IMFD AppE Navigation Checklists

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IMFD Appendix D: Summary Of Programs IMFD Manual Contents IMFD Appendix F: The Major Do’s and Don’t’s of IMFD with secrets to make your life easier


IMFD Appendix E - Checklists

These are brief checklists designed for quick reference. To see any one in more detail, please see the section in which the checklist is described (these are written in much more detail). The playback files can be downloaded with these links:

Course Setup (Off Plane, Planet to Planet)

Example: Set up an Earth to Mars Transfer

  • Open IMFD
  • Select Course
  • Select Target Intercept. Since we are traveling from a planet to another planet, this is our navigation tool of choice.
  • Set Target as Mars because this is where we are going.
  • Check Reference is Sun and Source is Earth because the Sun is orbited by both the Earth and Mars (Reference), and we are leaving Earth (Source).
  • Check that the Transfer Mode is Off-Plane. This is the easiest way to get there.
  • In Target Intercept, Lock TOF. This is so that when we adjust TEj, TIn will adjust at the same rate, keeping our time of flight constant.
  • Advance TEj until dV is minimized (I use 10x adjustments on the MJD to advance one day per click).
  • Unlock TOF
  • Adjust TIn to minimize dV
  • Alternately adjust TEj and TIn to further minimize the dV.
  • Use scenario editor (or time warp) to advance time until one week before launch (for distant windows, also stop one month prior to launch)
  • Again, alternately adjust TEj and TIn to adjust for inaccuracies in original predictions

(IMFD gets more accurate over shorter times, so dV will have changed a bit)

  • Fast forward to launch.
  • Return to normal time when TEj says 10,000. That is the approximate number of seconds that you will be in orbit around Earth before you leave for Mars (gives you plenty of time to circularize your orbit, align planes, etc.)
  • Congratulations! You have a flight plan to Mars.

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Course Setup (Off Plane, Moon to Moon) — Playback 3

Example: Set up an Io to Callisto Transfer

  • Open IMFD
  • Select Course
  • Select Target Intercept. Since we are traveling from a moon to another moon, this is our navigation tool of choice.
  • Set Target as Callisto
  • Check Reference is Jupiter and Source is Io because Jupiter is orbited by both the Io and Callisto (Reference), and we are leaving Io (Source).
  • Check that the Transfer Mode is Off-Plane. This is the easiest way to get there.
  • In Target Intercept, Lock TOF. This is so that when we adjust TEj, TIn will adjust at the same rate, keeping our time of flight constant.
  • Advance TEj until dV is minimized (I use 10x adjustments on the MJD to advance one day per click).
  • Unlock TOF
  • Adjust TIn to minimize dV
  • Alternately adjust TEj and TIn to further minimize the dV.
  • Use scenario editor (or time warp) to advance time until one week before launch (for distant windows, also stop one month prior to launch)
  • Again, alternately adjust TEj and TIn to adjust for inaccuracies in original predictions (IMFD gets more accurate over shorter times, so dV will have changed a bit)
  • Fast forward to launch.
  • Return to normal time when TEj says 10,000. That is the approximate number of seconds that you will be in orbit before you leave for Callisto (gives you plenty of time to circularize your orbit, align planes, etc.)
  • Congratulations! You have a flight plan to Callisto.

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Course Setup (Off Plane, Planet to Moon) — Playback 2

