M-Drive

The M-Drive, or Maneuver Drive, a TL–9+ gravity control based technology used as the standard Maneuver Drive in Starships.

• It is also known as a Thruster Plate, and also (somewhat inaccurately) as a Reactionless Drive or Reactionless Thruster, or by other terms, due to their design and their apparent mode of operation.
• The term M-Drive refers specifically to the Thruster Plate Maneuver Drive system that reacts against the curvature of spacetime (i.e. gravity) that is in use at standard TL throughout Charted Space, and should not be confused with the generic term "Maneuver Drive" that refers to Impulse Drives and other Relativistic Drives in general.

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Please refer to the following AAB Library Data for more information:
Starship:

• Speed of Travel

• NAFAL (STL) - (Not As Fast As Light) / (Slower Than Light)
• Light Speed (c)
• FTL - (Faster Than Light) - "Superluminal"

• Astronomical Unit (AU)

» Imperial Standard Astronomical Unit

• Light-second (ls)
• Light-minute (lm)
• Light-hour (lh)
• Light-day (ld)
• Light-week (lw)
• Light-year (ly)
• Parsec (pc)

» Solomani Parsec

» Vilani Parsec ("Deshi")

» Imperial Standard Parsec

• Spacecraft Drives (Interplanetary Drives)

• Reaction Drives:

• Reaction Rockets:

• R-Drive (Rocket Drive)
• O-Drive (Orion Drive)
• P_H-Drive (HEPlaR Drive)

• Impulse Drives:

(Field Propulsion Drives / Propellantless Drives)

• Z-Drive (Lifter / <1.0 D)
• G-Drive (Gravitic Drive / <10.0 D)
• M-Drive (Maneuver Drive/Thruster / <1000.0 D)
• N-Drive (NAFAL Drive / <¹/₈ ly)

• Reactionless Drives:

• T-Drive (Reactionless Motion Thruster):

• Gyroscopic Inertial Thruster (GIT)
• Dean Space-Thruster Drive

• T_N-Drive (Reactionless Field Thruster: Advanced Gravito-Nuclear Impulse Thruster)

• Deep Space Maneuver System - ("Reactionless")

• Starship Drives (Interstellar Drives)
  • N-Drive (NAFAL Drive / < ¹/₈ ly)
  • J-Drive (Jump Drive / > 100 D)
  • Alternative FTL Drives

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Description (Specifications)

The fourth significant development came from the search for a starship maneuver drive that did not lose efficiency when away from a strong gravity well. Artificial gravity and damper technology led to yet another sub-atomic force-based technology. This new, artificially generated force pushes against a vessel's "thrust plates" themselves, which make true reactionless thrusters a reality for starship sized vessels.

The M-Drive use their own gravity field itself for propulsion, by "grabbing on" to the curvature of space and running along it much like an ant on the slope of a sugar-bowl. The M-Drive uses the stellar system itself as their reaction mass.

Unlike the ant in the earlier example, however, the slope of the bowl has a different effect on the gravitic-drive ships. They depend upon the slope for propulsion. Beyond a certain point, quantum-gravitic effects drastically reduce the efficiency of a gravitic drive ship by a factor of a hundred or more, and thus they cannot maneuver effectively in deep space.

Thruster plates work normally until the curvature of space reaches a threshold. Below that threshold, quantum-gravitic effects drastically cut the effectiveness, by a factor of a hundred or more. That cutoff level turns out to be around 1,000 Diameters (9.3 AU for the sun. Red Dwarfs can have limits as small as 1 AU, and Blue Giants can have limits as large as 30 AU). Thus Thruster plate equipped ships can't maneuver effectively in deep space. Ships intended to routinely operate out beyond the cutoff are generally designed with some form of auxiliary propulsion (Fusion Drives or HEPlaR are the most popular).

History & Background (Dossier)

The theoretical underpinnings of M-Drives involve the strength of gravitational fields from stars and worlds. The practical result is that In-System Drives operate within specific distances of stars and worlds, and are essentially unusable beyond those distances.

Power for the drives is provided by the ship's power plant. Technology level requirements for maneuver drives are imposed to cover the grav plates integral to most ship decks, and which allow high-G maneuvers while interior G-fields remain normal.

References & Contributors (Sources)

This article has metadata.

This list of sources was used by the Traveller Wiki Editorial Team and individual contributors to compose this article. Copyrighted material is used under license from Mongoose Publishing or by permission of the author. The page history lists all of the contributions.

• Marc Miller. Referee's Manual (Game Designers Workshop, 1987), 56.
• Frank Chadwick, Dave Nilsen. Fire, Fusion, & Steel (Game Designers Workshop, 1994), 72-73.
• Don Perrin. Starships (Imperium Games, 1996), 71.
• David Golden, Guy Garnett. Fire, Fusion & Steel (Imperium Games, 1997), 65.
• Marc Miller. T5 Core Rules (Far Future Enterprises, 2013), 323-327.
• Traveller Wiki Editorial Team
• Author & Contributor: Lord (Marquis) and Master of Sophontology Maksim-Smelchak of the Ministry of Science