ultimate guide to the kerbal space program

74
Version: 0.23.5 – 0.24(ish) WernherVon Kerman

Upload: mot-schmeal

Post on 26-Dec-2015

68 views

Category:

Documents


16 download

DESCRIPTION

Kerbal Space Program Guide

TRANSCRIPT

Page 1: Ultimate Guide to the Kerbal Space Program

Version: 0.23.5 – 0.24(ish)

Wernher Von Kerman

Page 2: Ultimate Guide to the Kerbal Space Program

Lovingly Dedicated to:

Jebediah Kerman

Bob Kerman

Bill Kerman

The Team at Squad.

"We who are about to die, salute you."

The Kerbonaut’s Guide to the Galaxy.

1 st Edition

Page 3: Ultimate Guide to the Kerbal Space Program

Before you start: It is recommended that you laminate

this guide. When you see a “” You should leave

a tick/cross in DRY WIPE marker according to your current situation.

Failure is always an option. Good luck and have fun exploring the

Kerbolar System

Page 4: Ultimate Guide to the Kerbal Space Program

KSP Basics:

Delta-V - In astrodynamics a Δv or delta-v (literally “change in velocity”) is a measure of the amount of the effort that is needed to change from one trajectory to another by making an orbital manoeuvre.

L”X”O – Low “Enter Planet Name Here” Orbit. For example, LKO = “Low Kerbin Orbit.”

Escape Velocity – The velocity required to exit a planet’s sphere of influence.

Periapsis (Pe) – The lowest point in your orbit.

Apoapsis (Ap) – The highest point in your orbit.

Prograde/Retrograde – Prograde is “forward relative to the direction of movement” it will increase your orbital velocity.Retrograde is “backwards relative to the direction of movement” it will decrease your orbital velocity.

Navball – Used to get your bearings and to navigate when in space.

Thrust-To-Weight-Ratio – TWR for short is a ratio that defines the power of a craft's engines in relation to its own weight. If a craft needs to get into a stable orbit or land safely

Page 5: Ultimate Guide to the Kerbal Space Program

on the current celestial body without using parachutes, then its engines must put out more thrust than its current weight to counteract gravity. In the terms of a ratio, a craft with a greater thrust than weight will have a TWR greater than 1.

Inclination - The tilt of the orbit is given by the inclination. Usually the value is given in degrees where the value is given between –90° and 270°. An inclination of 0° or 180° is equatorial, so the craft is always above the equator.

Navball Point of Reference - As all movement in space is relative, the point of reference determines the object from which all distance measurements and velocity vectors are made. Clicking this area will toggle the point of reference between Surface and Orbit, as indicated by the green text. If a target is selected, there is a third option, Target. Changing the point of reference changes the location of the prograde and retrograde markers.

Manoeuvre Nodes - A maneuver node is a planned velocity change along an orbit. Multiple maneuver nodes can be added which will affect the following maneuver nodes. After adding a node it shows the velocity change needed to reach the next new orbit next to the navball.

Manoeuvre Node Directions –

Prograde/Retrograde - These vectors directly change the speed of the craft. Burning prograde will increase velocity, raising the altitude of the orbit on the other side, while burning retrograde will decrease velocity and reduce the orbit altitude on the other side.

Normal/Anti-Normal - The normal vectors are orthogonal to the orbital plane. Burning normal or anti-normal will change the orbital inclination. On the navball the normal and anti-

Page 6: Ultimate Guide to the Kerbal Space Program

normal vectors are located on the equator line directly between the prograde and retrograde markers.

Radial in/Radial out - The radial-in vector points directly toward the center of the orbited body (center of the brown hemisphere on the navball), while the radial-out vector points directly away from it (center of the blue hemisphere). Performing a radial burn will rotate the orbit around the craft like spinning a hula hoop with a stick. Radial burns are the least efficient way of adjusting one's path - it is much more effective to use prograde and retrograde burns.