Example: Set up an Earth to Moon Transfer

  • Open IMFD
  • Select Course
  • Select Target Intercept. Since we are traveling from a planet to a moon, this is our navigation tool of choice.
  • Set Target as Moon. Once you do this, the purple orbit will begin to "swivel," shrinking and growing continually.
  • Set TEj to 0. This will stop it from shrinking and growing.
  • Check that the Reference is Earth (because this is the object that the target and source are orbiting around) and check that the Source is your spacecraft (in a Planet to Moon Transfer, the source must be yourself).
  • Set the TIn to your desired time until intercept PLUS 6000 seconds. A good value for this would be 400,000 seconds. This six thousand seconds should be under TEj, but a bug causes the orbit to shrink and grow unless TEj is set to zero. So, we must account for the 6000 seconds in the TIn.
  • Go to the Surface Launch Program.
  • Hilight the Course item and hit + until it says Lunar Off-Plane. This is the mode of surface Launch you must use when you do a Planet to Moon transfer.
  • Input Moon as the Target (it will prompt you to do so when Lunar Off-Plane is selected).
  • Wait for Time to reach zero, and take off, and enter orbit. You are ready for your orbit ejection!

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Course Setup (Off Plane, Moon to Planet) — Playback 4

Example: Set up Moon to Earth Transfer

  • Open IMFD
  • Select Planet Approach. Since this is a moon to planet flight, we must use planet approach.
  • Set the Source to Moon. The display should now change. We did this because we are leaving from the Moon.
  • Check Target Equator and Reference Earth. The Earth is the thing that the source and target are moving around (Reference) and the target is the Equator so we can set the inclination with respect to the equator, which makes things easier.
  • You can set up desired values of your Earth orbit (PeA, Equitorial inclination, etc.) but this is not completely necessary.
  • Congratulations! You have planned a Moon to Earth Transfer.

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Course Setup (Planar Transfer, Planet to Planet) — Playback 5

Example: Set up an Earth to Mars Transfer

  • Open IMFD
  • Select Course
  • Select Target Intercept. Since we are traveling from a planet to another planet, this is our navigation tool of choice.
  • Set Target as Mars because this is where we are going.
  • Check Reference is Sun and Source is Earth because the Sun is orbited by both the Earth and Mars (Reference), and we are leaving Earth (Source).
  • Check that the Transfer Mode is either Target Plane, Two Plane, or Source Plane. It is recommended that you use Two Plane or Source Plane, not Target Plane.
  • In Target Intercept, Lock TOF. This is so that when we adjust TEj, TIn will adjust at the same rate, keeping our time of flight constant.
  • Advance TEj until dV is minimized (I use 10x adjustments on the MJD to advance one day per click).
  • Unlock TOF
  • Adjust TIn to minimize dV
  • Alternately adjust TEj and TIn to further minimize the dV.
  • Use scenario editor (or time warp) to advance time until one week before launch (for distant windows, also stop one month prior to launch)
  • Again, alternately adjust TEj and TIn to adjust for inaccuracies in original predictions (IMFD gets more accurate over shorter times, so dV will have changed a bit)
  • Fast forward to launch.
  • Return to normal time when TEj says 10,000. That is the approximate number of seconds that you will be in orbit before you leave for Mars (gives you plenty of time to circularize your orbit, align planes, etc.)
  • Congratulations! You have a flight plan to Mars.

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Course Setup (Planar Transfer, Moon to Moon)

Example: Set up an Io to Callisto Transfer

  • Open IMFD
  • Select Course
  • Select Target Intercept. Since we are traveling from a moon to another moon, this is our navigation tool of choice.
  • Set Target as Callisto
  • Check Reference is Jupiter and Source is Io because Jupiter is orbited by both the Io and Callisto (Reference), and we are leaving Io (Source).
  • Check that the Transfer Mode is either Target Plane, Two Plane, or Source Plane. It is recommended that you use Two Plane or Source Plane, not Target Plane.
  • In Target Intercept, Lock TOF. This is so that when we adjust TEj, TIn will adjust at the same rate, keeping our time of flight constant.
  • Advance TEj until dV is minimized (I use 10x adjustments on the MJD to advance one day per click).
  • Unlock TOF
  • Adjust TIn to minimize dV
  • Alternately adjust TEj and TIn to further minimize the dV.
  • Use scenario editor (or time warp) to advance time until one week before launch (for distant windows, also stop one month prior to launch)
  • Again, alternately adjust TEj and TIn to adjust for inaccuracies in original predictions (IMFD gets more accurate over shorter times, so dV will have changed a bit)
  • Fast forward to launch.
  • Return to normal time when TEj says 10,000. That is the approximate number of seconds that you will be in orbit before you leave for Callisto (gives you plenty of time to circularize your orbit, align planes, etc.)
  • Congratulations! You have a flight plan to Callisto.

