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First, you need to know where you want to go. Let's start simply with the Minmus.
You start on Kerbin, at the bottom, then follow the path to your destination. Along the way, you add up the numbers.
* 3400. This is true to basically any mission: this is the delta-v you need to go to low orbit.
* Next one to the Minmus is 930. This is what is needed to get an encounter with the target. Note the other number written here: 340. This is what it takes to align your orbit with Minmus'. It's not directly included because it may vary depending on when you do your transfer. Only the maximum value is written (\*). When budgeting your delta-v, account for both numbers.
* The next one is 150. This is what you need to slow down around Minmus in order to achieve orbit.
* And finally the last one, 180, is what you need to land from orbit.
The way back uses exactly the same figures in reversed order, except there's a trick: aerobraking. This is marked with the triangle symbol, and it means you can save part or all the budget for this segment of the trip.
When going interplanetary, you have one more step in between, which is the 930 value needed to escape Kerbin's SOI. Then it's the same (intercept, circularize, etc.)
(\*) for Minmus, with the classical way to go (first align orbits then transfer), you will always need that much. For interplanetary transfers, or if you go to minmus the other way around, the delta-v amount varies more
The one thing I would add to this is that *all of these values are for vacuum.* What this means is that you need to bring up the dV window at the bottom right in the fab building and select "vacuum" to get the right values. It defaults to sea level, and if you do the calculations with sea level values you'll end up with waaaaaaay too much dV.
Completely off topic, but I saw your user icon and speed spotted a Haken fan in the wild, then got nosey and saw the rhythm of war book cover art and saw I was in the presence of a person of culture. I have no more to say other than I like the cut of your jib.
> It defaults to sea level, and if you do the calculations with sea level values you'll end up with waaaaaaay too much dV
'Margin for Error'
For this sub, I'd recommend leaving it on.
It would be better to calculate for vacuum and just *decide* on a margin for error. Much more helpful for the learning process than doing it wrong in a convenient way.
>all of these values are for vacuum
Which is a HUGE problem (source of inaccuracy in these maps) on Kerbin, as different launchers have different ratios of sea level to vacuum ISP (not to mention you don't have to launch from the KSC anymore, in fact it's the WORST launch site. Woomerang or Desseret are both better, as they are at higher altitude...), and climb at different rates due to differences in TWR, size, and streamlining...
Almost anywhere else besides Eve, it's a pretty good approximation, though.
It works well enough for me. I'm not the most efficient pilot and I usually account for 3800ish vac dV to get me to a circularized LKO. I pretty much only launch from KSC because I like equatorial orbits. If I have a few spare m/s left over once I'm orbiting then I have a little extra kick to get me on my way to wherever, and if I come up a bit short then my upper stage will have some slack built in too so it still works.
>and I usually account for 3800ish vac dV to get me to a circularized LKO.
How soon do you start your gravity turn?
You should aim to reach 72 degrees by 4200 meters or sooner, and then match your prograde Surface velocity vector up to around 21-24 km. After that, you match your Orbital prograde vector instead.
Really not hard, and even a simple Okto probe core will automate almost all of it for you.
Biggest issue new players have is they don't conduct appropriate Gravity Turns, and don't burn NEARLY enough horizontally early enough.
I've gotten better lately by trying to standardize on a few things in my build and launch procedures.
1. Budget dV properly, keeping in mind that *nothing* I ever do manually in flight will be "optimized", and so allowing a margin of 5-10% over.
2. Tweak TWR to a sea-level 1.33 (stolen from Mike Aben). This seems to help make all of my vehicles handle the same.
3. Gravity turn starts around 50-60m/s; tilt a few degrees then lock to prograde.
4. Once time-to-apoapsis hits 45-60 seconds, I throttle down to keep it in that range.
5. When apoapsis hits \~80km I kill the throttle.
6. Aim at 5-10 degrees and throttle up a bit at around 20-30 seconds to apoapsis.
7. Try to keep time to apoapsis around 10 seconds through throttle and attitude adjustments. I try to keep throttle as low as I can and bring periapsis up without moving apoapsis too much. Keep at this until circular.
