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Posts posted by Spricigo

  1. 2 hours ago, DareDrop said:

    Could that have something to do with this? In this case it's the Kerbal that gos spinning out of control>


    So I've run into a problem, I've got my engineer on EVA, I've got my construction window open,  and I'm ready to move a part from the storage container over to my Kerbal and as soon as I do that everything blows up. I lose total control over my engineer, he freezes and goes drifting and tumbling off into space. 

    What seems odd is that the space station or the spaceship seems pretty stable in orbit but the engineer almost appears as if he's going in a retro direction keeping pace with rotation of the planet. It's almost like he was planet side and everything else is in space.



    Sometimes during eva construction the kerbal is pushed by the part they are picking  but in my experience those are noticeable but gentle push. What you describe seems way more dramatic. 

    In regard to loss of control, if memory serve me well, you need to exit construction mode to move your kerbal. 




  2. 18 hours ago, king of nowhere said:

    terminal velocity is not a function of the atmosphere. it is, first and foremost, a function of the object moving through it

    well..it's actually a function of both.

     Vt=√(2mg/dACd)m n

    g and d  depends on the atmosphere* while m, A and Cdepends on the craft.

    Which indeed means that such chart wouldn't make sense if only the atmosphere is referenced. There is a table that give the terminal velocity for a imaginary body in diferent elestial bodies there https://wiki.kerbalspaceprogram.com/wiki/Atmosphere 

    18 hours ago, king of nowhere said:

    how can it be extrapolated to different ships

    Using the formula above, I suppose. I guess an spreadsheet would help. Seems a bit impractical for me.

    On 1/31/2024 at 11:26 PM, rogerawong said:

    The Kerbin wiki has a terminal velocity chart

    mm,mmno, there is no chart like that. Look for yourself. https://wiki.kerbalspaceprogram.com/wiki/Kerbin 

    The chart there with density and pressure for altitude may be used to construct the chart you talking about but as pointed above you also need the values for the craft.


    On 1/31/2024 at 11:26 PM, rogerawong said:

    About 9-10 years ago

    At the time KSP was at beta and had a very different and unrealistic drag model.  Anything from that time regarding drag have no use for today KSP.




    *technically g depends on the celestial body and height. However so is d    ...technically

  3. 10 hours ago, king of nowhere said:

    and I suddenly got a lot more acceleration than drifting could be accounted for.

    is an old bug, I have  experienced it myself several times. Still..just not what is happening in the videos above.

    I get that you were not in doubt but for future reference the easiest way to confirm that bug is looking at the orbital period when no thrust is applied.

    However, no idea how to actually reproduce the bug. (maybe it need be two bugs that love each other :confused:)

  4. On 12/8/2023 at 11:28 AM, Kerbart said:

    Your video, quite frankly, is bad.

    I'd argue not quite that bad. We  can  extract a lot of information from what is show there .

    If you pay close attention you will notice that ctbram does indeed cut the thrust when the relative velocity is 0.0m/s. At this point we may observe the relative velocity is not constant.

    Exactly what he want to show us. But what catches our attention is something else:

    A moment later the engine is reactivated when we are not expecting . That is because ctbram is relying on SAS to point the ship retrograde and he can't do it with speed below 1m/s.  "inefficient"?  Maybe, but it is not the "mysterious" acceleration ctbram is referring to. It distract us for a moment but as soon we notice what is happening it becomes irrelevant.


    Let's get back to the situation where Barlin Kerman is chasing the Target and he just cut the thrust. Ctbram's question to us: why, at this moment, the relative velocity is not constant?


    K       position of Kerbin

    B       position of Barlin

    T       position of Target

    ab      acceleration of  Barlin in the direction BK due gravity

    at      acceleration of Target in the direction TK due gravity.

    db    distance between Barlin and Kerbin

    d    distance between Target and Kerbin

    Given the angle BKT, make sense to reescribe aas:

      atcos(BKT)r  + atsen(BKT)

    where is the direction BK and   the perpendicular direction to BK within the orbital plane. (For the sake of simplicity let's assume relative inclination is zero.) 

    considering some numerical values  for at and BKT:

    at BKT atsen(BKT)
    9.8m/s2 171.033mm/s2
    9.8m/s2 0,1º 17.104mm/s2
    9.8m/s2 0,01º 1.710mm/s2
    9.8m/s2 0,001º 0.171mm/s2

    as we can see the acceleration component in the direction approaches  zero as the angle BKT approaches zero. In fact at for BKT = 0 (B, K and T are collinear) we have:

    atcos(0)r  + atsen(0)s       ==    atr  

    But wait. This is acceleration due gravity: 

    g=GM/d2   where GM is constant and d is the distance between the central body (Kerbin) and the orbiting ship. 

    we want to find the situation were ab - at = 0 

    GM/db2 - GM/dt2 = 0 

    1/db2 = 1/dt2

    db =dt

    Conclusion: to have exactly the same acceleration due gravity (amount and direction) Barlin  and Target need to be in exactly the same position relative to Kerbin. The acceleration  you observe is the acceleration of the non-inertial frame of reference due Kerbin's gravity.


