NicolaSix

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About NicolaSix

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  1. I'd probably end up MM'ing those into thinner parts if I did, docking parts are THICC Yeah, actually rereading through the documents I have, while there's mention of a "spin table assembly", it /seems/ like there was a set of two to four retros mounted into the Upper D assembly that would initiate a roll in the upper stages just prior to the separation event. I tracked down enough additional information[1] about them to get their thrust/burn-time/weight/dimensions etc, so I guess I'll MM myself some 25-50% scale Zoot kick motors from the Mercury and pretend they're the 1KS40, 0.6KS40 or 1KS75 kick motors. While researching I came across the Athena RTV, another american all-solid rocket, though a sounding one, comprised of 4 x Recruit + 1 x Castor 4 + 1 x Antares 2 + 1 x 23-KS-11000/Alcor IA, it's probably something you could MM patch into existence, plus the bottom stage looks kinda cool, it's a castor with the 4 recruits as integral boosters. As far as I've read, every scout launch would initiate a spin of the upper stage (Altair+Payload) prior to separation; the Wallops launch facility had a dedicated spin test building and all the testing for upper stage motors was fired during spin, I imagine while all payloads would be spun to have attitude control during orbital insertion, some may have included de-spin mechanisms to cancel out the roll. The Yo-Yo Despin mechanism/technique was invented in '62 so possibly used on some payloads for the Scout among other LVs. In KSP I'd just use the almost-always ridiculously overpowered probe roll control. Which reminds me I want to take the torque wheel off the explorer I, when attached to an Altair it's got enough torque to start an attitude change, but not enough to stop in time, so the (not-great, tbf) KSP attitude system just starts yawing back and forth with the maximum angle range slowly increasing until you fire the rocket at 30° offset.. -.- [1]: - CR-259 - Evaluation of the 1KS75/MARC-36A1 spin motor - Fig 51 - Pg 152 - CR-165-950 - Extract from 'Micropropulsion For Small Spacecraft'
  2. I eventually found the answer in TM-749-48 (pg 9) which is that there was a coast period (to 130,000ft altitude) between first stage ignition and second stage ignition where the first stage remained attached, I was too used to the liquid engine/Kerbal concept of constant thrust during ascent, so I'm rewriting my kOS launch/ascent program to follow the launch protocol defined in the handbook. So technically it was reason 3, sudden dead-mass loss, but also partially that stage 2,3,4 were never even vaguely designed with an aerodynamic profile. Now if I can just work out the best way to make kOS initiate a high RPM roll then disengage control.. -- feel like carefully placed retros would be helpful here, given we don't have a part that is a 40lb spin table.
  3. I did actually sit down properly for a day and flexed my research skills, so I now have way more information, including the flight operations manual and the elusive CR-165-950. I adjusted all my configurations to be in line with those, since they're gross weights for the SRM's + aerodynamic casing/piping, rather than just the SRM's and have spent since about Friday last week trying to replicate the avionics/pitch programs used by the scout in kOS, trying to get to a consistent orbital capability from it. Which I managed, but only for sub-100kg payloads (currently a Explorer I sitting on a baby sargeant with a kOS module MM'ed into it, totals 88kg with ballast) which contradicts the claimed 210kg to a 1.0x scale 100km orbit in the wiki, maybe my ascent paths are wrong, once I have it all working I'll publish my work + results somewhere. I started condensing the information into a document: https://docs.google.com/document/d/1niZLGEaxYqfpwqxksiyeOFs-ZxXIYFdhxlVGr80G_hI/edit?usp=sharing Document Index: https://docs.google.com/document/d/1ktPAMmWWIQOKl4x83g8htmVoEwqBkZ1elxi03etU04w/edit?usp=sharing There are some files I've yet to index and catalogue, I'll eventually go through the index and add relevant content notes about what's in the documents. On an actual mod note, I have noticed that the Castor stage tends to have a bit of a wonky aerodynamic profile and will happily flip itself over immediately unless it's basically in upper atmosphere; I ended up having to both reduce the effective thrust to 50% on the Algol for a longer burn time to put the castor stage higher in the atmosphere and also add some 40% scale Algol fins to the bottom of the Castor stage to get it to fly without pitching over wildly, amusingly the Antares is either light enough or has enough RCS control to recover from any amount of over steering from the Castor. That's with the stock configuration patch I made, just changes the RCS to HTP and adds solid fuel with resource tanks (thus avoiding the *4 factor applied to all stock SRM's solid fuel levels by RealFuels*) I'm hoping once I've smoothed out the ascent/orbital-insert programs for stock, I'll apply the more in depth configuration to the parts and test it as Scout variants , since all the documentation seems to claim that the X-n/A/B/C and D/E/F/G were basically the same in construction, only using upgraded SRM's and in some cases changing diameter slightly to accommodate larger stage 2 and 3 SRM's, and any adjustments to pitch program were based on payload and orbital insertion requirements. I'm doing an in-depth career game with kOS, so next on my list for careful inspection is probably the Juno I/Jupiter program * Which is very amusing because when applied to the Algol and Altair in stock scale it means you can easily hit 125km apo with a single burn from the algol, and have more than enough dV in the Castor+Antares to circularise without ever touching the 40 solid fuel in the altair.