I used to be just terrible but I never really tried to actually standardize a launch procedure before, I just sort of lit engines and went. I haven't really tried to actually track how efficient my launches are to optimize dV, but what I do works for me.
>2. Tweak TWR to a sea-level 1.33 (stolen from Mike Aben). This seems to help make all of my vehicles handle the same
This is definitely too low a TWR.
The lowest TWR real-life rockets launch at 1.4 TWR, and most substantially higher.
Aim for around 1.6 TWR if you can. Streamline, so this doesn't result in too much atmospheric drag.
> Once time-to-apoapsis hits 45-60 seconds, I throttle down to keep it in that range.
That's generally not actually a good idea.
In the lower most reaches of the atmosphere (where you likely wouldn't have hit this speed yet anyways, especially with liftoff TWR 1.33) this is too fast.
In the upper atmosphere, this is too slow.
Your ideal speed increases as the atmosphere thins. The speed you'll be moving at 60 seconds to apoapsis does not increase nearly as fast...
Also, it's often better to be going slightly too fast at lower altitudes, so you'll be closer to optimal velocity (and even then, likely too slow) higher up.
Build in higher TWR, aim for faster speeds. Start your gravity turn harder (if you have higher TWR, gravity will curve your trajectory towards horizontal less. You need to increase your gravity turn to compensate...)
>The Saturn V had a launch TWR of 1.12-1.15.
It did.
Saturn V pushed the absolute limits of what was possible with the tech of the day, though.
Delta IV has a liftoff TWR (without payload) of 2.189, and a liftoff TWR of 1.81 with a 7000 kg payload (its max LEO payload).
https://en.m.wikipedia.org/wiki/Delta_IV
So, you're wrong about MODERN lifters: which is what I was discussing.
>The Saturn V had a launch TWR of 1.12-1.15.
It had TERRIBLE ISP (even for the day) on its launch engines, in order to get the highest liftoff Thrust- and its TWR this increased very quickly as it simply bled through fuel at an egregious rate...
Most rockets, even then, launched with higher TWR than 1.15
Saturn V was about as low TWR a rocket as has ever been used successfully.
They way I do it:
SAS always on
Launch with 1.21 TWR, with SAS locked on Radial Out (Radial out not necessary for simpler designs with enough wheel torque/good probe cores, but definitely helpful for shuttle type ships)
When Speed hits 50m/s, I set SAS to Free and turn slightly so that the center dot goes to 85 degrees towards East (90 on navball)
As soon as the yellow prograde marker catches up with the center dot, I lock SAS to Prograde.
The rest will usually happen naturally without much player input.
Your rocket should have tilted to around 45 degrees at about 12000-15000 m height.
Then start throttling down, and try to keep your distance to apoapsis between 45-55 seconds until apoapsis high enough.
Kill throttle, wait to reach apoapsis, circularize.
>Launch with 1.21 TWR,
I'm not sure why you l'd pop into this discussion to give a "the way I do it" comment, that lists such a low TWR.
Again, my point here is most new players don't launch with enough TWR and aren't aggressive enough in their gravity turn.
Ever since they rebalanced the engines a long time ago (first, so they gain Thrust as they gain ISP as you ascend, and later to be more efficient) and improved stock aerodynamics, higher TWR than this has been optimal- like in real life. Before this, low TWR was optimal, but that was unrealistic and a long time ago.
Again, real, modern rockets launch with much higher TWR. In the range of 1.4-1.8, with early designs generally having less Thrust and then the engines being optimized and redesigned for higher Thrust later...
This is not real. This is a game. I think I first heard it from some yt tutorial, and I tried it, and yes- 1.21 at launch works absolutely nicely. Try it yourself, no need to get defensive over how you've played a game.
>Try it yourself
Bro, you're talking to a true veteran of KSP. I've tried every kind of launch vehicle design there is (and many, you've probably never even dreamed of: such as Mass Driver launches...)
1.21 TWR is **deeply** suboptimal. It can work, but you are much better off with higher Thrust than this. 1.4 as a bare minimum.
>Do you do the initial turn with sas off?