Navball Icons

Page 7: Ultimate Guide to the Kerbal Space Program

Centre of:Mass – “The centre of mass, abbreviated CoM, or centre of gravity, is the location of an object where all mass is equally distributed around it. It is important to balance

a craft to prevent it from getting out of control. Planes should have a centre of mass slightly in front of the centre of lift. For all craft the thrustvector should point to, point away from or go through the centre of mass.” – Kerbal Space Program Wiki

Centre of Mass (Yellow)

Centre of Thrust (Pink)

Thrust – “The centre of thrust or thrustvector is the direction in which the thrust is acting and on which point the thrust acts on the craft. The thrustvector and centre of mass should

be in one line to minimize steering.” – Kerbal Space Program Wiki

Lift – “The centre of lift is used mainly when creating planes, it shows the axis and direction of lift provided by wings, control surfaces and winglets. Inside the editor it is showed as a cyan-coloured sphere (axis) along with an arrow (direction of the lift). The centre of lift should also always be behind the centre of mass.”– Kerbal Space Program Wiki

Page 8: Ultimate Guide to the Kerbal Space Program

Kerbin

“A unique world, Kerbin has flat plains, soaring mountains and wide, blue oceans. Home to the Kerbals, it has just the right conditions to support a vast, seemingly undepletable population of the eager green creatures.” –Kerbal Astronomical Society”

Planetary Characteristics: ΔV Stats (LKO):Sphere Of Influence: 84,159.3km Body: Delta-V:Atmosphere Present: Yes Mun ~860m/sOxygen Present: Yes Minmus ~930m/sAtmospheric Height: 69,077m Eve ~1033m/sSurface Gravity: 9.81m/s (1G) Duna ~1060m/sEscape Velocity: 3,431m/s Moho ~1676m/sΔV To LO from Sea Lvl: ≈4500 m/s Jool ~1915m/sSynchronous Orbit: 2868.75km Eeloo ~2100m/sPe for Aerobrake(Suggested): ≈36,000m KEO ~1120m/sScience Multiplier:Surface: 0.4Atmospheric: 0.7Space: 1

Page 9: Ultimate Guide to the Kerbal Space Program

Mun

“The Muns discovery is widely regarded as one of the more important breakthroughs of Kerbal evolution. Granted it didn’t happen all that long ago, but it’s still fair to say that Kerbals are wiser and more evolved now than they were back then.” –Kerbal Astronomical Society

Characteristics: Mun Biomes: Sphere Of Influence: 2429.6km Biome: Atmosphere Present: No MidlandsOxygen Present: No Midlands CratersAtmospheric Height: N/A HighlandsSurface Gravity: 1.63m/s (0.166G) Highland CratersEscape Velocity: 807.08m/s CanyonsΔV To Low Orbit: ≈800m/s Northern BasinSynchronous Orbit: N/A (SoI too low) East CraterPe for Aerobrake(Suggested): N/A Northwest CraterScience Multiplier: Southwest CraterSurface: 4 Farside CraterAtmospheric: N/A East Farside CratersSpace: 3 Polar Crater

PolesPolar Lowlands

Page 10: Ultimate Guide to the Kerbal Space Program
Page 11: Ultimate Guide to the Kerbal Space Program

Minmus

“Minmus is the smallest moon orbiting Kerbin. From the surface of Kerbin, it can be seen on clear days as a tiny blue speck in the sky.”-Kerbal Astronomical Society

Planetary Characteristics: Minmus Biomes:Sphere Of Influence: 2,247.4km Biomes:Atmosphere Present: No HighlandsOxygen Present: No MidlandsAtmospheric Height: N/A LowlandsSurface Gravity: 0.491m/s (0.05G) SlopesEscape Velocity: 242.61m/s Lesser FlatsΔV To Transfer: 920m/s FlatsΔV To LO from Sea Lvl: N/A Great Flats Synchronous Orbit: 357.94km Greater FlatsPe for Aerobrake(Suggested): N/A PolesScience Multiplier:Surface: 5Atmospheric: N/ASpace: 4

