Overview
On The Surface of Giants is a mission that frequently stumps those who have finally managed to beat Vesta Overkill and thought it would finally be downhill from there.Orbital mechanics is not the most straightforward thing under ordinary circumstances, let alone when it involves low polar orbits around gas giants, where even reaching target is hard, and orbit phasing likes to unexpectedly get deadly.This guide shows how to complete Surface of Giants using:* stock modules only* conventional cannons only* general purpose ships* retrograde interceptsAnd beat the mission without:* missiles* drones* hilariously OP workshop stuff (any)* orbit phasing* dumping your ships and crews into Neptune – seriously, that’s kind of messed up thing to do – even in between sessions of casual nuking and assorted warcrimes
Preface
On The Surface of Giants is a mission that frequently stumps those who have finally managed to beat Vesta Overkill and thought it would finally be downhill from there.
Orbital mechanics is not the most straightforward thing under ordinary circumstances, let alone when it involves low polar orbits around gas giants, where even reaching target is hard, and orbit phasing likes to unexpectedly get deadly.
This guide shows how to complete Surface of Giants using:
- stock modules only
- conventional cannons only
- general purpose ships
- retrograde intercepts
And beat the mission without:
- missiles
- drones
- hilariously OP workshop stuff (any)
- orbit phasing
- dumping your ships and crews into Neptune – seriously, that’s kind of messed up thing to do – even in between sessions of casual nuking and assorted warcrimes
Of course, retrograde intercepts can also unexpectedly get deadly, but that’s what just happens when you involve yourself in a bizarre crossover between drive-by shooting and a game of chicken, both at around 33km/s.
No one said having fun is going to be easy. Or safe.
Ships
The mass budget for this mission is 11kt.
Most of that is going to be propellant, however.
You’re going to need a small combat ship – up to maybe kiloton, with good delta-v reserve (over 4km/s is absolutely necessary, 6 should be quite comfrotable). The rest of the budget is going to be tanker(s).
Both need to have high acceleration – for combat ship 1.5-2.5G full is a good ballpark estimate, for tanker 0.3G full should work out well.
High acceleration is crucial for impulsive burns in low orbits around Neptune and also for dodging propellant depot incoming at over 30km/s.
Conventional (turreted) cannons should suffice as weapons, custom modules are also not necessary.
You can build your ships or use someone else’s – for example mine:
Tanker:
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Assorted light combat ships (pick one):
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Set-up
Before doing anything it’s important to give your combat ship(s) orders:
- Order should probably be broadside, although that depends on your ship configuration
- Any drop-tanks should NOT detach automatically when empty
- Weapons should ignore range
Departure
You should schedule your departure burn for when your fleet will be crossing depot’s orbital plane.
Switching your frame of reference to depot should show you interesting points on your trajectory as orbital nodes:
Select the relevant point and switch back to Neptune frame of reference for actually setting up the burns to avoid dealing with spaghetti:
The depot might be in low orbit, but you actually want to burn prograde (relative to Neptune) and RAISE your apoapsis first.
Given that target’s orbit is orthogonal to your own and low around very massive object, Hohman transfer would need completely insane amounts of delta-v and accelerations – so you’ll perform a bi-elliptic transfer instead.
There is a tradeoff here – the more you raise your apoapsis, the less delta-v you’ll use later on, but the more time it will cost you.
A burn short of 2km/s should put your apoapsis somewhere around the orbit of Triton and leave you with enough time to complete the mission.
This should be possible to execute without leaving orbit around Polyphemus, if not, you can always push off gently first and continue scheduling you burns as normal.
Suicide
Once underway, find (using depot’s frame) another node near apoapsis (and of-course switch back to Neptune afterwards – see why below):
Now, schedule braking (retrograde) burn – you want to come to a dead stop in your trajectory and start falling straight down towards Neptune:
It’s imperative you actually kill all your velocity at the right moment – you need to be falling straight down, crossing depot’s orbital path. Any velocity you haven’t cancelled and any distance you miss the depot’s path are going to be something you pay for with sweat, tears and quite possibly blood later, so if you need to correct the trajectory do it as early as possible:
Congratulations!
You are now falling straight down onto Neptune and are going to die.
Your combat ship is probably more or less out of delta-v now as well – well done!
Dodging the Planet
If you followed the instructions so far, you should now be falling onto Neptune and towards your certain death with little, if any, delta-v remaining in your combat ship’s tanks – which is pretty much par for the course as far as heeding the advice from randos on internet is concerned – seriously, what did you expect? Was there any time you didn’t end up falling into Neptune?
Now, you will need to tackle one of those problems first in order to tackle the other – that’s why you brought a tanker:
Once full again schedule an out of plane burn that just barely allows you to avoid collision.
For this guide you are going end up in retrograde orbit relative to the depot, but if you wanted to do “normal”, prograde intercept you could just burn in the opposite direction:
Your trajectory back at the apoapsis will probably show over time limit, but you are not going to be returning to the apoapsis.
Final Destination
The next part is going to be rather intense so you will need as much delta-v as possible. This is why you held onto those tanks and this why you will need to refuel now:
Now, schedule a braking (retrograde) burn at periapsis. Even with high acceleration the burn will take a while so start before periapsis and try to time it so that it’s more or less symmetrical in regards to it.
Depending your delta-v you will probably not be able to approximately match the depot’s orbit in one go but the lower you get, the more time you save. Refuel in between braking burns.
Eventually you’ll probably drain your tanker’s delta-v and will need to separate from it.
It’s probably nicer to not run it completely dry and make it burn prograde at apoapsis to not crash into Neptune.
Uh, you are coming back for those guys, right?
Now back to your combat ship – finish depot’s orbit on your last pass through periapsis – you can probably do it automatically now:
Which means you are now more or less on collision course with the depot. Oops.
Orbital Chicken and Murder-Suicide (without suicide – hopefully)
Now that you are hurtling towards the depot you might want to do some minor trajectory adjustments.
It’s probably better to err towards prograde (to pass over the depot on a rising trajectory) and make it so that perpendicular velocity reaches minimum and then starts rising again (if it rises from the beginning you are overshooting the depot from get go). You want it to be low in general too:
If you miss your intercept or intercept too far/with too much perpendicular velocity to get firing solution, you get another one free half an orbit later, but you might need to perform orbit corrections to get a better intercept and not crash into Neptune. Your first insitnct should be to adjust prograde, only if it doesn’t work, try other directions.
Once you do intercept, target specifically the crew radiator on top of CM (by clicking on it in the 3D view, NOT on the left hand panel):
Your ship should start firing while performing any necessary evasive manoeuver (disable any spinal guns you have before the shooting starts – trying to aim them might lock you into collision trajectory until too late – and you have seconds at most):
And that’s it.
Mission accomplished.
Wait, you didn’t die?
Weird.