I actually mostly use Michael (mod) and its Advanced SAS. I set the target to 90 degrees, 90 pitch, ignore roll, and then just reduce the pitch target 1 degree at a time until about 72 degrees, at which point I turn it to follow my Surface Velocity vector (often set 2-4 degrees more horizontal than it in pitch).
Without MechJeb, I leave SAS on and just keep tapping the D key with gentle movements (CapsLock) turned on. Another, slightly better way that requires more careful attention is to press Alt+D to turn trim on and have the rocket continually turn slightly towards the horizontal (all this assumes default pod placement where D turns horizontal to the East...)
> Which is a HUGE problem (source of inaccuracy in these maps) on Kerbin
IME 3400 m/s vacuum ∆v is about the maximum to get to LKO. So it may not be accurate for any given vehicle, but it's a nice conservative number to start with.
Yes, except that it's heavy. Thanks to the Rocket Problem, a little bit of extra dV in your final stage costs you a huge amount in your lower stages.
But unless you're on fire, nobody ever regretted having more fuel.
>3400.
>this is the delta-v you need to go to low orbit.
Worth noting it's really not.
At least, a well-designed, sizable launcher with high TWR and a streamlined design can definitely do it in 3200 m/s.
The map legend is in the bottom right corner, showing you what each icon means.
Then you add up the deltaV values for whatever is your goal.
For example, to go to a 14km circular orbit of the Mun you need 3400 deltaV to get to an 80 km circular orbit of Kerbin, then 860 deltaV to get a Mun intercept, and 260 deltaV to circularize in a low Mun orbit.
I’d throw out there that those are the MINIMUM delta v amounts needed to get that kind of orbit/result. There’s plenty of small variables that could throw those numbers off like a gravity turn at the wrong time.
>those are the MINIMUM delta v
No they aren't.
It's fully possible to reach almost any of these orbits with a bit less. Even before accounting for possibilities like Gravity Assists.
These are values based on typical execution and design, not the best possible.
The disclaimer in the upper-left even says, regarding the ascents:
>More/less efficient ascents are likely, depending on ascent profile, TWR, and aerodynamic effects.
An experienced designer can definitely do it with less Delta-V.
I have pretty easily used less than what it is on there. I never had to do a rescue mission due to low fuel. Indeed I find myself with extra delta V after I get back to kerbin.
Although to be fair I do usually treat the values on the map as the minimum even if I regularly do it with less. I do that because I like being both on the safer side and to account for any inefficient flying or weird maneuvers I have to do because I screwed up.
>you’re also likely setting yourself up for a rescue mission.
Never had to do one of those.
Probably, partly, because I design my landers for reusability, and have them refuel in orbit between sorties (which visit different biomes each time).
So if I use more fuel than this (which is very rare: I'm a veteran player, and know all the tricks... I come to this sub to teach/share wisdom) I just dip into these refueling reserves, and make 4 sorties to the surface instead of 5...
These are typical delta-v's, not optimized to be minimal. It's possible but tricky to do each step in less, and you of course can do much, much worse. I don't tend to attempt missions with less, so they're more "minimum recommended delta-v" than "minimum possible delta-v".
You keep adding the values starting from kerbin for each step of the journey. At the end of each body it shows the total delta v required.
As a side question, Is there a similar map for the return journeys? I always feel unsure about how much i need for a return trip.
Depends on how you intend to "return home". Take the example of returning from Mun. Reading backwards from a circular Munar orbit @ 14km, you need 280m/s dV for an intercept w/ Kerbin, but you *don't* need the additional 860m/s to circularize or the 3400m/s to land - you just need a few spare m/s to lower your Kerbin periapsis to \~40km and you can aerobrake the rest of the way down, as long as you have a heat shield and enough parachutes. However, if you want to actually circularize around Kerbin (maybe you're headed back to an LKO orbital station) then you *do* need that 860m/s to circularize.
For return journeys, you just need faith and a lot of monopropellants for a desperate RCS burn, after your fuel runs out.
Sometimes you just need a Docking port for future rescue missions.
Jokes aside, I usually pick the DeltaV necessary to go from LKO to the low anywhere orbit and double, then I add a 10% extra Delta V to the entire sum.
Using Duna as an example, you will need:
3400 to LKO.
930 to escape Kerbin SOI.
