Guide:Ptolemy

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Ptolemy fleet tug / tender
Ptolemy
Class Overview
Category fleet tug / tender
Operational 2224-2289
Constructed 31 total
  • Robinson (prototype): 1 (built 2217-2219)
  • Ptolemy: 15 (built 2222-2227)
  • Ptolemy refit: 14 (converted original 2256)
  • Keppler: 15 (built 2255-2258)
Dimensions
Length
  • 211.6 m (NX-3800)
  • 212.0 m (Ptolemy original)
  • 222.0 m (Ptolemy refit)
  • 220.1 m (Keppler)
Beam
  • 107.0 m (NX-3800)
  • 127.1 m (standard)
Height
  • 67.2 m (NX-3800)
  • 68.2 m (Ptolemy original)
  • 66.1 m (Ptolemy refit)
  • 67.0 m (Keppler)
Mass
  • 326,500 tons (NX-3800)
  • 421,000 tons (Ptolemy original)
  • 486,500 tons (Ptolemy refit)
  • 626,900 tons (Keppler)
Performance
Cruise Speed
  • w 4 (Ptolemy)
  • w 6 (Ptolemy refit, Keppler)
Tow Speed
  • w 3 (Ptolemy)
  • w 4 (Ptolemy refit, Keppler)
Max Speed
  • w 5.0 (Ptolemy)
  • w 8.0 (Ptolemy refit, Keppler)
Endurance 1 year
Complement
Officers
  • 16 (standard, most dilithium tugs)
  • 22 (with passenger or battle pod)
Enlisted
  • 68 (standard, most dilithium tugs)
  • 198 (with passenger or battle pod)



Cargo
  • 2x 121,600 tons (Ptolemy, typical cargo pod arrangement)
  • 3x 121,600 tons (Ptolemy refit, Keppler, typical cargo pod arrangement)
  • 500,000 tons (maximum load other than pod, typically 2 spare warp nacelles or mass-reduced starship)
Tactical Systems
Beam Weapons

NX-3800:

  • n/a

Ptolemy:

  • 4x laser emitters (500 MW) (single mount) (2 dorsal/2 ventral)

Ptolemy refit, Keppler except NCC-3826:

  • 2x phaser VI emitters (in 2 single banks) (aft bridge)
  • 2x phaser VI emitters (in twin bank) (fwd ventral sensors)

All:

  • Heavily armed battle pods sometimes carried


Shields
  • 1-layer conformal forcefield
  • Primary navigational deflector (support strut)
  • Secondary navigational deflector (fwd hull)
Transporters

Ptolemy:

  • 1x GP (6-pad), Mk I
  • 1x emergency evacuation (22-pad), Mk I
  • All ships brought to Mk II standard after 2241

most Keppler:

  • 1x GP (6-pad), Mk III
  • 1x emergency evacuation (22-pad), Mk III

NCC-3816-3820:

  • 1x GP (6-pad), Mk III
  • 1x cargo, Mk III
  • 1x emergency evacuation (22-pad), Mk III
Auxiliary Craft

Original:

  • 2x shuttlepods
  • 1s work pod

refit 2241, Keppler:

  • 1x work pod
Historical
Ships of Note
  • USS Aristarchus (NCC-3805)
  • USS Keppler (NCC-3816)
  • USS Kidinnu (NCC-3826)
  • USS Ptolemy (NCC-3801)
  • USS Robinson (NX-3800)
Canonicity
Design STII, Franz Joseph (Keppler: aridas sofia)
Name FJ
History FJ



In the early 2220s, as the threat from Klingons kept escalating, it was found that there were no resources for building starbases at the rate required to support operations on the faraway Klingon border. Furthermore, the torpedoes now in use aboard virtually all modern spaceships were useless without antimatter for their warp engines or warheads, and the starbases specifically equipped to produce this commodity in the 2190s were few and far between. To safely carry the volatile energy source to remote ships and bases, a new type of tender ship would have to be launched, more independent in operation than the earlier ships of this function. Simultaneously, the ever-increasing size of Starfleet frontline starships meant that a Fleet deep space tug of unforeseen dimensions would soon be needed for most recovery tasks. Starfleet decided to tackle the problems at the same time, equipping its heavy tug with tender and tanker gear and with the weapons and shields needed to survive in deepest space.

Geering Space Structures had already secured the contract in 2217, back when the project schedule had been more forgiving. Yet the prototype USS Robinson (NCC-3800), built around a 107 m saucer and structurally completed in 2219, suffered from systems integration problems and was nowhere near operational testing status when the needs of the frontier became acute. The repeated successes of the Chiokis Corporation prompted Starfleet to move the tender project over to that company in 2222. It was an excellent opportunity to test the company’s new 127.1 m saucer hulls, which would be compatible (and competitive) with all the starship contracts currently in Geering hands.

The bottleneck technology was the constructing of power plants and warp engines. Thus a ship compatible with many existing thermonuclear power plants was built, and storage provided for antideuterium, deuterium and tritium fuel alike. Save for the prototype which had utilized the proven PB-18 design due to a Geering decision to avoid unnecessary development risks, the standard propulsion arrangement for the tug/tender became a pair of PB-29 warp nacelles. The two-lobed field could be extended around a ship or pod in tow, up to the size of the latest Mann and Baton Rouge class cruisers. The requirement was later modified to include the planned Chiokis series heavy cruisers as well.

