Transfer MFD

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Revision as of 14:23, 16 December 2024 by Arvil (talk | contribs) (Transfer MFD mode.)
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Transfer MFD mode is used for calculating transfer orbits between celestial bodies., or any object with different orbits.

Buttons and Hot Keys

  • REF Shift+R}: Opens a menu list of celestial bodies to select one as reference body.
  • SRC Shift+S: Opens a menu list of celestial bodies or vessels to select one as source body.
  • TGT shift+T: Opens a menu list of celestial bodies or vessels to select one as target.
  • NT Shift+N: Unselect target.
  • HTO Shift+X: Toggle HTO (hypothetical transfer orbit) display on or off.
  • NUM {Key|Shift}}+M: Toggle numerical multi-body trajectory calculation.
  • UPD Shift+U: Update numerical trajectory, is one is displayed.
  • STP Shift+Z: Enter number of time steps.
  • EJ- Shift+,: Decrease orbit ejection longitude.
  • EJ+ Shift+.: Increase orbit ejection longitude.
  • DV- Shift+-: Decrease ejection velocity difference.
  • DV+ Shift+equals key: Increase ejection velocity difference.

Display

  • Transfer:Indicates this is the Transfer MFD mode.
  • Ref:: Reference body or ship.

Source section, upper left

  • Src: Source orbit, usually [self].
  • TrL: True longitude of your ship, or source body.

Target section, upper right

  • Tgt: Target body or ship.
  • TrL: True longitude of target.
  • TLi: True longitude at time of interception.

HTO section, left

  • TLe: True longitude at the time of orbit ejection.
  • DTe: Time remaining until orbit ejection.
  • Dv: DeltaV to achieve transfer orbit.
  • TLi: True longitude at the time of interception.
  • DTi: Time remaining until interception.

Num orbit secton, right

  • Stp: During calculation, this will display the number of steps the calculator has taken.
  • T: Time in seconds the calculator estimates will have past during the calculations.

Inclination section, lower left

  • RInc: Shows relative inclination between the source and target orbits, if it's too much it will be red, go back to Align MFD to realign orbits.


Transfer MFD display looks similar to that of the Orbit MFD display, displays a source and target orbit, relative to an orbit reference which can also be selected.

Source orbit

The source orbit is the orbit that your ship is leaving in order to eject into the transfer orbit. Usually it is the ship's current orbit, but, sometimes another orbit would be better as a source orbit. For example, consider a transfer from Earth to Mars, using the Sun as a reference. You would usually use the Sun as the source as you will be travelling mostly in the Sun's gravity far away from other bodies, but, since the ship is orbiting within the Earth's gravity, it is better to use the Earth as reference for initial calculations in this MFD mode.

When the ship is not the source, a small line will extend from the position of the body the ship is currently orbiting to indicate where the ship is in its orbit. This will help your decision when to do the ejection burn. Ejection burn is usually preformed when this line is pointing away from the Sun.

Hypothetical transfer orbit

In Orbit MFD mode, and a target is selected, it will display the source (ship's) orbit, if it's big enough to see, and the target's orbit. It can display the transfer orbit only after the burn is completed. In HTO MFD mode, this allows you to calculate an orbit based upon time of ejection, and DV added. So, by adding or subtracting, it will calculate an orbit based upon these two parameters to show you the calculated future orbit. If it does not reach the target, you can make adjustments and run it again, until the future orbit reaches the target.