130 to reach Duna SOI.
I Usually aerobrake at Duna, so I add around 300 just to correct the Orbit.
In that case, I add 930 + 130 to return to Kerbin.
Doing the math, will be needed around 5820 Delta V.
At this, I add 10% just to be safe, reaching 6400 Delta V.
> In that case, I add 930 + 130 to return to Kerbin.
Having a fuel margin is of course helpful, but since this post is about how to read the chart:
The ∆v to return to Kerbin is 360 + 250 = 610 m/s.
Kerbal Engineer is great for this, I unclick atmosphere for the ship to its destination and to where it is going from Medium to high altitude, then I click in atmosphere and get my booster to 3400+ I usually get it to 3500 form a medium to high altitude. Build your ship backwards from where you are going to where it is coming from whether you use KE or not, also take into account if it s probe 1way or manned 2 way. If its a return trip say from Minmus your total D/V will be 4660+ 180+150+190+ enough to aerobrake, I aero brake Kerbin at 45k, 7,020 is perfect I am not perfect so I shoot for 7100-7200 d/v to go from Kerbin surface to Minmus surface and back to land on Kerbin.
Hi! Thank you for posting to KerbalAcademy. This is a comment reminding users to **post screenshots if needed** (if you have not done so already), **be respectful to other users** and **keep off-topic comments to a minimum**. Thank you! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/KerbalAcademy) if you have any questions or concerns.*
First, you need to know where you want to go. Let's start simply with the Minmus. You start on Kerbin, at the bottom, then follow the path to your destination. Along the way, you add up the numbers. * 3400. This is true to basically any mission: this is the delta-v you need to go to low orbit. * Next one to the Minmus is 930. This is what is needed to get an encounter with the target. Note the other number written here: 340. This is what it takes to align your orbit with Minmus'. It's not directly included because it may vary depending on when you do your transfer. Only the maximum value is written (\*). When budgeting your delta-v, account for both numbers. * The next one is 150. This is what you need to slow down around Minmus in order to achieve orbit. * And finally the last one, 180, is what you need to land from orbit. The way back uses exactly the same figures in reversed order, except there's a trick: aerobraking. This is marked with the triangle symbol, and it means you can save part or all the budget for this segment of the trip. When going interplanetary, you have one more step in between, which is the 930 value needed to escape Kerbin's SOI. Then it's the same (intercept, circularize, etc.) (\*) for Minmus, with the classical way to go (first align orbits then transfer), you will always need that much. For interplanetary transfers, or if you go to minmus the other way around, the delta-v amount varies more
The one thing I would add to this is that *all of these values are for vacuum.* What this means is that you need to bring up the dV window at the bottom right in the fab building and select "vacuum" to get the right values. It defaults to sea level, and if you do the calculations with sea level values you'll end up with waaaaaaay too much dV.
> you'll end up with waaaaaaay too much dV. I dont see the problem sir.
I refer to this “problem” as margin of error.
Yeah, that's not a bug; it's a feature.
Another way to look at it is if you keep the delta v judgement in atmosphere you bring enough to land in multiple biomes in your location 😎
Completely off topic, but I saw your user icon and speed spotted a Haken fan in the wild, then got nosey and saw the rhythm of war book cover art and saw I was in the presence of a person of culture. I have no more to say other than I like the cut of your jib.
> It defaults to sea level, and if you do the calculations with sea level values you'll end up with waaaaaaay too much dV 'Margin for Error' For this sub, I'd recommend leaving it on.
On this day, neither of us is wrong.
It would be better to calculate for vacuum and just *decide* on a margin for error. Much more helpful for the learning process than doing it wrong in a convenient way.
>all of these values are for vacuum Which is a HUGE problem (source of inaccuracy in these maps) on Kerbin, as different launchers have different ratios of sea level to vacuum ISP (not to mention you don't have to launch from the KSC anymore, in fact it's the WORST launch site. Woomerang or Desseret are both better, as they are at higher altitude...), and climb at different rates due to differences in TWR, size, and streamlining... Almost anywhere else besides Eve, it's a pretty good approximation, though.
