Monitor (naval concept)

This article is about the spacecraft design concept. For other uses, see Monitor (disambiguation).


In the context of BattleTech spacecraft, the term Monitor, although not clearly defined, is usually used to describe the concept of a WarShip without a jump drive core.

This drive core has no tactical value in combat but typically makes up 47.5% of a given WarShip's mass. The idea behind the Monitor concept is to free up this mass for weapons, armor, and other combat-relevant systems by forgoing the jump drive. Such Monitors would theoretically be vastly more powerful on a ton-per-ton basis compared to regular WarShips of the same mass.

No official rules[edit]

No official rules exist for Monitors. The very concept breaks the aerospace construction rules, as WarShips (with their size limit of 2,500,000 tons) mount a jump drive by definition. Under Canon rules, non-jump capable vessels must be built either as DropShips (size limit of 100,000 tons) or even small craft (size limit of 200 tons). Space stations are immobile structures and cannot mount tactical maneuvering thrusters, giving them limited tactical value.

Gerald Hall pioneered the Monitor concept in the MechForce magazine MechQuarterly (vol. 4, issue 2), an official but non-canon BattleTech publication. His suggested construction rules for Monitors were incorporated into the official BattleTech design program, HeavyMetal Aero, but are not canonical and violate legal construction rules.


BattleTech Line Developer Herbert A. Beas II has repeatedly[1] stated that Monitors, if they existed, would outperform WarShips to the point where they would threaten game balance, and that Monitors were therefore kept out of BattleTech for game balancing reasons. To put the issue to rest, he solicited an entry for Monitors in Experimental Technical Readout: Boondoggles to showcase that, and why, the concept was not viable in the BattleTech universe. However, within days of publication fans pointed out on the BattleTech Forum that the entry as written, which described a small number of Monitors to have been built and deployed before the project was scrapped, actually proved the Monitor concept to be viable to a degree. In response to this, an erratum was published that completely replaces the initial entry in what technically constitutes a retcon (in the sense of altering canon).

The following is a direct transcript of the official erratum posting, reproduced here verbatim with kind permission of the author, Herbert Beas:


The following errata applies to the entry titled "Monitors". Please replace ALL TEXT under this entry with the following:

Outcome Summation: Canceled Prototype
Producer/Site: Blue Nose Clipperships of Mars, Sol
Supervising Technician: Commodore Mortimer Basquiz
Project Start Date: 2683
Failure Analysis: Inefficient Design and Inadequate Infrastructure
With the advent of the compact KF drive, space became a much more dangerous place. No longer were warships limited to assault DropShips, but they could easily surpass a million tons. Yet, almost half of that mass was still tied up in the KF drive. During the latter part of the twenty-seventh century, a group of SLDF admirals pushed to create a new breed of WarShip, dispensing with the KF drive with the goal of doubling the potential firepower such a vessel could bring to bear. After over a decade of campaigning, funding was finally allocated for project AMHITRITE and Blue Nose Clipperships won the bidding to provide construction for the prototype.
Though the concept “monitor” was based on the proven hull of the venerable Avatar class cruiser, almost immediately problems emerged when the KF drive was removed from the equation. Without the frame around the KF drive acting as the ship’s primary keel, stress analysis revealed that a great deal of additional structural reinforcement would be needed to avoid integrity failure under combat thrust. The design plans were hastily re-drawn and construction resumed, but the structure reinforcements ate away far more mass than originally expected.
As construction continued on three prototype hulls, the numerous setbacks and additional costs mounted, drawing greater scrutiny from a number of oversight committees. While these monitors had a potential military impact, the potential political impact of their possible failure was orders of magnitudes greater. Internal divisions, even among the Star League admiralty, quickly formed, with pro-monitor and anti-monitor camps ignoring any data that failed to agree with their positions.
Combat simulations and technical projections won the first victories in favor of the monitors, with most simulations showing overwhelming victories between the heavily armed monitors against larger jump-capable opponents. Unfortunately, these tactical advantages paled in comparison with the logistical studies ordered by Admiral Arthur Ubuntu, who led the challenge against AMHITRITE as the construction effort stretched past eight years without a single prototype emerging from its slip.
Ubuntu’s studies quickly revealed that, in addition to the greater manpower needs each monitor would need by dint of their extra firepower alone, the support apparatus needed for widespread deployment of monitors would quickly outstrip the Hegemony’s naval resources. This monumental problem primarily stemmed from the monitors’ inability to perform their own jumps. Unbuntu noted that the monitors’ sheer mass—well beyond the scale of the largest DropShips of the day—would force the SLDF to use YardShips to transport and deploy each monitor fleet to its duty station, an expensive proposition as any sizable monitor presence in any given system would thus require dozens—perhaps even hundreds—of such jumps, even for the systems nearest to Terra. Counter-proposals to ship monitors in pieces via specialized DropShips for on-site assembly proved equally untenable, as this would still effectively require the YardShips to do the assembly work in any system that lacked shipyards large enough to do the work locally.
To make matters worse, after disputing computer simulations that underscored the physical dangers of moving monitors in this fashion, Commodore Basquiz, as head of the project, insisted on a “live test”, in which one of the half-completed prototypes would be moved from Mars to New Earth via the SLS J. Swift, a Newgrange-class YardShip. After tugboats were needed to get the prototype from its shipyard in Martian orbit to the Swift, the YardShip was damaged during the mooring process and suffered severe structural and drive damage after the jump to New Earth. The damage was so severe that a second YardShip was needed to take the monitor back to Mars, while the J. Swift needed five months of repairs before she could jump again.
Convinced of the inability to properly produce, deploy, and maintain a suitable fleet of monitors for local system defense even in the Sol system, the Star League scrapped the monitor project, and ordered the incomplete hulls dismantled. Not a single one of the prototypes ever flew under its own power.

We apologize for the inconvenience.

Thank you,

- Herbert Beas

Existing Monitors[edit]

Although the Monitor concept at large was refuted, a few isolated cases exist in canon that could be regarded as Monitors:

  • The Bonaventure-class corvette Sheridan, as of 3067, operates as a training ship in the Sol system. It has had its jump drive removed to make room for a full second crew compliment and some training gear; however, it is unknown just how much of the jump drive was removed and how much room/mass the extra facilities take up.[2]
  • The Word of Blake's converted Naga-class SDS control ships in the Sol system were effectively monitors.[3]
  • Battlesat type space stations with (limited) thrust power could also arguably be described as monitors. It should be noted that they are legal under current construction rules, but have been rendered largely moot due to their limited movement. As a consequence, it is questionable if battlesats were deployed outside of the known canonical example in the Luthien system.[4]
  • Despite its name, the Cockatrice Monitor Platform is technically a DropShip (its design in turn based on a Small Craft, the K-1 DropShuttle); while it could be described as a monitor in a functionality sense, it is not a Monitor in the design sense of being a WarShip without a jump drive core.