Page 12: Ultimate Guide to the Kerbal Space Program
Page 13: Ultimate Guide to the Kerbal Space Program

Eve

“Eve is certainly the purplest object in the solar system. Its one of the larger, most visible objects, mainly because of its very, very purple tint.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats*:Sphere Of Influence: 85,109.4km Body: Delta-V:Atmosphere Present: Yes Kerbin ~1030m/sOxygen Present: No Moho ~810m/sAtmospheric Height: 96,708m Duna ~190m/sSurface Gravity: 16.7m/s (1.7G) Dres ~430m/sEscape Velocity: 4831.96m/s Jool ~1045m/sΔV To LO From Sea Lvl: ≈11,500 m/s Eeloo ~1230m/sSynchronous Orbit: 10,328.47km Gilly ~1650m/sPe for Aerobrake(Suggested): ≈72,500m LEO ~12000m/sScience Multiplier: Kerbol Orbit ~80m/sSurface: 12Atmospheric: 7Space: 7

*(From Orbit Around Eve + Does not include getting into orbit or landing)

Page 14: Ultimate Guide to the Kerbal Space Program

Duna

“Also known as the red dot that you can see if you squint at it really hard, Duna has long been a wonder to Kerbalkind.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats *:Sphere Of Influence: 47,921.9km Body: Delta-V:Atmosphere Present: Yes Ike ~270m/sOxygen Present: No Eve ~190m/s

Atmospheric Height: 41,446m Dres ~460m/sSurface Gravity: 2.94m/s (0.3G) Kerbin ~1060m/sEscape Velocity: 1372.41m/s Moho ~840m/sΔV To LO from Sea Lvl: ≈1750 m/s Jool ~1075m/sSynchronous Orbit: 2880.00km Eeloo ~1260m/sPe for Aerobrake(Suggested): ≈13,000m LDO ~1380m/sScience Multiplier: Kerbol Orbit ~110m/sSurface: 8Atmospheric: N/ASpace: 7

*(From Orbit Around Duna + Does not include getting into orbit or landing)

Page 15: Ultimate Guide to the Kerbal Space Program

Dres

“Dres is a very small planet. It was the first planet considered to be a dwarf. Its orbit is highly irregular and together with its size it took a long time to discover since half the time it was not where scientists expected to find a planet.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats *:Sphere Of Influence: 32,832.8km Body: Delta-V:Atmosphere Present: No Eve ~430m/sOxygen Present: No Duna ~460m/sAtmospheric Height: N/A Jool ~1315m/sSurface Gravity: 1.13m/s (0.115G) Kerbin ~1300m/sEscape Velocity: 558.00m/s Moho ~1080m/sΔV To LO from Sea Lvl: ≈555 m/s Eeloo ~1500m/sSynchronous Orbit: 732.24km LDO ~800m/s**

Pe for Aerobrake(Suggested): N/A Kerbol Orbit ~350m/sScience Multiplier:Surface: 8Atmospheric: N/ASpace: 7

*(From Orbit Around Dres + Does not include getting into orbit or landing)

**(Delta-V needed to get into orbit after ascent)

Page 16: Ultimate Guide to the Kerbal Space Program

Moho

“Moho figures in Kerbal mythology as a fiery place with oceans of flowing lava. In reality however, its much less interesting.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats *:Sphere Of Influence: 9,646.7km Body: Delta-V:Atmosphere Present: No Eve ~810m/sOxygen Present: No Duna ~840m/sAtmospheric Height: N/A Jool ~1695m/sSurface Gravity: 2.70m/s (0.275G) Kerbin ~1680m/sEscape Velocity: 1,161.41m/s Dres ~1080m/sΔV To LO from Sea Lvl: ≈1,400 m/s Eeloo ~1500m/sSynchronous Orbit: N/A (SoI too Low) LMO ~2200m/s**