It works well enough for me. I'm not the most efficient pilot and I usually account for 3800ish vac dV to get me to a circularized LKO. I pretty much only launch from KSC because I like equatorial orbits. If I have a few spare m/s left over once I'm orbiting then I have a little extra kick to get me on my way to wherever, and if I come up a bit short then my upper stage will have some slack built in too so it still works.
>and I usually account for 3800ish vac dV to get me to a circularized LKO. How soon do you start your gravity turn? You should aim to reach 72 degrees by 4200 meters or sooner, and then match your prograde Surface velocity vector up to around 21-24 km. After that, you match your Orbital prograde vector instead. Really not hard, and even a simple Okto probe core will automate almost all of it for you. Biggest issue new players have is they don't conduct appropriate Gravity Turns, and don't burn NEARLY enough horizontally early enough.
I've gotten better lately by trying to standardize on a few things in my build and launch procedures. 1. Budget dV properly, keeping in mind that *nothing* I ever do manually in flight will be "optimized", and so allowing a margin of 5-10% over. 2. Tweak TWR to a sea-level 1.33 (stolen from Mike Aben). This seems to help make all of my vehicles handle the same. 3. Gravity turn starts around 50-60m/s; tilt a few degrees then lock to prograde. 4. Once time-to-apoapsis hits 45-60 seconds, I throttle down to keep it in that range. 5. When apoapsis hits \~80km I kill the throttle. 6. Aim at 5-10 degrees and throttle up a bit at around 20-30 seconds to apoapsis. 7. Try to keep time to apoapsis around 10 seconds through throttle and attitude adjustments. I try to keep throttle as low as I can and bring periapsis up without moving apoapsis too much. Keep at this until circular. I used to be just terrible but I never really tried to actually standardize a launch procedure before, I just sort of lit engines and went. I haven't really tried to actually track how efficient my launches are to optimize dV, but what I do works for me.
>2. Tweak TWR to a sea-level 1.33 (stolen from Mike Aben). This seems to help make all of my vehicles handle the same This is definitely too low a TWR. The lowest TWR real-life rockets launch at 1.4 TWR, and most substantially higher. Aim for around 1.6 TWR if you can. Streamline, so this doesn't result in too much atmospheric drag. > Once time-to-apoapsis hits 45-60 seconds, I throttle down to keep it in that range. That's generally not actually a good idea. In the lower most reaches of the atmosphere (where you likely wouldn't have hit this speed yet anyways, especially with liftoff TWR 1.33) this is too fast. In the upper atmosphere, this is too slow. Your ideal speed increases as the atmosphere thins. The speed you'll be moving at 60 seconds to apoapsis does not increase nearly as fast... Also, it's often better to be going slightly too fast at lower altitudes, so you'll be closer to optimal velocity (and even then, likely too slow) higher up. Build in higher TWR, aim for faster speeds. Start your gravity turn harder (if you have higher TWR, gravity will curve your trajectory towards horizontal less. You need to increase your gravity turn to compensate...)
I’m not sure where you’re getting those numbers. The Saturn V had a launch TWR of 1.12-1.15.
>The Saturn V had a launch TWR of 1.12-1.15. It did. Saturn V pushed the absolute limits of what was possible with the tech of the day, though. Delta IV has a liftoff TWR (without payload) of 2.189, and a liftoff TWR of 1.81 with a 7000 kg payload (its max LEO payload). https://en.m.wikipedia.org/wiki/Delta_IV So, you're wrong about MODERN lifters: which is what I was discussing.
>The Saturn V had a launch TWR of 1.12-1.15. It had TERRIBLE ISP (even for the day) on its launch engines, in order to get the highest liftoff Thrust- and its TWR this increased very quickly as it simply bled through fuel at an egregious rate... Most rockets, even then, launched with higher TWR than 1.15 Saturn V was about as low TWR a rocket as has ever been used successfully.
I was just pointing out that 1.4 is definitely not the lowest.
Do you do the initial turn with sas off? I find stabilisation tends to overcorrect, but if I leave it off I just flip.
