JumpShip

Description

In the BattleTech universe, JumpShips are the pivotal element of interstellar travel. They facilitate faster-than-light (FTL) movement - "Jumping" from one Jump Point to another, typically in a different star system, covering up to 30 light years in mere seconds. Docking Hardpoints allow JumpShips to carry DropShips along for the Jump, effectively serving as a Jump tug.

Jumping with their load of DropShips is about the only task that JumpShips are designed to perform. It is the DropShips that handle all movement of goods and passengers within a star system (including to and from Jump Points), while the large and fragile JumpShip remains at the Jump Point and only move to "jump".

Although the term JumpShip technically describes any spaceship that can "jump", it is generally applied only to civilian JumpShips, as opposed to designated military JumpShips (which are usually referred to as WarShips instead). This article adresses the former, vastly more common type; the differences of WarShips are covered in their own article.

Design

Designed exclusively to provide FTL jump capacity, JumpShips are essentially comprised of only the elemental components required for "jumping": The delicate Kearny-Fuchida Drive (K-F drive), which alone accounts for around 95% of the ship's mass and dictates the typical needle-like appearance of their fuselage, and the trademark Jump Sail to safely recharge their drive with solar energy. K-F drives cannot be smaller than 2500 tons. The theoretical maximum size for JumpShips is 500,000 tons (civilian) or 2,500,000 tons (WarShips). Most, but not all, have Hardpoints with Kearny-Fuchida Field Conducting (KFFC) Booms that extend the jump field to include docked DropShips. JumpShips are not meant to move away from Jump Points and do not have transit drives like DropShips, only weak maneuvering thrusters to adjust their position. Other than that, they only provide crew quarters and a bridge, and sometimes feature a Grav Deck, hydroponic gardens, modest cargo capacity and/or hangars for Small Craft.

Common JumpShips carry insignificant weaponry at best or are entirely unarmed, and are considered non-combatants. However, the distinction is somewhat blurred in some cases, as some JumpShips do have some level of armour and armament, some have command and communication facilities suited for coordinating large military operations, and some even serve as starfighter baseships. The key difference between civilian JumpShips and WarShips is held to be their K-F drive: All ships with a regular K-F drive are considered (civilian) JumpShips, whereas all ships with a compact K-F drive are automatically considered WarShips.

Operations

JumpShip operations are naturally limited, owing to the narrow performance profile of the ships. They do little more than jump. Between jumps they charge their jump drive and wait for DropShips to arrive and dock.

Jump preparation

In order to safely "jump", a JumpShip must operate free from gravitational influences (i.e. be located at a Jump Point), must have charged its drive coil, and any DropShips must be docked and secured properly with functional KFFC booms. Only if these prerequisites are met the ship's navigator can begin with the immediate jump preparation, namely programming the drive with the required jump data (which may take anywhere from ten minutes to twelve hours depending on the circumstances). For safety reasons the JumpShip should also have furled its Jump Sail and confirmed that no other craft are within two kilometers. When the jump program is initiated, it becomes impossible to abort the jump process.

Jump

Within a few minutes after firing up the K-F drive, warning klaxons announce the impending jump and ten seconds later the K-F field expands around the ship. It slices through anything that is not fully encompassed, and the jump takes the momentum out of everything pulled through hyperspace. If the Jump Sail was not furled prior to the jump then it will invariably be wrecked; it is possible, however, to perform an emergency jump even while the Jump Sail is still deployed. The jump also causes severe tidal stresses that may cause damage up to two kilometers away.

Damaged components of the Kearny-Fuchida may cause the jump attempt to fail, either because a K-F field fails to form or because it fails to push the ship through hyperspace, effectively "jumping" it to its current position.

Even if the Jump does not fail, a misjump can occur because of miscalculations, technical problems or spatial anomalies. Technical problems are the most common cause for a misjump, and typically results from poor maintenance or charging the jump drive too quickly. Spatial anomalies are far rarer, but are suspected to have caused the loss of several JumpShips over the several hundred years of their use. Inherent mechanics ensure that JumpShips can never jump into the gravity well of a star or planet, even in a misjump, but they can deviate from their intended target and emerge off course (i.e. up to twice as far away from the sun of the target system as intended), or even be stranded in deep space or another star system.

