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DDE

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  1. You can do a comparison between F-1 and RD-170, two heavy-lift Kerolox engines from the opposite sides of the Iron Curtain. When it comes to other Soviet motors, if you want a quick overview, you could go through the RD-2xx series (hypergolic, including heavy lift), the RD-301 (a fluorine-ammonia upper stage motor) and RD-701 that goes from Kerolox to H2-lOx mid-flight. And that's just Valentin Glushko's Energomash.
  2. Yes. No. From what I've seen, those mods seem to lack the full capability I'm hinting at (compact stowage before deployment, work as fins). Wrong. Many grid fin systems are equipped with actuators; it seems to be the case for Falcon 9R.
  3. Oh, it's not just for landing. As seen above, they can be used on ascent stages as well.
  4. Guys, could we get these into stock? Make their deployment stageable, so that we can drop them open once we ditch the strap-ons? Right now we're stuck with airbrakes, which don't have the same functionality and produce head-on drag (as intended).
  5. As I thought. From what I read, pointiness is of little help at hypersonic velocities.
  6. Then they are not in a hyperbolic escape trajectory, are they? It's simple, here's some Hollywood science: beyond 100 km, the gravity is so low, you're technically in space, but unless you're a space station, you still have to constantly fire your engines, or you'll fall back to the planet. Good luck rationalizing it. At this point it's easier to just call Them stupid, and try to chain them to a computer and make them play KSP. There is one historic, and one possible future ICBM that are equipped for sending nukes into orbit as part of the illegal Fractional Orbital Bombardment scheme. But escape trajectories would be a step up from that; no ICBM-based booster was used for interplanetary flight either, AFAIK.
  7. Guys, seriously, what do you expect of the mainstream media? You're lucky they didn't try to depict the weapon components as glowing!
  8. I've seen poorly-sourced references to an experimental Soyuz-VI capsule also having a hatch burn-through situation, which didn't destroy the vehicle, but would have killed the crew if there were one.
  9. Wouldn't the falling booster parts significantly limit the available target inclinations? It's one thing when you have the whole Atlantic, or the Pacific, or Kazakhstani steppes; but we're talking about stage separation events over mainland America.
  10. Chapter 9: Shakedown “So, anyone wants to start?” Jeb asked. That ISP management meeting was downright morbid. “Pad’s out of business for two weeks,” Gus began to summarize the report from his own department, “Twenty hectares of soil replaced as part of decon procedures. No salvageable components, sent the trash to Bill anyway. No personnel casualties.” If anything, not having people and the devil of a fuel on the pad simultaneously has worked out pretty well. “Bill?” “At this point all we know is that the lower starboard section of the fuel tank’s aft bulkhead corroded through and then compromised the oxidizer tank, leading to a total vehicle loss. The second explosion was the SRBs detonating. The tank had undergone five inspections, the passivation coating was intact before final assembly, and was subsequently checked for contamination again,” he explained flatly, “At this point I have to ground all Dachshunds until further notice and scrap all of our passivated tank stock.” Bob sighed, and finally asked the question that was eating at last half of those present. “Sabotage?” “I’ll believe it when I’ll find the spanner in the works,” Jeb retorted, causing Val to shake her head, “And, to be honest, scratching the tank with said spanner is something our procedures would’ve picked up. Bill, how much time to mount another Pathfinder onto a Vector stack?” “Also two weeks, we’ll need to boost it from basic design.” “And the effect on Hermes?” “None, we’re progressing as planned, although I think we need to strip it down and recheck everything after this incident?” Jeb had a small smile. “Gene, how many cadets have escaped amidst the panic? “Six.” ---------- The third Pathfinder blasted off as planned; in order to preserve dV of the Terrier stage, Bill slapped a third Sickle booster. “Good roll program, pitching,” Gene narrated the autopilot’s actions. “Flight, Booster, I’ve got minor roll instability.” Bill seemed to tense up. The larger tailfins were supposed to compensate for the wide payload fairing. “Booster, continue reporting.” “Passing max Q, roll