    PS: the special  case were both craft are in the same perfectly circular orbit is left as an exercise to the reader

  5. 7 hours ago, Hotel26 said:

    Apologize for the above (especially after ten years long gone) but I suggest it makes 100% difference to the utility of the answer.

    Oh, I guess you got some valid points there.  No need for apologizes.

    In any case, precision is limited both on your maneuvers and the displayed information. E.g. 0.0m/s may be 0.0000041592653589793... (or maybe as much as 0.0499).  So, while there is way to reduce that imprecision (matching orbits instead of only reduce relative speed,  using less powerful engines, doing the rendezvous at higher orbit, etc...), keep in mind that there will still be  some drifting happening just under your nose.

  6. 8 hours ago, ctbram said:

    A body in motion stays in motion unless acted on by an external force!!!!!!

    Yes, without an external force those crafts would be moving with constant velocity in a straight line.  Are they?

    Given the game's limitations  (it is a game after all) the physics is quite accurate, what you experienced is what is supposed to happen. You just got confused because the non-inertial referential, gravity is acting upon the crafts the whole time.


  7. 44 minutes ago, Poppa Wheelie said:

    Use vacuum numbers only, for the whole thing.  Your 3400m/s target for achieving orbit is the vacuum dV total of all stages used from Kerbin surface until orbit is achieved.

    3.4km/s with twr~1.5 is a convenient rule of thumbs. However keep in mind: those are "rookie numbers".  I'd say an experienced player can consistently archive orbit with less than 3.2km/s and do it with  less  than 3km/s if really trying. 

    Ironically, with enough experience we stop to follow our own advice.


  8. 6 minutes ago, Superfluous J said:

    Yes. Vacuum numbers are actually pretty accurate even at 10km up.

    I was about to say almost the same, just 20km instead of 10km


    On 11/24/2023 at 9:34 AM, Bej Kerman said:

    I think either Matt Lowne or Stratzenblitz came up with this technique for getting consistent turns, but a good way to repeat the same gravity turn profile consistently is to turn to five degrees on your navball right after launch then set SAS to prograde at a certain altitude (or speed, I cant remember but the latter may be better for low TWR launchers).

    You mean Spricigo's Technique*? ;)Just that turning after launch still require a bit of skill/practice to be consistent,  turn it before leaving the VAB and hold it with launch clamps.  How much you turn  varies with the rocket (More TWR, shallower angle)  If you are precise enough with the design/setup you don't even need SAS or launch clamps e. g.  Still, is a tradeoff, you get consistent turns at the cost of more time spent at the design phase.


    *Certainly others came up with the same idea independently. Still, I'm using it for almost every single rocket except   launch since 2016 and sharing crafts designed to do it  since 2017,  I guess my case is pretty good.


  9. On 11/27/2023 at 9:19 PM, Jeb x Valentina said:

    The plan is to have a scientist sitting on top of a tank (which tank is also up to you, as long as it's stock, low mass and has a decent amount of Lf/Ox) with a couple cells and batteries attached, powering a single ion engine.


    4 hours ago, Jeb x Valentina said:

    Bad news. Turns out it's impossible to get the ratio right while still having over 10 km/s... 

    It is very possible. In fact you have so little payload (1 kerbal) that it could be done with chemical rockets. Example given:



    (no fuel cell there because i don't need to power a ion engine. 2 batteries and 2 solar panel are more than i need already)

    With the dawn you can get even more deltaV or just have the required 10km/s in a much lighter craft. maybe you just need to drop some dead weight or better use the staging. Pst a screenshort of your craft and we can see what can be improved.

  10. On 11/20/2023 at 5:24 PM, Andrew1233 said:

    i want it to float and have a speed about 40-50 meters/s

    Well, that is not difficult in KSP. However if you designed something that can go that fast in water is not unlikely it can fly also (maybe it only can hurl itself a couple meters in the air and crash immediately after, which is bad enough). At this point your option became; 1.design it to fly well and land safely 2.design it to not fly (You may also just suffer, but I will ignore that "option").

    Here an example of the later:



    Sorry for the bad quality, for some reason KSP not taking SS for me.



