Launch Window & Flyby Planner for Kerbal Space Program

Mission parameters

Basic instructions

1. Select the celestial body you will be departing from.
2. Enter the altitude of your parking orbit around that body. This is assumed to be a circular, equatorial orbit.
3. Select the celestial body you wish to travel to.
4. Enter the altitude of the orbit you wish to establish around your destination body. You may check the "No insertion burn" checkbox instead if you intend to perform a fly-by or aerobraking maneuver.
5. Enter the earliest departure date to include in the plot. Generally this should be your current game time, which you can find in the tracking station in the game.
6. Click the "Plot it!" button. After a few seconds a plot will appear showing how much Δv is required to reach your destination for different departure dates and times of flight. Click on any point on this plot to see full details of the selected transfer.

Advanced tips / Using the new tools

• After plotting a transfer use WSAD keys to move your selection.
• As you change the selected transfer the solar system view (left) will be updated to reflect your flight path and the flyby path will be drawn in the destination body view (right).
• Each of these views may be panned by click-draging with the mouse and may be zoomed in and out using the mouse wheel.
• The box immediatly under the "Delta-v transfer plot" will contain a listing of possible post-flyby encoutners which can be achieved with the selected transfer. The format of this information is "Body(orbits of craft) delta-v" as executed near/within the SOI of the flyby body. Hovering over an entry in the list will show its "Time of flight", this is the time AFTER the flyby.
• The value specified by the "Final orbit" field controls the Pe used at the flyby body (both with and without "no insertion burn" selected).

Selected transfer details

Departure

Arrival

Time of flight

Phase angle

Ejection angle

Ejection inclination

Ejection Δv

Transfer periapsis

Transfer apoapsis

Transfer inclination

Transfer angle

Plane change time

Angle to intercept

Plane change angle

Plane change Δv

Insertion inclination

Insertion Δv

Total Δv

Refine transfer

More about the solar system view

• Your inital transfer path is shown in GREEN.
• The trajectory your ship will take after the flyby is shown in BLUE.
• Mouse wheel zooms.
• Click and drag to pan.
• WSAD keys to adjust your transfer.

More about Destination Body view

• This view is drawn such that the Sun is "up", the body is moving from left to right, and you are looking down perpendicular to the orbit of the hyperbolic flyby.
• By zooming out you can see a pink ring which repesents the SOI reach of the body as well as which end is your point of entry and exit.
• By zooming into the body you will see some gray dots which are drawn on the pools of the body - this is to help you better visualize how "top down" the view is.
• Mouse wheel zooms.
• Click and drag to pan.
• Currently this tool always computes the side of flyby as being prograde - I hope to remove this limitation in the near future to better suppport gravity assist planing.
• Moons are not currently shown.