Pe for Aerobrake(Suggested): N/A Kerbol Orbit ~730m/sScience Multiplier:Surface: 9Atmospheric: N/ASpace: 8

*(From Orbit Around Moho + Does not include getting into orbit or landing)

**(Delta-V needed to get into orbit after ascent)

Page 17: Ultimate Guide to the Kerbal Space Program

Jool

“Jool is particularly known for being a rather large, predominantly green planet. Kerbalkind has longed to visit it since it was first spotted in the sky. Philosophers reason that the swirling green planet must be a really nice place to visit, on account of its wholesome coloration.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats *:Sphere Of Influence: 2.4559852×109 m Body: Delta-V:Atmosphere Present: Yes Eve ~1045m/sOxygen Present: No Duna ~1075m/sAtmospheric Height: 138,155km Moho ~1695m/sSurface Gravity: 7.85m/s (0.8G) Kerbin ~1915m/sEscape Velocity: 9,704.43m/s Dres ~1315m/sΔV To LO from Sea Lvl: ≈22,000 m/s Eeloo ~2115m/sSynchronous Orbit: 15,010.46km LJO ~2630m/s**

Pe for Aerobrake(Suggested): N/A Kerbol Orbit ~965m/sScience Multiplier:Surface: N/AAtmospheric: 7Space: 7

*(From Orbit Around Jool + Does not include getting into orbit or landing)

**(Delta-V needed to get into orbit after ascent)

Page 18: Ultimate Guide to the Kerbal Space Program
Page 19: Ultimate Guide to the Kerbal Space Program

Eeloo

“There’s been a considerable amount of controversy status of Eeloo as being a proper planet or just a lump of ice going around the sun. The debate is still ongoing, as most academic summits held to address the issue have devolved into, on good days, petty name calling, and on worse ones, all-out brawls.”–Kerbal Astronomical Society

Planetary Characteristics: ΔV Stats *:Sphere Of Influence: 119,082.94km Body: Delta-V:Atmosphere Present: No Eve ~1230m/sOxygen Present: No Duna ~1260m/sAtmospheric Height: N/A Moho ~1880m/sSurface Gravity: 1.79m/s (0.172G) Kerbin ~2100m/sEscape Velocity: 841.83m/s Dres ~1500m/sΔV To LO from Sea Lvl: ≈840m/s Jool ~2115m/sSynchronous Orbit: 683.69km LEO ~2100m/s**

Pe for Aerobrake(Suggested): N/A Kerbol Orbit ~1150m/sScience Multiplier:Surface: 9Atmospheric: N/ASpace: 8

*(From Orbit Around Eeloo + Does not include getting into orbit or landing)

**(Delta-V needed to get into orbit after ascent)

Page 20: Ultimate Guide to the Kerbal Space Program

Time Warp Altitudes

Delta-V Map

Page 21: Ultimate Guide to the Kerbal Space Program
Page 22: Ultimate Guide to the Kerbal Space Program

Airplane Construction (By Keptin)

Page 23: Ultimate Guide to the Kerbal Space Program
Page 24: Ultimate Guide to the Kerbal Space Program
Page 25: Ultimate Guide to the Kerbal Space Program
Page 26: Ultimate Guide to the Kerbal Space Program

VAB Checklist*

Booster: Fuel Engines SRB’S Decouplers Struts! Control Surfaces Correct Staging Action Groups LES (Launch Escape System)

Orbital Stage: RCS Monopropellant Fuel Engine (LV-909/Poodle) Batteries Solar Panels/Reactor Docking Port

Lander/Descent Stage: Landing Legs Ladder Lights Parachutes Command Module S.A.S/Reaction Wheels

Page 27: Ultimate Guide to the Kerbal Space Program

More RCS and Monopropellant Fuel Engine (LV-909/Poodle) Batteries Solar Panels Crew (Jeb, Bill, Bob) Science (Goo, Materials) Clear Hatch Snacks!