    For a craft of that size the 2 Juno engines are just enough to give TWR about 1, if anything It need just a tiny bit of lift to fly.  Indeed, flying straight is not a problem to this "bird", despite being a few degrees away from an uncontrolled spin. But that really don't matter because I made very hard to take off with it:

    -The Center of lift is far behind the Center of Mass;

    -There is a pair of Delta-Deluxe winglets at the rear below the centerline;

    -The Line of Thrust is a hair above the Center of Mass;

    -4 elevons below the surface further stabilize the craft;

    -Reaction wheels are disabled and pitch authority is limited to pair of  elevons to avoid SAS overcorrection

    -Center of Mass well between the Wheels/Keels.

    All of that combined makes for a very stable craft, It can maintain 30m/s with 4x physical warp. (You'll notice it oscillates but it stay in the water) It turn very easily, just roll in the desired direction and it will pivot around that keel. On land it can technically go much faster but flat terrain is required to do safely. All in all, quite a fun craft to play with but unfortunately boats are limited in scope and usefulness.


    Mind you, for a seaplane you need something very different, the craft must be able to raise from the waves. The CoL will be much closer CoM, same with keels(better yet to not even have it), wings with incidence and enough control surfaces for a decisive pitch up when you get up to takeoff speed. 




  11. Since you mention possible drag issue I get that you want to land it somewhere with a atmosphere.(not Duna)  We can also see that the landing apparatus is disposable, so you are not planing to take of later.

    It seems to me the obvious solution is to strap some parachutes in the top of the rover, keep some much smaller engines to  steer it to the correct landing spot and decelerate the craft enough so you can open the parachutes. What I'm missing there? 

  12. On 11/10/2023 at 12:28 PM, king of nowhere said:

    I am afraid ferrying tourists around the moons of kerbin is the only way to go. once you take interplanetary missions, it's going to take years in any case.

    First, sorry for the late replay (I'm not the regular I used to be  anymore)

    Tourism is the most straight-forward and gives reliable reputation even if you don't go further than  Kerbin orbit.(reason why I came up with this gambiarra * (and some others)  ). However the entire point of this craft is to farm tourist mission before you go to Mun/Minmus  since tourist don't ask to go where you never went (and that is also the reason , for me,  this craft became obsolete). That did  work because I knew I would accept a bunch of contracts,  fill the craft, hop into orbit, return , recover and repeat. If you already landed in several other celestial bodies then you need either to sort the tourists or to carry then the entire trip even if they only ask for a part of it.  

    Now, what I don't see working that well is doing just a couple of tourism contracts each trip because most accepted contracts are to do something else far from Kerbin. As I see, the key to make tourist worthwhile is increase tourist capacity while reducing cost and play time to do the mission. At this point that is not there anymore. If I wanted to prioritize reputation growth,  I'd rather setup Appreciation Campaign or/and Open Source Tech Program and do whatever missions I'm already doing. 


    *image of the craft: 




  13. 12 hours ago, king of nowhere said:

    well, the best way to get money, science and reputation all together is to get a tourist contract to land on mun or minmus ...

    That is definitively one way to go about it. However, as I see it, what makes that strategy worthwhile is not the kind of contract you take (other kinds of contract could work as well) but the fact those are contracts to where you are going to anyway.

    Also, I personally don't like to bring  tourist that far (too much increased complexity for my liking).  Low Kerbin orbit is Ok,  fly by Mun/Minmus I'd consider and Mun/Minmus orbit is already pushing it. On the other hand I really enjoy to do rescue and  launch satellite mission.  I never had the urge to figure out if that  gives me more funds/mission or funds/time because that is what gives me more fun/time.  (and that's the metric that matters to me.) 


  14. 7 hours ago, king of nowhere said:

    when a station explodes because you did some eva construction on it, that's an obvious bug

    Well..there is quite a difference between "the station go boom" and "the station got a mag  boom*" :wink:

    The issue there is that if you attach anything  to a vessel it loses it's "fully assembled at launch" status and therefore  cannot fulfill the requirements to the contract.

    Personally I think that  if the station was assembled  at launch time enough to fulfill the contract and it didn't lose any necessary part to do so at any time then it should be still a valid vessel for it and, since the game its not as good as the player to keep track of  that, is fair to use AltF12ernative methods to convince the game the game to give that check mark. Anyways, If someone prefer to go for what the game says is also fair since is their game to decide.


    As for OP's  troubles, you can always use a  different save to test things and make sure it can work when you try it in your "serious" save.  If you consider unlikely to complete the contract and make a profit then let it expire (or go ahead and cancel it if you need that contract slot open immediately), otherwise you are just prolonging the problem.

