Talk:Place-Anywhere 7 Linear RCS Port
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You can have a controllable craft using only 4 of those in vertices of regular tetrahedron. One thruster (back) points directly away from CoM and 3 (front) point away from a point slightly in front of CoM. Back thruster moves forward, 3 front thrusters combined move backward and 1-2 front thrusters plus back thruster provide rotation.