*Some parts may not be available if you play in Career mode.

Page 28: Ultimate Guide to the Kerbal Space Program

Rocket Construction ToolsPresuming that you’ve already built your first rocket (If not, whack a RT-10 Solid Fuel Booster onto a Command Pod Mk1 and launch!) These are tools designed to help make more efficient rockets:

Page 29: Ultimate Guide to the Kerbal Space Program

Apologies for not having 0.23.5 rockets, there are no graphs available on the internet including these. I’m working on making my own.

Page 30: Ultimate Guide to the Kerbal Space Program

To use this nomogram, pick a dV on the left and Isp on the right. Draw a straight line between them. The required mass fraction of your vehicle/stage is where your line crosses the Mass Fraction scale.

Page 31: Ultimate Guide to the Kerbal Space Program

Do the same as before, choose your desired payload weight on the left and your mass fraction which you obtained beforehand and draw a straight

Page 32: Ultimate Guide to the Kerbal Space Program

line between them. This is the amount of fuel you will need to lift the payload, the dry fuel tanks and fuel.

You Done Goofed!Check That:

Hatch isn’t obstructed! Landing leg orientation is correct! You have enough electricity! You have strutted EVERYTHING! You have sufficient fuel supplies! You have crew! Action groups are set up! You have science modules! Parachutes for landings!

Page 33: Ultimate Guide to the Kerbal Space Program

Mission Planner:

Mission Name:

Budget: /

Contracts:

Science Goal: +

Mission Briefing:

Chosen Crew Member(s):

Launch Vehicle:

Orbital Vehicle:

Lander:

Page 34: Ultimate Guide to the Kerbal Space Program

Launch Date:

Flight Checklist:Pre-Launch:

S.A.S Staging Crew Damage Check 5P’s: Pods: Command Modules, Habitats etc. Propulsion: Fuel and Engines Power: Panels, Batteries, Reactors Piloting: RCS, S.A.S etc. People: Crew, (If using TAC) Food, Water

etc.

Launch: Increase Throttle Activate First Stage

Ascent Stage: Jettison SRB’s At 7.5-10km, Complete Gravity Turn Continue To Burn Until Desired Apoapsis

is Reached

Orbital Stage: Burn Pro-Grade until the Periapsis is

within 0-3km of the Apoapsis Height

Page 35: Ultimate Guide to the Kerbal Space Program

Deploy Solar Panels Do Science Perform Transfer Stage OR Burn Retro-

Grade to return to Kerbin.

Pre-Landing (When Returning or Landing Anywhere): Retract Solar Panels and Antenna Deploy Legs Arm Parachutes Crew Check Select Landing Area

Post Landing: Do Science! Stretch Legs! Recover Vehicle (If landed on Kerbin)!

Page 36: Ultimate Guide to the Kerbal Space Program

Flight Observations/Notes:

Page 37: Ultimate Guide to the Kerbal Space Program

Orbit Guide

1) Build a rocket. It should have enough Delta-V to get into LKO. A minimalistic rocket would be:Command Pod Mk1FL-T400 Fuel TankLV-909 Liquid Fuel EngineTR-18A Stack DecouplerFL-T800 Fuel TankLV-T30 Liquid Fuel Engine

2) Turn SAS on and throttle up3) Countdown from 10.4) Press Space to launch and wait until you are at 10,000m,

ensure that you head directly up (Keep your dot on the blue top dot on the Navball)

5) Jettison your first stage with the spacebar6) Throttle down to 2/3rd power7) Turn 45 degrees East (Press D) and burn until your apoapsis

is at 70-75km. You can check this by pressing M.8) As you approach apoapsis, orient your ship to the 0-degree

latitude mark (Directly East) between the blue and brown halves of the navball.

9) Once you are 10-30 seconds away from apoapsis, begin your orbital burn by using the Shift key to throttle up. You can go at full throttle or partial throttle, but you may overshoot when at full throttle.