stable, continuing pitching.” The rest of ascent, circularization and departure occurred normally, putting the probe on a week-long cruise towards Minmus. And only at this point it became Pathfinder 2. ---------- Two days before the Hermes-A launch, Val stormed into Jeb’s office, and stuck a paper in his face. It was a flight plan. “Bob just tried to run it past me!” she spat. Jeb snatched the document out of her hands. It was surely an interesting one, as it involved the non-existing B2A Hermes First Flight ship, an inclined ecliptic orbit, a magnetosphere scientific payload, and Valentina going on EVA to collect some of said payload; all of this was the ship’s first flight. “I don’t see a problem with it,” he said, shocking her even further. He picked up the phone. “Gus, Jeb here. We’re changing the flight plan for the Hermes. Throw out the monoprop and life support modules, pull off the manoeuvring retrothrusters, move the radiators to the lower mounting position, switch the Communotorn to the ‘32 model, and kit the ring with a plasma tripod, and magneto boom, a particle collector, an EVA tether winch, and fill up the rest with extra main motor tankage. Oh, and throw in a Big Mak for me,” he said, and briefly asked Val, “Want a Big Mak? Yeah, one Big Mak.” He slammed down the phone. “It’s about six hours’ worth of work for him. I didn’t dump money at Universal Storage and had them design a modular SM to be afraid of a last-minute mission change,” he continued. ---------- Despite Val’s continuing grumbling, at launch day she was on the crew gantry, ready for a very interesting day. Jeb clambered through the hatch first, followed by Bill in his blue-marked suit. Val got in last, having the dubious honour of sitting in the pilot seat at the hatch, on the lower deck, so to speak. The Hermes-A stood at the launch pad, her Launch Escape System tower making it as tall as Sarnus V herself, her lines unspoilt by any strap-on boosters. The forced Mainsail stage was quite sufficient for the loft, and the cryogenic upper stage, with its orange tank insulation, would take over from there. The blast-off and initial ascent occurred normally, with the usual thunder and creaking. The altered roll program worked as advertised. As the tanks were being emptied, the acceleration mounted, but it wasn’t as bad as the Vector. There was, however, increasing shimmering. “Sounds like the first stage needs some further detuning,” Bill observed coolly. As planned, the Mainsail cut out abruptly in the upper atmosphere, the ullage motors fired, followed by the Tunguska H2-lOx rocket responsible for achieving most of the downrange velocity. There was a flash as the LES motor fired at the same time as the guillotine, pulling off the boost cover on the return vehicle, exposing the windows; up top, Jeb and Bill had a fairly nice view, while Val has a tiny porthole on the hatch. The fairing jettison, and engine shutdown also proceeded as normal; the crew and Mission Control continued to exchange terse routine reports; Bob was acting CAPCOM. Finally, the alterations to the flight plan kicked in. Val overrode the circularization burn setting; Bill accessed the payload control interface. There was some noise as one of the compartments behind the heat shield opened, and the girder mounting the magnetometers began to telescope outwards. “Magnetometer deployed. Deploying RPWS.” “Confirmed,” Jeb responded, watching one of the three rods of the Radio Plasma Wave Science array extend outside his window. “Deploying particle collectors, commencing exposure on Pad 1.” The ship continued on its half-orbit towards the burn, the solar particles collectors exposed to their origin. The circularization burn began well in the shadow. Tunguska burnt until it ran out of fumes, and then it was jettisoned. With whirring, the pumps of the ship’s own Terrier motor started up, and continued the boost, burning almost half of the fuel in its primary tank as well as the four supplemental drums in place of the life support package. It continued the boost until the apoapsis was almost at Mun orbit. There was almost nothing for the crew to do after that, as the ship’s memory banks were collecting real-time data, and all they did was replace the collector plates as the ship passed through the Von Kerman radiation belts. It wasn’t exactly a chatty voyage. Bill was busy tracking the ship’s mechanisms, Jeb was simply quiet, and Val was too afraid to start the chit-chat, considering the upper deck likely still had the cattle prod. The first day of the mission passed. They were already coming back to the periapsis. It was time