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Setup a 24-hour Transfer Flight to the Moon

Open the scenario, 1. LOX-Augmented Nuclear Thermal Rocket (LANTR).scn from the TTM24 addon.

Undock the LANTR from the Earth Depot and move a safe distance away in free orbit. Switch to the PTM. Undock the PTM from the Earth Station and rendezvous with the nearby LANTR. Activate the rear docking port (shift-keypad 2) and dock the PTM to the LANTR. Once joined, setup a 24-hour transfer and proceed to the Moon.

The 24-hour Transfer

Bring up the Surface MFD and the Map MFD with the Moon as target. The Map MFD will show you the position of both your vessel and the moon in their current orbit around the earth. To reach the moon wait until the moon ( yellow + ) is 133 degrees to the right of your vessel. You may read the position of the moon in the Map MFD in degrees and the position of your ship in the Surface MFD. When the difference between the two is 133 degrees orient your ship prograde and begin to burn. You may wait to align planes with the moon after this burn or do it before if the opportunity arises. Bring up the Orbit MFD so you can watch the telemetry. Burn until the Eccentricity ( Ecc ) is 1.3000. I usually ease off my thrust near the end of the burn to get the best numbers. But the numbers are not as critical with this burn, as long as you have over 1.3000 eccentricity you will get the velocity needed to reach the moon on time. This will place your ApD way out past the moon at a higher velocity then a normal transfer would. This will allow you to reach the moon in the 24 hour time frame. This burn should use up 40-45% of your fuel.

Now you may align planes if you haven't already done so.

If things go well this will place you at the moon in lest then a day and in front of the moons orbit. In other words you will be coming out from the Earth from one side ( counter-clockwise orbit ) and enter the opposite side of the Moon ( clockwise ). What I mean to say is that you should cross in front of the moon. This is vital if you want to find yourself orbiting in the same direction as the Lunar Depot.

There are some reasons why things may not go well. The burn time calculations change for different times of the month/year and altitude of the vessel. So without the TransferMFD doing the calculations for us we may need to do a mid course adjustment. The good news though is that mid course adjustments are easy to do and they will safely nail the moon every time.

Set up the OrbitMFD to reference the moon, [Shift] + [R]. Now you can read the Rad watching your distance from the moon as you close in on it. Also be sure the moon is the reference in the HUD, [Ctrl] + [R]. Wait until you are within 100M from the moon and see where the prograde indicator is aimed relative to the moon. If your ship is heading to far to one side or the other you can turn 90 degrees to the opposite side and burn. You can use the Surface HUD to help aim you ship. If you are heading to the wrong side continue the burn until the indicator passes to the other side to place you in a clockwise orbit. This way your ship will pass in front of the moon as stated earlier. Of course you won't be able to watch the prograde indicator because you will be turned away from it. However you can watch the path in the OrbitMFD with the moon as reference. At this time you can adjust the PeD to match the target PeD of the Lunar Depot.

On the way in you can even align planes with Lunar Depot, you don't have to wait until you are in orbit. Then fly on in until you reach periapsis. At periapsis maneuver retrograde and burn until you have a ApD that will help you sync to Lunar Depot. You should be able to align planes with the Depot using very little fuel. It's a great feeling approaching Lunar Depot after a days journey. You are now ready to separated the PTM from the LANTR and dock to the Lander.

Related Links

Apollo Lunar Landing Mission Tutorial
How to Dock the PTM to the Lunar Lander


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