10) Wait until a periapsis appears directly opposite to your apoapsis and wait until it’s altitude becomes >70km. Hit X to turn off your engines instantly.

11) Congratulations, you have made orbit!

Page 38: Ultimate Guide to the Kerbal Space Program

Docking Tutorial Courtesy of Leforian

1. Time your launch by putting the target slightly behind KSC in its orbit like this.

2. As you are burning start your gravity turn at the normal altitude.

3. In orbital view try to get your apoapsis to meet the target's orbit ahead of the target.

4. The tricky part is determining where to put the apoapsis. You can make it encounter sooner by burning more vertically, and encounter later by burning more horizontally.

5. I misjudged the timing and my apoapsis crossed the orbit too late.

Page 39: Ultimate Guide to the Kerbal Space Program

The top red carrot is where I will be, and the bottom carrot is where my target will be. I need to push my apoapsis farther away. Remember that burning directly prograde will raise your apoapsis further, so you will also have to burn slightly down in pitch to keep your apoapsis at the altitude you need.

6. After moving my apoapsis forward for a minute or two I get a good 100 meter-ish encounter.

Page 40: Ultimate Guide to the Kerbal Space Program

Formula Sheet “For when you feel like Wernher Von Kerman”

Thrust to Weight Ratio –

Ft - Engine Thrust

M – Total mass of the craft

g – The local gravitational acceleration

Combined Specific Impulse –

If the Isp is the same for all engines in a stage, then the Isp is equal to a single engine. If the Isp is different for engines in a single stage, then use the equation above.

Tsiolkovsky rocket equation –

Basic Δv Calculation – Δv - the velocity change possible in m/s

Page 41: Ultimate Guide to the Kerbal Space Program

Mstart - the starting mass in the same unit as Mend

Mend - the end mass in the same unit as Mstart

Isp – the specific impulse on the engine in seconds.

Fuel flow rate –

Orbital velocity –µ - Gravitational Parameter of parent body (km3/s2)r – Radius of orbit (km)

Notes Page

Page 42: Ultimate Guide to the Kerbal Space Program
Page 43: Ultimate Guide to the Kerbal Space Program

Science Modules:

Mystery Goo™ Containment Unit:“The Mystery Goo™ Containment Unit is a science part used to expose a goo to atmospheres and vacuum in attempts to gain science from observing the goo inside. This can be achieved either via action group or right clicking the container and clicking observe mystery goo. The unit cannot be reused after its results were transmitted, unless it is cleaned via the Mobile Processing Lab MPL-LG-2. Like EVA

reports, the science gained from observing the Mystery Goo varies depending on different conditions in flight.” – Kerbal Space Program Wiki

SC-9001 Science Jr.“Science Jr. is the more advanced scientific sensor. It is used to retrieve science points and to complete science experiments in space or other celestial body. The unit cannot be reused after its results were transmitted, unless it is cleaned by theMobile Processing Lab MPL-LG-2.” – Kerbal Space Program Wiki

PresMat Barometer:“Displays atmospheric pressure to five significant figures, while active. A pressure below 0.0001 is shown as vacuum by the sensor. Lower atmospheric

Page 44: Ultimate Guide to the Kerbal Space Program

pressures markedly reduce lift and drag induced by the atmosphere, and cause a small change in engine efficiency.” – Kerbal Space Program Wiki

GRAVMAX Negative Gravioli Detector:“This instrument shows the gravity in your current sphere of influence to a maximum of 4 significant figures and two decimal places. This can be used with altitude to estimate the mass of the nearest celestial body or to measure its surface gravity. Alternatively, it can be used with the accelerometer and altitude to make landing estimates.” – Kerbal Space Program Wiki

2HOT Thermometer:“The 2HOT Thermometer displays temperature to 5 significant figures when activated and right-clicked. There is no unit shown but it is assumed to be degrees Celsius. The 2HOT cannot be used to earnscience while distant from a celestial body, although it will continue to tell the temperature.” – Kerbal Space Program Wiki