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Surface Launch — Playbacks 2,3,4,5,6,7

Example: Launch to Low Earth Orbit before going to Mars. Note that this assumes you have completed some type of Earth to Mars Transfer setup.

  • Open IMFD
  • Select Surface Launch. Since we are on the ground launching to LEO, Surface Launch is the Program of choice.
  • Check that it says Course-Program in the top right hand corner. This means that the program will gather data from the Course Program.
  • Set the Altitude to the altitude that you want your orbit to be at. For Earth, it should be above 200k, and for Mars, above 100k. This is to avoid an orbit inside the atmosphere.
  • Time warp slowly until the time says about 300s (5 minutes to takeoff), and return to normal time.
  • Prepare your vessel for takeoff.
  • When it hits zero, engage main engines and take off. Fly the heading that the Surface Launch Program displayed as Hed.
  • Introduce nose side slip to keep EIn as low as possible. This saves us from using fuel trying to fix it later.
  • Perform MECO when in orbit.
  • Contratulations! You are in orbit ready to go!

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Orbit Eject — Playbacks 3,4,5,6,7

Example: Eject from Earth Orbit to go to Mars. This assumes that you have completed some type of Earth to Mars Transfer setup AND you have launched into a low earth orbit.

  • Open IMFD
  • Open the Orbit Eject Program. We are in orbit, ready to eject, so this is the program of choice.
  • Highlight the item in the top right hand corner and change it from Higher-Orbit to Course. We want Orbit Eject receiving data from the Course Program.
  • Hit the NXT button and change from Realtime to Off-Axis. Since this is a long duration burn, Off-Axis mode is the method of choice.
  • Now time warp until you hit a node. Turn Orbit Normal or Orbit Anti-normal, and engage main engines. Note that IMFD does not tell you which way to turn, so you must guess. Your goal is to get EIn down to zero, because this is Eject Inclination and we want it as low as possible. When it is zero, MECO.
  • Now time warp until you are about a third of an orbit away from your eject point (solid green line is about a third of an orbit away from the dotted green line), return to normal time, and hit Autoburn.
  • Time Warp to 100x. Autoburn will slow down time, and execute the burn.
  • Leave the Orbit Eject program up.
  • Congratulations, you are on your way to Mars!

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Leaving a Planet’s SOI — Playbacks 1,3,4,5,6,7

Example: Eject from Earth Orbit to go to Mars. This assumes that you have completed some type of Earth to Mars Transfer setup, you have launched into a low earth orbit, AND you have ejected from Low Earth Orbit.

  • IMFD should be open, and set to the Target Intercept Program.
  • IMFD should be open on the other side too, with the Orbit Eject Program running.
  • When the Orbit Eject Program displays a message that says ―Have a nice voyage!‖ set the source in the Target Intercept to Program (SRC input ―x‖ without the quotations) and hit MNU to change the MFD with Orbit Eject to Map Program.
  • Time warp carefully until dV hits a low point and starts increasing again, and then hit Autoburn to execute your first Midcourse Correction (All in the MFD with Target Intercept).
  • Congratulations! You have left a planet‘s SOI!

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Midcourse Correction — Playbacks 1,2,3,4,5,6,7

Example: Perform a midcourse correction en route to Mars from Earth. This assumes that you have completed some type of Earth to Mars Transfer setup, you have launched into a low earth orbit, AND you have ejected from Low Earth Orbit.

  • IMFD should be open, and set to the Target Intercept Program.
  • Check that Source is set to Self.
  • Hit the Autoburn Button.
  • Congratulations! You have made a midcourse correction!