  4. Hmm, I'm not sure the scout stages can really lose any more mass, the Antares is only ~70kg dry (which is far lighter than the real Antares (even scaled..), except the Antares-3 -- that ones weird..*) currently, in 3.2x it puts a 90kg payload into a 200km orbit after a little tweaking so it 'feels' like it's about right, RSS you'd need about 4x the delta-V per stage, which is basically 'moar fuel' as far as I can guess via my spreadsheet I kinda just wanted to avoid having the Scout being capable of TLI of probes, since that's kinda what the Agena/Centaur is there for; the upside is switching to the X-1's engine configurations makes a pretty good sub-orbital rocket too I also noticed that during ascent, if you have the Castor's RCS system on to provide stability; the sep event of the Algol 1 will cause the COM to change wildly and normally the Castor+Antares immediately flips itself over, I'm not sure if this is just a case of KSP's sometimes wonky RCS PID controllers over-compensating or if the thruster power of the Castor could do with a tweak downwards so it doesn't apply as strong a corrective force. I'm working around it in my kOS scripts by disabling the lower RCS systems ~0.5s before sep then re-enabling it about a second later, the rocket still has a good wobble in it's pitch but at least doesn't pitch over. I'm guessing this is mostly just KSP's own soupy atmosphere and flight characteristics. *The Antares-3 is 98kg dry compared to the ~350kg of the others, I think this is because it's basically HTPB wrapped in kevlar then set on fire, I'm guessing it lacks the attitude control system of the Antares-2 or 4, but couldn't find any pictures or technical drawings to confirm that, I considered excluding it entirely from the engine configurations but it almost balances against the other engines in the end, so I left it in, it just gets a 0.33 massMultiplier when used, making the Antares stage about 22kg dry.
  5. Thanks! I realised the scout is a little oversize and it's honestly not my intent to 'rebalance' it in any meaningful way, it works perfectly in stock + 3.2x in my experience, just the thing with the fuel tanks threw me, I intend to throw a patch into the RealFuels that only fixes the RCS tanks and doesn't touch the engine configurations/mass otherwise. I tried to balance engine thrust values and mass around the original parts definitions, just with the ability to tweak the specifics; the patch provided atm is more for the "I want to play RO+RP-0 but don't want to learn a degree in rocket engineering first" tbh. It also just bugged me that the description said "Cold gas control system" and then real fuels goes and throws in a hydrazine RCS system, afaik the CG-RCS is only ther on the Antares to spin up the Altair prior to orbital insertion anyway, so I figure it only needs a dozen or so m/s of RCS at most. That sounds about right, I couldn't really find specific information about the scout variants physical sizing apart from the occasional diameter or length of an individual SRM; weird given how the Scout was active for a good 30 years Also if anyone has a better idea on how to balance for different scalings other than "Put more fuel in it" I'm all ears, I'd considered just leaving the tank's volume at a reasonable amount of propellant for a 6.4x, then setting the default tank usage to a scaled value for the system size so it's roughly "gets to orbit" out of the box, then let the player tweak it; I'm guessing beyond 3.2x though one would be required to bump up the actual thrust output of the stages.
  6. Hi all, Very long time lurker, but anyway; hopefully a useful contribution! Playing through a 3.2x rescale with RealFuels I immediately noticed that the weights on the Scout's SRM pieces are... off slightly, normally <1KG or so, which obviously messes with the delta-V and TWR values quite a bit. Tracked this down to RealFuels replacing any Monopropellant tanks with Hydrazine unless told otherwise and also reducing the weight of the engine a bit because of realisticMass being set to true by default, so spent the last two days researching the absolute heck outta the early Scout SRM's and come up with this as a result https://docs.google.com/spreadsheets/d/1JEJAY-MwEXvam10oA3hPiSNA0qHiTyJPiBOCGOm4EiI/edit#gid=0 What started as just fixing the hydrazine conversion sorta became a "what if I use ModuleEnginesRF as well" so: https://gist.github.com/LambdaSix/f43aac45632f0069555209db4df14d15 I haven't tested it in anything but 3.2x yet, but with tweaking on the fuel levels in the tanks and careful flying, those configs roughly get a four stage Scout X-3 LV into about a 200x200 orbit with a 125KG payload with a little bit of delta-V left over. While testing I noticed. Basically as per the spreadsheet this (sorta) turns the 4 SRM's for the Scout into nearly all variants (where there was a meaningful difference) required to make up most variants of the Scout launch vehicle, I only really tested the X-3 configuration which is below, not every variant is is included since I just couldn't find any useful information for some of them. Type Stage 1 Stage 2 Stage 3 Stage 4 X-3 UTC Algol 2A Thiokol Castor 1 Hercules Antares 2A UTC Altair 1A As probably expected when running with RealFuels + Rescale, there's a good amount of tweaking needed on the specific fuel levels to ensure TWR's and dV match what's expected, so this isn't really a lego kit. Predominantly the real fix is "if realfuels is installed, put some appropriate RCS tanks into the engine or :FINAL override it" -- so this affects parts like the Athena's 'Paxus-MGL/S4-PSBS "Orestes" Post Boost Vehicle' (bluedog_Peacekeeper_PostBoostVehicle) since it replaces the monoprop tank with a hydrazine tank then replaces the RCS thruster resources with Hydrazine, which kinda breaks the main OAMS engine a little. So my TODO list does include other parts where they include some kind of RCS system that RealFuels is breaking. Also on my TODO list is probably putting all my collected flight & assembly notes into the wiki page for the Scout, since it currently lacks info about what stages it's even using.