    Also, don't rely on bailout grants. Strategies as a whole are not that useful to begin with  but this one is quite bad.  Instead keep some open space for cash grabbing contracts (don't be afraid to decline other contracts because the penalty, its quite low and you can set it to 0 in the difficult settings, although be careful with declining too many contracts that you may want to do later since over time it will make the game less likely to offer similar contracts). Alternatively setup a  science farm (a bunch of labs) on Minmus and trade  science for funds instead (patent licensing gives much better rates than research  rights sell-out)  If you still feel like to trade some reputation  for money setup a fundraising campaign instead of bailout grants for better rates.

    *This thing:

  15. On 2/27/2022 at 11:59 AM, king of nowhere said:

    caveman restriction


    On 2/27/2022 at 2:34 PM, king of nowhere said:

     I could tamper with the file to do something more radical but easier

    Your commitment is both amazing and amusing. Even the hack to solve the bug was under caveman restrictions.  

    If you want to do it in a less challenging way next time, consider using


  16. On 3/4/2022 at 9:52 AM, TanDeeJay said:
    On 1/27/2014 at 8:44 AM, ShadowDragon8685 said:

    Is there any practical point to installing fairings without FAR? I haven't got it installed and don't intend to. Fairings look boss as all heck and watching them pop in orbit is great, but without FAR, are they just adding mass and (paradoxically,) drag? Or do they actually shield the drag of their payload and replace it all with their own drag in stock, because that would probably justify the weight several times over on the ascent stage.

    Definitely!  I have launched some loads that were unlaunchable until I installed fairings.

    I'm sorry to sy that you are wrong since the question was made in 2014, at the time, without FAR, fairings would, like @ShadowDragon8685 supposed, just add mass and drag.

    I guess you noticed the aero model got some adjustments since then.

  17. Oi Jr,

    Espero que você aparece pra ver a resposta (ou ao menos consiga solucionar de outra maneira). Primeiramente peço desculpas porque uso inglês no meu jogo e realmente não sei como estão os termos em português, por isso estou passando os nomes em inglês mesmo e colocar a minha tradução entre parênteses deve ser algo do tipo mas não exatamente igual.

    Existe entre as opções do jogo "allow advanced tweakables" (permitir ajustes avançados). Você precisa marcar opção para aparecer nas Part Action Window (Janelas de Ação das Partes) comandos adicionais que ficam escondidos por padrão pra não sobrecarregar o jogador novato de informação (infelizmente tem coisa bem útil que fica escondida com isso) com essa opção ativada vão aparecer as opções de  "flow priority" (prioridade de fluxo)  que vou mencionar,  a maioria em tanques de combustíveis mas algumas em outras partes para permitir ou impedir o fluxo de combustível.

    Quando você configura a sequência de estágio, o jogo vai automaticamente ajustando as prioridades dos  tanques de combustível fazendo com que  seja consumido o combustível dos tanques mais afastado da root part (parte raiz). Acontece que em alguns casos o jogo pode se confundir e zoar um pouco essa ordem, ou o jogador pode preferir uma ordem diferente da padrão por uma serie de motivos. Com o "flow priority" visível você pode conferir se a ordem é a que você quer e ajustar nos botões + e - se não for este o caso.

    Os motores vão consumir combustível dos tanques acessíveis que tiverem prioridade mais alta. O tanque vai estar inacessível se no caminho houver  parte que não permita crossfeed(passagem de combustível) o que normalmente vai estar informado na parte, mas inclui  algumas partes estruturais e heatshields(escudos térmicos), no caso dos fuel duct(dutos de combustível) eles permitem passagem somente em um sentido,  decouplers(desacopladores) tem uma opção para permitir e por padrão está desabilitado enquanto docking ports(portas de atracação) são habilitadas por padrão e tem opção de desabilitar.

  18. On 4/30/2021 at 2:11 AM, dokii7071 said:

    is this normal or can I fix this?

    There is several things to improve in your craft:

    •  The thrust axis should be aligned with Center of Mass. 
    • Rearrange the fuel tanks so the Center of Mass  don't shift (too much) with fuel consumption.
    • Move the control surfaces further away from the center of mass so they get enough leverage; 
    • Give some incidence for our wings for better lift/drag characteristics of the craft

    Designing a plane can be very tricky for a new player, it's quite easy to get overwhelmed with all the details that you need to pay attention to.  To understand those fine details is probably a good idea to look into the tutorial there is  around, there are a couple:



    warning: while there is still plenty of good info in those old  tutorials, they are made for older versions of KSP and some details may just not be true anymore due to changes in the game.

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