Mobile Processing Lab MPL-LG-2:

“The Mobile Processing Lab MPL-LG-2 allows scientific data to be transmitted with higher efficiency and to reuse the Mystery Goo™ Containment Unit andSC-9001 Science Jr. after transmitting their result. The module needs its full capacity of two Kerbals to work. Note that it is not a command module;

Page 45: Ultimate Guide to the Kerbal Space Program

any craft it's a part of will need a probe body or command pod to be piloted. Using the module consumes electricity” – Kerbal Space Program Wiki

Easy Science At Kerbin:Gather a:

Crew Report! EVA Report! Surface Sample! Mystery Goo! Materials Bay!

Kerbin Biomes: Launchpad Runway KSC Mountain Shores Tundra Water Grasslands Desert Badlands Highlands Ice Caps

Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over Flying Over

Page 46: Ultimate Guide to the Kerbal Space Program

Interplanetary Travel Orbital Transfer Guide 10 Year Launch Window Calendar (Earth

Years) Gravity Assists Delta-V Requirements Travelling To Duna, Mun and Minmus Landing and Parachutes

KSC

Page 47: Ultimate Guide to the Kerbal Space Program

Interplanetary Travel Orbital Transfer Guide 100 Year Launch Window Calendar

(Kerbin Years) Landing Guides Transfer Windows Gravity Assists Delta-V Requirements Ideal Interplanetary Phase Angles

Page 48: Ultimate Guide to the Kerbal Space Program

Orbital Transfer GuideIn map view, put the blue cross on the planet you’re orbiting and the red cross on your

rocket. The point where the green line intersects your desired planet's orbit is where you want it to be when you start your transfer burn.

Page 49: Ultimate Guide to the Kerbal Space Program

Hohmann & Bi-Elliptical Transfers

Hohmann Transfer:

A Hohmann transfer is a technique that involves burning your engine twice whilst in orbit in order to reach a higher orbit.

You start off by burning prograde at your periapsis until you reach the desired altitude for your apoapsis. You will now have an elliptical orbit. Next you have to travel up to your apoapsis and burn prograde once again in order to raise your periapsis to the same altitude as your apoapsis. Like so:

Bi-Elliptical Transfer:

A Bi-Elliptical transfer is similar to a Hohmann transfer although it requires one extra step. Most of the time the Hohmann technique is more useful but in some cases using a Bi-Elliptical transfer can save you Delta-V!

You start a Bi-Elliptical transfer by burning prograde from your periapsis in order to

Page 50: Ultimate Guide to the Kerbal Space Program

raise your apoapsis. Again, making an ellipse. Once you are at apoapsis, you burn prograde to raise your periapsis to your desired orbital altitude. After travelling to periapsis, you want to burn retrograde and bring your apoapsis down to roughly the same altitude as your periapsi. Like so:

Landing GuidesYou’ve come this far; let’s not screw it up now!

Check your parachutes:

Page 51: Ultimate Guide to the Kerbal Space Program

Atmospheric Targeting Graph/Guide:

Page 52: Ultimate Guide to the Kerbal Space Program

Aerocapture Graphs:

250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 300025000

30000

35000

40000

45000

50000

55000

Kerbin SOI Entry Aerocapture Chart

MinmusMunSync OrbitSSync Orbit1000 km100 km

Orbital Velocity (m/s)

Aero

capt

ure

Peria

psis

(m)

Page 53: Ultimate Guide to the Kerbal Space Program

250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 300055000

57000

59000

61000

63000

65000

67000

69000

71000

73000

75000

Eve SOI Entry Aerocapture Chart

Sync OrbitSSync Orbit1000 km100 km

Orbital Velocity (m/s)

Aero

capt

ure

Peria

psis

(m)