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Midcourse Correction Special Case — Plane Change Maneuver — Playbacks 5,6,7

Example: Perform a plane change maneuver en route to Mars from Earth. This assumes that you have completed some type of Earth to Mars Planar Transfer setup, you have launched into a low earth orbit, you have ejected from Low Earth Orbit, AND you are well out of the Earth‘s SOI.

  • IMFD should be open, and set to the Target Intercept Program.
  • You should see a number, Tn (Time to Node). Time warp until you are about 1800s (about half an hour) away from the Node.
  • Scroll down to Prep. PlC using the NXT and PRV buttons.
  • Hit the + button. This turns on Prep. PlC, and the course program begins to prepare for the plane change maneuver.
  • Hit Autoburn, and time warp to 100x. Let Autoburn do the rest.
  • Congratulations! You have just completed your plane change maneuver!
  • Note that now that you have done your plane change maneuver, the Target Intercept Program will act as if it were in Off-Plane Mode.

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Planet Approach Setup — Playbacks 6,7

Example: Set up your approach to Mars. You should have a PeT of about 400,000 seconds (get this value from the Map Program!!!)

  • Open IMFD.
  • Select the Planet Approach Program. Since you are approaching a planet but not doing a direct landing or direct reentry, this is the program of choice.
  • Set the Reference to Mars. This tells the program that you are approaching Mars.
  • Set the Target to Equator. This allows us to use Equatorial Inclination as opposed to Ecliptic Inclination, making our lives easier.
  • Use NXT and PRV, and +, -, or SET to set values for your PeA (Altitude of Periapsis) and EqI (Equatorial Inclination) to what you desire. You must set EqI to a latitude higher than the base you intend to land on, if you intend to land.
  • Execute the Autoburn Button.
  • Congratulations! You are now approaching Mars!
  • Now, you must time warp slowly and keep an eye on dV. It will start to increase. Every once in a while, hit Autoburn again (maybe every time it gets above 100). Careful as it increases at a dramatic rate as you get close to the planet.

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Orbit Insert — Playbacks 1,2,3,4,5,6,7

Example: Perform a capture burn to enter low Mars orbit. You should have a PeT of about 1800 seconds and be approaching Mars with a hyperbolic orbit (Eccentricity greater than 1). Since we are close to the planet, most MFD‘s will have an accurate prediction of PeT, and you do not NEED to use the Map Program for this prediction (You can use Orbit MFD).

  • Open IMFD V 4.2.1. You must use this version of IMFD for Orbit Insert!!! The later versions (5.0, 5.3, etc) do not work very well.
  • In IMFD 4.2.1, Select the Course button. The Orbit Insert Program is located here.
  • Select Orbit Insert. TtB should be less than 1800 seconds, as you are nearing your periapsis.
  • Set desired ApD (Radial Distance of Apoapsis) OR Eccentricity. When you change one, the other one also changes. For a perfectly circular orbit, just set Eccentricity (Ecc) to zero. You cannot control your PeA (Altitude of Periapsis).
  • Engage Autoburn.
  • Time warp to 100x. Let Autoburn slow time automatically (which it will do, don‘t worry) and let it perform the burn. Watch dV.
  • When the engines shut off, there will probably still be some dV left. Switch to Burn Vector View by hitting the BV button, rotating towards the grey cross, and engaging main engines until dV nears zero.
  • Congratulations, you are in low orbit!!

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Base Approach Setup — Playbacks 1,3,4,5,6

Example: Set up your approach to Olympus Base. You should have a PeT of about 500,000 seconds (get this value from the Map Program!!!)