to fetch the collectors from the other side of the ship. Bill oversaw the vacuum pumps collect most of the air, and then overrode the pressure equalization valve to vent what was left, as the pod’s door was forced into its sill by internal pressure. Finally, al swung it open, peering at the blackness outside. Carefully she unstrapped herself from the seat, and slipped on the thruster pack. “Local comms check, one-two-three-one-two-three,” she called out. “Good copy,” Jeb responded. “Opening up the tether bay,” Bill mouthed indifferently. Val carefully stepped outside head-first; the outer surface had steps built into it, which she used as handrails. She turned on the helmet lights. The cylinder of the SM was broken by the opened doors of the nearest modular wedge, revealing a winch with a carabineer, which she clamped onto her belt, and then kicked free of the craft. She was drifting aft-wards and away from the craft, protected by the 50 m tether. But still, she activated the pack; with sharp clicks, the compressed nitrogen thrusters fired, spinning her around; with a few pushes of the left joystick, she began moving towards the bow of the craft. Val gave it a good clearance as she began to descend to the opposite side of the vehicle. In addition to all internal lights, Jeb had kicked in the four hull lights and the spotlight in the docking port. She carefully slid towards the other open panel on the hull, sporting the characteristic collector plates sprouting from inside. She landed next to them, grabbing the handrail on the battery compartment, and proceeded to look for the release mechanisms. One-by-one, she retrieved them, and then repeated her trip in reverse. Val slid the collectors into the storage rack as she floated into the craft. “Door closed,” she informed Bill, pulling the thrust pack off. A minute later, the hiss of the air being released was audible. With the scientific mission complete, the crew began plotting their return sequence. The plan formulated in the end required a drop in the apoapsis to reduce the time between the final deorbiting burn, and the entry velocity. The engine fired as usual. “Jeb, permission to augment with RCS thrust?” Bill suddenly piped up. “Granted.” Val initially just raised an eyebrow as the clicks of the monopropellant fuel lines reached the command pod, but that wasn’t the usual sound. The clicks were also coming from the pod’s internal RCS tanks; it was hardly surprising, as the SM’s tanks had been omitted. “Bill?” she finally shouted. “We won’t need a post-sep correction,” he reassured her. A few hours later they executed the second burn, and Val had to agree that the entry would be pretty neat. The landing in the tundra was something Val didn’t exactly expect, though, leading to a fairly protracted camping trip amidst a snowstorm. She was unsure if Bill was more unperturbed by it than usual. ---------- A few days later, Gene Kerman began the procedures for waking up Pathfinder 2. The first imagery of the bumpy Minmus, as well as tiny Kerbin and Mun, appeared on Mission Control’s main screen. Val greeted them with a loud sneeze. “This doesn’t look well,” Bob noted, looking at the notional map compiled through astronomic observation, “By the time we’ll achieve orbit, it’s going to face us with this plateau. Damn, do I miss the tidal locking of the Mun.” “We’re going ahead setting up the insertion anyway,” Gene responded. Around Minmus, the orbits were extremely slow. It took the entire evening for the probe to move into position. They then gave the probe 5 hours to do a pair of orbits, and for Minmus to turn around to provide them with a nice LZ. Then the Pathfinder fired its motors. The descent was also incredibly slow, an entire half an hour. “FIDO, please confirm LZ,” Gene said with sudden alarm. “Uh… stand by, Flight.” That did not inspire confidence, as instead of landing in the middle of the flat mare, the probe was headed for a mountain slope. “Flight, we’ll only have about a hundred meters of clearance,” Bobak reported, as the probe’s motors fired for one last time. The deceleration went as normal, and eventually the craft landed just 50 m short of the slope. This time, there were actual cries of joy as Kerbalkind reached where it had not gone before for the first time since the Sarnus program. The probe began to send through data and imagery. It was landed in a “bay” surrounded by the light-green slopes that seemed rocky. The temperature was slightly above vacuum levels, but Bob growled as he read the accelerometer-seismograph readout. “Flight, could we de-spin the reaction wheels? The probe is