Passengers suffer mild dizziness from jumping. Some even suffer serious nausea for some time after a jump, in a fashion similar to sea-sickness.

Emergence

When materializing at their destination point (whether or not it was the intended target of the jump), the JumpShip causes similar tidal stresses and also advertises its presence with an electromagnetic pulse that can be detected billions of kilometers away, and an infra-red signature that can be detected from a relatively close range of up to 50,000km. Together these are called the Emergence signature, and are determined by the total mass of the JumpShip and all attached DropShips.

Drive recharging

After a jump, the K-F drive must be recharged, which is a slow and delicate process. The most common way is for the JumpShip to turn its nose towards the sun and deploy its Jump Sail, essentially a huge solar collector resembling a parachute several square kilometers in size. Station keeping thrusters allow the ship to maintain its position and counter the drift induced from solar wind. In this way, the jump drive can be recharged in six to nine days depending on the spectral class of the star. An alternative to the Jump Sail is to recharge the drive with the ship's power plant, but the delicate machinery of the K-F drive does not tolerate such treatment well.

Jump Points sometimes feature Recharging Stations. They can transfer power to a JumpShip if it is docked, or by beaming it at the Jump Sail of the ship for collection. This process still requires 150 hours to fully charge the drive.

Some JumpShips are equipped with a Lithium-Fusion Battery that provides a second charge for the K-F drive. The battery can be charged in the same way as the drive itself.

After recharging, the JumpShip is ready to jump again.

Manufacturing

The most common and best known JumpShip types are the Invader and the slightly less common Merchant. The Monolith has the best DropShip capacity (9) of all civilian JumpShips and also of most WarShips; only the huge Potemkin class troop cruiser can carry more DropShips (an unmatched 25).

Known JumpShip classes include (sorted alphabetically and excluding WarShips):

• Chimeisho - 245,000 tons, 2 Hardpoints, introduced in 3056. New design built in the Draconis Combine after reconstruction of the Izumi shipyards at Altair.
• Comitatus - 250,000 tons, 1 Hardpoint, introduced in 2995. Doubles as Aerospace Fighter carrier, carrying 25 fighters. Originally conceived by Clan Snow Raven as transport with 4 Hardpoints. In use by Clans only.
• Hunter - 95,000 tons, 1 Hardpoint, introduced in 2832. Developed by Clan Ghost Bear as a dedicated scout. Small emergence signature. Equipped with a HPG. In use by Clans only.
• Invader - 152,000 tons, 3 Hardpoints, introduced in 2631. Most common of all JumpShip classes, accounts for over 45% of all registered JumpShips. Sophisticated communications equipment.
• Leviathan - Large JumpShip type from Star League era, specifications unknown. Likened to the Odyssey and Monolith classes; smaller than Monolith.
• Magellan - 175,000 tons, 1 Hardpoint, introduced in 2960. Designed and exclusively used by ComStar for their Explorer Corps. Equipped with a HPG.
• Merchant - 120,000 tons, 2 Hardpoints, introduced in 2503. Common class in widespread use, second only to the Invader.
• Monolith - 380,000 tons, 9 Hardpoints, introduced in 2776. Rare. Often used as flagship because of superb command center facilities. Largest civilian JumpShip class ever built.
• Odyssey - 345,000 tons, 4 Hardpoints, introduced in 2887. In use by Clans only.
• Scout - 79,000 tons, 1 Hardpoint, introduced in 2712. Smallest JumpShip class in common use. Designed for exploration. Small emergence signature makes it well suited for stealthy operations.
• Star Lord - 274,000 tons, 6 Hardpoints, introduced in 2590. Docking collars are equipped with grapples that can reel in small DropShips, useful for rescue operations.
• Tramp - 250,000 tons, 3 Hardpoints, introduced in 2754. Rare class, superseded by the more popular Star Lord. Clan Nova Cat has refitted some of theirs with a 4th Hardpoint.

(See also: Category: JumpShips)