A combined tractor beam assembly and antimatter replenishment boom extruded from between the downward-tilted engine pylons. Docking the tender upside down against the engineering hull of the various ship designs enabled transfer of fusion fuel, antimatter, supplies and crew directly to the waiting vessel. After 2241, ACB modulation in Mk II transporter systems made transport of antimatter fuel theoretically possible. The need for a hard-docking system continued, though, since antimatter remained difficult to transport in large quantities.

Various cargo modules, most of them based on the classic Type VII cylinder, could also be towed when attached to the docking boom. This gave the class a secondary role as a general transport/cargo tug – although most cargo pods ended up being towed by more conventionally sized cargo tugs instead of the huge Starfleet tenders. A special passenger pod was a sublight spaceship unto itself, and necessitated extra crew to run, even in attached flight mode. Also, torpedo armament was incorporated into an inconspicuous-looking pod that was intended to give a nasty surprise to pirates or Klingon raiders.

File:The space train by puffinstudios-d8wbz7f.jpg
Moving heavy civilian cargo pods like this liquid gas carrier of Dytallix Mining Corporation was one of the many missions of the Ptolemy class. Most of the time, these ships carried Starfleet pods or served as fleet replenishment ships. However, a priority was always given to heavy starship towing missions, of which no other class was capable. The more modern Doppler and Dollond variants shared the mission profile of the Ptolemies, although their greater numbers made possible a more extensive cargo-carrying role.

The tug/tender design was named Ptolemy class after the first completed Chiokis product, and in keeping with the originally-chosen convention of famous Earth astronomer names. Beginning in 2224, fifteen hulls were built and at first given either minimal laser armament with two single banks above and below the saucer, or no armament at all. Nevertheless, there existed potential for equipping the imposingly large vessels as frontier warships – not mere auxiliary combatants, but true warfighters comparable to light cruisers. From the mechanical-computational point of view, the weapons berths could easily accommodate phasers as those became available. These new weapons could not be used without the installation of a new secondary plasma system, however, and such a refit had to wait for an overall power system modernization. In 2255, dilithium power was finally introduced to the tug fleet, as fifteen new Ptolemy ships (also known as the Keppler subclass) were built complete with PB-48 warp engines and modern saucer contours. The PB-48 was one of the first practical applications of the new ‘linear’ solid state warp coil technology, although the practicability soon was challenged by a poor reliability record.

Modern cruiser-standard PB-32 engines, made affordable by Starfleet budgetary expansion and vital by Federation spatial expansion, were in turn provided for fourteen of the first-generation Ptolemies. This gave them, too, a top speed of warp 8. Warp 4 could be achieved when towing another vessel. Also, these new solid-state coil assemblies enabled the extending of the warp field over far larger vessels or a combination of two or even three cargo pods. This mixture of cruiser-like and decidedly uncruiser-like characteristics was mainly a side product of a decision based on the affordability of an engine common with the cruiser fleet. In the long term, greater reliability proved to be the most significant advantage.

Twenty-eight of the tugs out of the antimatter-powered total received phaser armament and served as frontline replenishment and recovery ships, with the frontier operating theater dictating an occasional command, coordination or combat mission as well. One Keppler, USS Kidinnu (NCC-3826), received stock laser armament instead. Although the unarmed Robinson initially was retained by Geering as a testbed, she was later leased to Starfleet for general logistics and training use.

Some time after the Ptolemy design had been proven and antimatter technology perfected, Starfleet approved the construction of a large number of more deliberately mercantile transports based on the design. The Doppler and Dollond classes of cargo tugs were to be built with limited weaponry and without military sensors, and to feature modern and economic linear warp engines. This was expected to result in significantly lower construction costs and enable large numbers of the ships to be built, to form the mainstay not only of Fleet heavy replenishment, but of its heavy cargo services as well. The first such ships were scheduled to enter service in 2268 with LN-23 early linear warp engines, but development of the engine type soon met with severe problems. As an interim measure, the Kepplers were in 2271-72 fitted with LN-52 engines instead.

Only in the 2290s were the Dopplers and Dollonds finally fielded, complete with LN-41 and LN-64F series advanced warp engines and several improved features. They are later described in an entry of their own.

Worth mentioning is the fact that the pennant codes of cargo pods carried by these vessels are supposed to feature the letter C before the actual registry number. Thus, NCC-C2000 is not an Excelsior class heavy cruiser but a dry bulk cargo container! A glitch in a Starfleet logistics management program erased the letters from the self-organizing central registry records in 2241. Recovery would have required a system-wide booting that would have brought the entire Federation to a grinding halt; potential losses from the procedure were estimated at six trillion credits and 5,000 fatalities – or millions of people lost, were the registry to be damaged, or triggered to take self-preservative action. This persisting error has caused no small amount of anguish among traffic controllers and cargo operators. The fact that the error can’t be eradicated is one of the monuments of the fundamental inflexibility of a modern computer-run society (not to mention a Holy Grail of sorts for programmers who in the past century have come up with thousands of ideas, ranging from fantastic to absurd, on how to recover ‘The Cees’ without killing anybody).

Thousands of the standard containers were built, featuring for example Liquid, Dry Bulk, Refrigerated Goods, Products, Starliner, Troop Transport and Large Components units, as well as small numbers of towable factories, hospitals and repair stations. Even though the Ptolemy-derived tugs have long since been retired, and Starfleet now follows the commercial practice of using pods specific to ship types, many of the old containers still serve on as space stations, asteroid-mining habitats, or even in-system sublight passenger and cargo haulers.

Notes

  • Construction period brought forward to 2222 in the sidebar, per the text.

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