shaking.” “Well, it could be the icy mare suffering thermal expansion-compression cycle…” Slava Kerbalov piped up. Jeb struggled to ignore the planetological scuffle that ensured in the back of the amphitheatre, and ordered Gene to fire the DAN. The Dynamic Albedo of Neutrons detector blasted the surface with a particle stream, and tracked the signature of hydrogen. Jeb was hardly interested in finding whether these flat ice fields were made of ice, and more in testing if this thing actually worked, because Pathfinder 1 had detected only the baked regolith. The read-out looked good, though. That thing might settle the argument around the munar polar ice. ---------- A day after the Minmus landing, Bob barged into Jeb’s office, as he usually did. Jeb merely looked up, unperturbed. “When Bill began cutting metal for Athens yesterday, I noticed that the station’s design had been modified from the previous iteration.” Jeb simply looked back, although he seemed slightly concerned by the question that was going to result from that preamble. “You’ve redesigned the aft interface; it now has a new 2.5 m docking collar. The Hermes is simply too small for such a monster, and we don’t have any other ship in our inventory – or do we?” Bob asked, meeting his old friend’s gaze. “Let’s just say…” Jeb started after some consideration, “Let’s just say that there are certain milestones that Fitz would try to prevent us from achieving even if he had not been messing with us to this date, so I would like to compartmentalize the info as much as I can.” “So, that’s how it’s going to be from here on?” Bob grumbled.
  11. I have to say I'm too against this idea. As we've seen, kerbonauts aren't exactly the brightest bunch, and while there is that pesky matter of Pilot levels 4 and 5 being empty, it makes sense that the eggheads and wrench monkeys are kept away from the controls.
  12. What's bizarre about Orion to me is that the LES Boost Protective Cover is rounded and gives it a Soyuz shape!
  13. Yep, and because of how little space is in the wings. Its Soviet cousin has less than half the range, but it's not such a crazy ride on the landing: https://en.wikipedia.org/wiki/Myasishchev_M-55
  14. Guys, they deorbited Mir in the Pacific. Case on controlled scuttling closed. As to uncontrolled, see Skylab. NASA owed the Shire of Esperance A$400 for littering until 2009, and just one kid found 24 fragments around his home; air tanks seemed to have proven particularly durable.
  15. Well, if we go back to the original Conan Doyle novel, Professor Challenger tried to defy that trope and had a camera, back in the day when they were a lot less portable... Naturally, a boating accident on the way back left him with one severely damaged negative, producing a single conspiracy theorist-quality image. His predecessor escaped with a small pterodactyl bone. Of course, the canonical ending is the team dragging a pterodactyl all the way to London. Armageddon is pretty funny. It's clear that they initially listened to NASA advisors - for instance, the overall mission sequence is quite correct, as it compensates for the asteroid's relative velocity, something I wouldn't expect Hollywood to think about - but then they stopped listening and went full science-fantasy.
  16. Yes, but going in for close-in combat you expose yourself to a lot more risk even from an inferior force, assuming you can't snipe individual hostiles with killer crowbars from orbit. So if you value your forces, you would probably be willing to risk ordnance rather than close-in attack platforms.
  17. Except in KSP, this whole thing would have exploded long ago.
  18. Because it's not a subsidy if you get services in return?
  19. [citation needed] There's a paper that suggests entire civilizations can settle inside the event horizon. http://arxiv.org/pdf/1103.6140v4.pdf
  20. And what makes you think that a museum exhibit is to any degree usable. Sure, it's not covered in as much bird crap as this 95% complete second Buran: But it's still an unflyable hunk of metal.
  21. Oh Kraken, where are my backups, how many backups do we have, Gus!?
  22. Yeah, but I think the Shuttle would have a slightly lower aerodynamic load than a simple capsule, wouldn't it?
  23. I guess both Halo: Reach and CoD: Infinite Warfare both fall into the "orbit is when you go high enough and gravity stops" trap too.
  24. Nope. Because of a treason case involving some Chinese, this particular scheme, which also deviates from the textbook design, was actually declassified and widely corroborated.
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