View attachment 25392
The Dragon capsule has 3 attachment points in the trunk (left, right,center).
To have a payload centered, the correct attachment point (2) shall be used:
SPS:Artemis8\SPS
..
ATTACHED 0:2,Dragon
...
END
But, as shown in the screenshot, the SPS is not designed to fit inside the trunk, it is too big and upside down.
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To have a propulsion package inside the trunk, I played around with "Trunky", a tank and engine pallet in the trunk.
It would provide independent propulsion, using 2 redundant thrusters and its own fuel supply.
In case of a flight abort it would be jettisoned right away, not to hamper the escape of the Dragon.
However, as this would require launching on a man-rated FalconHeavy, I did not further follow-up this design.
View attachment 25393