250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 30008000

9000

10000

11000

12000

13000

14000

15000

16000

17000

18000

Duna SOI Entry Aerocapture Chart

IkeSync OrbitSSync Orbit100km50km

Orbital Velocity (m/s)

Aero

capt

ure

Peria

psis

(m)

Page 54: Ultimate Guide to the Kerbal Space Program

250500

7501000

12501500

17502000

22502500

27503000

32503500

37504000

100000

105000

110000

115000

120000

125000

130000

135000

Jool SOI Entry Aerocapture Chart

PolBopTyloVallLaytheSync OrbitSSync Orbit1000 km150 km

Orbital Velocity (m/s)

Aero

capt

ure

Peria

psis

(m)

250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 300020000

22000

24000

26000

28000

30000

32000

34000

Laythe SOI Entry Aerocapture Chart

SSync Orbit1000 km100 km

Orbital Velocity (m/s)

Aero

capt

ure

Peria

psis

(m)

Page 55: Ultimate Guide to the Kerbal Space Program

Transfer WindowsYears 1 -25

Page 56: Ultimate Guide to the Kerbal Space Program

Years 26 -50

Page 57: Ultimate Guide to the Kerbal Space Program

Years 51 – 75

Page 58: Ultimate Guide to the Kerbal Space Program

Years 76 -100

Page 59: Ultimate Guide to the Kerbal Space Program

Gravity Assists:“A gravity assist is a maneuver in which you use a flyby of a secondary celestial body (such as a

planet or moon) to alter your orbit about the primary (typically the sun, but occasionally a planet: for instance, when navigating the Joolian moon system). Gravity assists are useful because they allow

you to gain or lose orbital energy or make expensive maneuvers such as plane changes for free; however, they are difficult to set up and require careful planning and lots of patience. That said, once

you master them, you can manage feats you wouldn't have thought possible.” –Stochasty

1. Firstly, you have to put yourself into a transfer orbit, ensuring that the celestial body is travelling in the direction you want to go in.

2. Time Accelerate until you reach the SoI of the celestial body.3. Plan another course correction manoeuvre at Periapsis to increase your

Apoapsis height after leaving the SoI, it is most effective when you are closer to the body, but ensure you won’t collide with anything and that you won’t be accidentally aerobraking.

4. Time Accelerate until you leave the SoI of the celestial body.5. When you check the map you will notice that your Apoapsis height has

increased.

Page 60: Ultimate Guide to the Kerbal Space Program

6. You can repeat this, changing your course when furthest away from the body you are getting a gravity assist from, until you have reached a the SoI of another planet or anywhere really.

7. You can use gravity assists to go from Kerbin to Duna, or Jool to Kerbin without using a lot of fuel. It is one of the most efficient ways of interplanetary travel but is also one of the hardest manoeuvres.

8. You can perform a powered gravity assist. Accelerating at your periapsis has the greatest effect on your apoapsis. This still applies to your periapsis during a gravity assist. When you accelerate during your fly-by, fuel is used very efficiently to increase the apoapsis of your final trajectory. This is a very difficult technique because it is hard to control your final trajectory even when using a manoeuvre node but can save a lot of time and a lot of fuel.

Delta-V Requirements:(To Low Orbit)

Mün: ~5620m/s

Minmus: ~5550m/s

Moho: ~8430m/s

Eve: ~6890m/s (And Gilly: ~8750m/s)

Duna: ~5980m/s (And Ike: ~6360m/s)

Page 61: Ultimate Guide to the Kerbal Space Program

Dres: ~6650m/s

Jool: ~9095m/s

Pol (From LJO): ~3400m/s

Bop (From LJO): ~3380m/s

Tylo (From LJO): ~3130m/s

Vall (From LJO): ~2760m/s

Laythe (From LJO): ~2380m/s

Eeloo: ~8750m/s

Page 62: Ultimate Guide to the Kerbal Space Program
Page 63: Ultimate Guide to the Kerbal Space Program