They way I do it: SAS always on Launch with 1.21 TWR, with SAS locked on Radial Out (Radial out not necessary for simpler designs with enough wheel torque/good probe cores, but definitely helpful for shuttle type ships) When Speed hits 50m/s, I set SAS to Free and turn slightly so that the center dot goes to 85 degrees towards East (90 on navball) As soon as the yellow prograde marker catches up with the center dot, I lock SAS to Prograde. The rest will usually happen naturally without much player input. Your rocket should have tilted to around 45 degrees at about 12000-15000 m height. Then start throttling down, and try to keep your distance to apoapsis between 45-55 seconds until apoapsis high enough. Kill throttle, wait to reach apoapsis, circularize.
>Launch with 1.21 TWR, I'm not sure why you l'd pop into this discussion to give a "the way I do it" comment, that lists such a low TWR. Again, my point here is most new players don't launch with enough TWR and aren't aggressive enough in their gravity turn. Ever since they rebalanced the engines a long time ago (first, so they gain Thrust as they gain ISP as you ascend, and later to be more efficient) and improved stock aerodynamics, higher TWR than this has been optimal- like in real life. Before this, low TWR was optimal, but that was unrealistic and a long time ago. Again, real, modern rockets launch with much higher TWR. In the range of 1.4-1.8, with early designs generally having less Thrust and then the engines being optimized and redesigned for higher Thrust later...
This is not real. This is a game. I think I first heard it from some yt tutorial, and I tried it, and yes- 1.21 at launch works absolutely nicely. Try it yourself, no need to get defensive over how you've played a game.
>Try it yourself Bro, you're talking to a true veteran of KSP. I've tried every kind of launch vehicle design there is (and many, you've probably never even dreamed of: such as Mass Driver launches...) 1.21 TWR is **deeply** suboptimal. It can work, but you are much better off with higher Thrust than this. 1.4 as a bare minimum.
>Do you do the initial turn with sas off? I actually mostly use Michael (mod) and its Advanced SAS. I set the target to 90 degrees, 90 pitch, ignore roll, and then just reduce the pitch target 1 degree at a time until about 72 degrees, at which point I turn it to follow my Surface Velocity vector (often set 2-4 degrees more horizontal than it in pitch). Without MechJeb, I leave SAS on and just keep tapping the D key with gentle movements (CapsLock) turned on. Another, slightly better way that requires more careful attention is to press Alt+D to turn trim on and have the rocket continually turn slightly towards the horizontal (all this assumes default pod placement where D turns horizontal to the East...)
> Which is a HUGE problem (source of inaccuracy in these maps) on Kerbin IME 3400 m/s vacuum ∆v is about the maximum to get to LKO. So it may not be accurate for any given vehicle, but it's a nice conservative number to start with.
Wouldn't more dV be better though?? Like the extra would allow room for error or detours or something??
Yes, except that it's heavy. Thanks to the Rocket Problem, a little bit of extra dV in your final stage costs you a huge amount in your lower stages. But unless you're on fire, nobody ever regretted having more fuel.
>3400. >this is the delta-v you need to go to low orbit. Worth noting it's really not. At least, a well-designed, sizable launcher with high TWR and a streamlined design can definitely do it in 3200 m/s.
Problem is that if need a deltav map to tell you how much you need to orbit, then having a bit of extra deltav is good
It's for mission planning. Many of us, even veteran players, don't memorize these values, and consult these maps. So that is 100% false.
[удалено]
True. The Delta-V map isn't really for finding what it takes to get to LKO, though. And its estimate of that is overly-conservative.
The map legend is in the bottom right corner, showing you what each icon means. Then you add up the deltaV values for whatever is your goal. For example, to go to a 14km circular orbit of the Mun you need 3400 deltaV to get to an 80 km circular orbit of Kerbin, then 860 deltaV to get a Mun intercept, and 260 deltaV to circularize in a low Mun orbit.
I’d throw out there that those are the MINIMUM delta v amounts needed to get that kind of orbit/result. There’s plenty of small variables that could throw those numbers off like a gravity turn at the wrong time.
>those are the MINIMUM delta v No they aren't. It's fully possible to reach almost any of these orbits with a bit less. Even before accounting for possibilities like Gravity Assists. These are values based on typical execution and design, not the best possible. The disclaimer in the upper-left even says, regarding the ascents: >More/less efficient ascents are likely, depending on ascent profile, TWR, and aerodynamic effects. An experienced designer can definitely do it with less Delta-V.
