again, not quite as hot this time but close. Carefully running the flame up and down the seam, he held the metal edges as tightly together as he could, slagging the overlapping edge so that it melted and bonded to the lower edge.
There. Two minutes and loose change, and he had a metal hat. It was irregular at the mouth of the cone, of course, and a bit wider than the open area on top of the inverted engine bell. That was on purpose. The overlap could be bent over the edge and then fastened onto the engine bell. So long as the weight was close to balanced, and so long as the overall shape was pointy enough to go more or less straight through the thin air of Mars, that was good enough.
If he'd actually been planning to ride inside the thing, he'd have been a lot more careful. Heck, he'd probably hand the whole thing to Starlight or Dragonfly or Mark, go find a corner, and sit on his claws unless asked to lift something. But this was just throwing a dumb object away. Nothing complicated about that.
"Huh. Yeah, that'll work." Mark had returned with four newly cut fins. Starlight now had her own field generator going as she began enchanting the nine small booster blocks and three little target blocks for the test launch.
Fireball switched off his— it had begun to sputter anyway, having run out of stored power.
"How do you get a flame that hot anyway?" the human continued, setting down his load of metal so he could more closely examine the nosecone.
"Think hard. Then make more pressure to breath," Fireball said. "More pressure means hotter flame. Big ball of fire, like show off, like car crash on TV show, not very hot. Little bitty flame, fast air and lots of it, that very hot."
"Huh." Mark gave Fireball a look the dragon couldn't interpret. He just hoped it didn't mean If you die, dibs on dissecting you. "Well, let's weigh all of this. Need to know how much weight we're adding to the payload, after all."
Fireball shook his head. That was humans for you. They'd find a way to take throwing a brick into the sun from two hundred million miles away, add math and science and junk, and make it boring.
He then considered the pony and changeling way of doing things, and then the dragon way, and how various combinations of those had got him here, and he decided he could stand a little boredom.
"I go get scale," he said.
Author's Notes:
No, they're not going to launch anything at 0.7 kilometer per second squared acceleration. There's a good chance the ship engine, even as bricky as it is, would shear apart even in Martian air. More details about how they step down the power next chapter.
Dragon flame in the cartoon is, well, plot-sensitive. Spike can't do anything about timberwolves, but he can spontaneously melt an iceberg wider than a football stadium. So I feel no shame about giving Fireball his moment of ego-reconstruction.
About twelve hours to go on that T-shirt Kickstarter I'm doing. It's just barely over the line, mostly because I did a crap job of publicizing it, but if you were intrigued by any of the designs, you've got until noon Central tomorrow (Monday 7-23-18) to pledge.
https://www.kickstarter.com/projects/1869505034/wlp-shirts-2018-summer-shirt-lineup
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Sol 370
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They gathered in Teddy's office: the usual group of Teddy, Venkat, Mitch, Annie, and (via teleconference) Bruce, plus Mindy Park from SatCom.
"So," Teddy said, once Bruce's call was connected, "how are the Hab crew coming on the booster test?"
"Ready to go on their end," Venkat said. "Mark completed the procedure we sent him to remove the short-range transmitter on the northern weather station and rewire it to boost its signal. Once he connects power, it'll transmit for two hours on the battery it has. The transmitter itself will probably melt in less than half an hour. But for as long as it lasts, the signal strength should be good enough for any orbiter on that side of the planet to pick it up."
"Um, yes," Mindy Park continued. She was the only person in the room not in a neat suit, and her bloodshot eyes made it obvious she didn't care what the higher-ups thought of her old Astrocon T-shirt and sweat pants. "On Sol 374 six of our Mars satellites will be in position to track the launch. I finished testing software updates that will let them track the signal and send that data to us. As soon as Dr. Kapoor gives me authorization, I'll upload the software patches and then go home and go to sleep."
"Our target time is two hours before sunset," Venkat continued. "It's a compromise between the optimal trajectory for a perfect sun intercept and the restrictions of communications. Hermes and Earth both drop below the Hab's horizon about thirty minutes before sunset. As nice as it would be to have one less piece of space junk to deal with, the important part of the test is to verify the numbers the ponies got when this system was tested on their homeworld."
"Yes, about that," Teddy said, picking up a piece of paper. "Did I read this correctly? Six G's of acceleration from the launchpad, rising to a peak of eight and a half G's after three minutes? For a vehicle that weighed twenty tons, fuel and capsule, at launch?"
"So Starlight Glimmer reported, yes," Venkat said. "And to be clear, their best estimate is that their world and Earth have the same diameter and gross mineral composition, so their one G is the same as ours. Also, they didn't get a solid rate of decay for the booster's effectiveness over distance. Their flight was an orbital launch, and the ship went over the horizon while the boosters were still about eighty percent effective. Again, their estimates."
"I understand the caveat," Teddy said. "Now tell me what it means for this launch. One G is nine point eight meters per second squared of acceleration, on Earth, right? So how fast is the test vehicle going to go?"
"Well, there are a lot of differences," Venkat said. "For one thing, after their last test the ponies decided to restrict the power flow to the boosters, both to lengthen the life of the batteries and to prevent the MAV passengers from being crushed. And for this test, instead of using the fifteen large batteries, they're only using nine normal batteries. They predict a net force reduction in the booster system of about sixty percent for the test.