  • Open IMFD.
  • Select the Base Approach Program. Since we are approaching a planet and we want to land at a particular base, Base Approach is the program of choice.
  • Hit the TGT button, and set the Target to Olympus. This will automatically input Olympus‘s Longitude and Latitude.
  • Set Alt to 120k. Mars‘s atmosphere ends at 100k, but we want to give ourselves some room for error.
  • Set up the Num item. This is the number of full orbits between orbit insert and landing. See the description of this item in the Base Approach Program section.
  • Hit Autoburn.
  • Congratulations! You are now approaching Mars, headed for a landing at Olympus!
  • Now, you must time warp slowly and keep an eye on dV. It will start to increase. Every once in a while, hit Autoburn again (maybe every time it gets above 100). Careful as it increases at a dramatic rate as you get close to the planet.

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Map Program Setup — Playbacks 3,4,5,6,7

Example: Set up the Map Program en route to Mars.

  • Open IMFD.
  • Select the Map Program.
  • Set Reference as Sun.
  • Set Target as Mars.
  • Set Center as what you want centered (your ship, periapsis at mars, etc.)
  • Hit SOI. This will display the SOI around all bodies with a mass greater than the mass limit in the configuration page.
  • Hit Dsp. This will display all orbits. If you do not want to see all orbits, then do not hit this button.
  • Hit the INT button. This will turn on intercept mode.
  • The map is now set up to go to Mars. Note that none of these steps are absolutely necessary, but it‘s nice to have a good display as your ship travels through the Solar System.

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Slingshot Setup — Playbacks 6,7

Slingshot setups are very tricky and are different for every scenario. The two slingshot playbacks should cover most situations you will encounter.

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Circularize Orbit

Example: Circularize your orbit around Earth. This assumes you are in a closed (Eccentricity less than 1) orbit and you are currently at the altitude that you want your orbit to be at.

  • Open IMFD.
  • Select the Orbital Program.
  • Hit the CIR button to open the Orbit Circularization Mode.
  • Hit the Autoburn button.
  • You are now in a circular orbit.

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Match Velocity — Playback 2

Example: You are approaching Phobos at about 50 m/s, and you want to match its velocity so you stay in the same position relative to the Martian Moon.

  • Open IMFD.
  • Select the Orbital Program.
  • Hit the VeM button to open the Velocity Match Mode.
  • Hit the TGT button and type in Phobos.
  • Hit the Autoburn button.
  • You now have the same relative velocity as Phobos.

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Direct Ascent to the Moon — Playback 1

Example: Start at Cape Canaveral, and set up and execute one long burn for a direct ascent to the moon.

  • Open IMFD.
  • Select the Course Program.
  • Select the Target Intercept Program. Since we are going from a planet to a moon, Target Intercept is the program of choice.
  • Set Target as Moon. Once you do this, the purple orbit will begin to ―swivel,‖ shrinking and growing continually.
  • Set TEj to 0. This will stop it from shrinking and growing. Also, since this is a direct ascent, time between takeoff and ejection burn is zero because it is one long combined burn.
  • Check that the Reference is Earth (because this is the object that the target and source are orbiting around) and check that the Source is your spacecraft (in a Planet to Moon Transfer, the source must be yourself).
  • Set the TIn to your desired time until intercept. A good value for this would be about 400,000 seconds.
  • Open Burn Vector View. Once the ship is in a stable state, time warp at about 10,000x until the cross goes SIGNIFICANTLY ABOVE the horizontal green line (more than one third of the way from the horizontal green line to the top of the circle). We have now found our launch window. We will be flying with our nose pointed towards this cross, and if the cross is below the horizontal green line (which is the horizon line), we will be burning our engines for several minutes towards Earth. Not a good idea.
  • Take off, and fly towards the cross. Keep the cross grey (not green) and in the center of the crosshairs.
  • When your Total dV remaining reaches around 5,000, cut off your main engines and hit the Autoburn Button. Let Autoburn take care of the rest of the burn.
  • Congratulations! You are on your way to the Moon!

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IMFD Appendix D: Summary Of Programs IMFD Manual Contents IMFD Appendix F: The Major Do’s and Don’t’s of IMFD with secrets to make your life easier