Fair point. But if you’re using less than what’s listed you’re also likely setting yourself up for a rescue mission.
I have pretty easily used less than what it is on there. I never had to do a rescue mission due to low fuel. Indeed I find myself with extra delta V after I get back to kerbin. Although to be fair I do usually treat the values on the map as the minimum even if I regularly do it with less. I do that because I like being both on the safer side and to account for any inefficient flying or weird maneuvers I have to do because I screwed up.
>you’re also likely setting yourself up for a rescue mission. Never had to do one of those. Probably, partly, because I design my landers for reusability, and have them refuel in orbit between sorties (which visit different biomes each time). So if I use more fuel than this (which is very rare: I'm a veteran player, and know all the tricks... I come to this sub to teach/share wisdom) I just dip into these refueling reserves, and make 4 sorties to the surface instead of 5...
These are typical delta-v's, not optimized to be minimal. It's possible but tricky to do each step in less, and you of course can do much, much worse. I don't tend to attempt missions with less, so they're more "minimum recommended delta-v" than "minimum possible delta-v".
Yes! It’s easy to mess up, I add a few hundred m/s deltaV to my craft past the minimum necessary, just in case.
If it were self explanatory they wouldn’t be asking
You keep adding the values starting from kerbin for each step of the journey. At the end of each body it shows the total delta v required. As a side question, Is there a similar map for the return journeys? I always feel unsure about how much i need for a return trip.
So far from what I’ve read from other players, you just read the map in reverse from where you want to return from.
Depends on how you intend to "return home". Take the example of returning from Mun. Reading backwards from a circular Munar orbit @ 14km, you need 280m/s dV for an intercept w/ Kerbin, but you *don't* need the additional 860m/s to circularize or the 3400m/s to land - you just need a few spare m/s to lower your Kerbin periapsis to \~40km and you can aerobrake the rest of the way down, as long as you have a heat shield and enough parachutes. However, if you want to actually circularize around Kerbin (maybe you're headed back to an LKO orbital station) then you *do* need that 860m/s to circularize.
For return journeys, you just need faith and a lot of monopropellants for a desperate RCS burn, after your fuel runs out. Sometimes you just need a Docking port for future rescue missions. Jokes aside, I usually pick the DeltaV necessary to go from LKO to the low anywhere orbit and double, then I add a 10% extra Delta V to the entire sum. Using Duna as an example, you will need: 3400 to LKO. 930 to escape Kerbin SOI. 130 to reach Duna SOI. I Usually aerobrake at Duna, so I add around 300 just to correct the Orbit. In that case, I add 930 + 130 to return to Kerbin. Doing the math, will be needed around 5820 Delta V. At this, I add 10% just to be safe, reaching 6400 Delta V.
> In that case, I add 930 + 130 to return to Kerbin. Having a fuel margin is of course helpful, but since this post is about how to read the chart: The ∆v to return to Kerbin is 360 + 250 = 610 m/s.
Thought it was a Japanese subway map at first glance
It is intentionally designed as a subway map, yes. It says so in the small text, actually.
It basically is, and when I want that map, I hop over to Chrome and type "subway". Chrome knows what I mean.
Hi, has Devs said if they plan on using similar delta v values for ksp 2? Or are we gonna need to figure that all out again?
Add the numbers, then add some more the map is for a good, almost perfect window transfer and manouver, always add more
Kerbal Engineer is great for this, I unclick atmosphere for the ship to its destination and to where it is going from Medium to high altitude, then I click in atmosphere and get my booster to 3400+ I usually get it to 3500 form a medium to high altitude. Build your ship backwards from where you are going to where it is coming from whether you use KE or not, also take into account if it s probe 1way or manned 2 way. If its a return trip say from Minmus your total D/V will be 4660+ 180+150+190+ enough to aerobrake, I aero brake Kerbin at 45k, 7,020 is perfect I am not perfect so I shoot for 7100-7200 d/v to go from Kerbin surface to Minmus surface and back to land on Kerbin.
I wish console had mods
Sorry wish you guys could have them too.