Airships within the Manifold are a relatively old technology. Having been the subject of continuous research as the only known method by which people might visit adjacent tesseracts, modern dieseltech airships have developed along different lines than those found in other universes. Verdial sporeships were the first man-operable aerostats, with records of the first instance of a bundle of gas spores used to intentionally lift a person off of the ground being lost to history. In 7729, a Rostran tinkerer by the name of Vexan Zin created the first man-operable hot air balloon, allowing the altitude of an aerostat to be controlled without loosing a portion of the lifting envelope itself (as in the case of sporeships). Flight in these early times was limited in control, with weather forecasting, air current charts, sails, and even dray creatures (such as floating briars) being of limited utility in choosing the direction and speed of travel. Small steam boilers were capable of turning propellers while also metering altitude, but their extreme bulk made this an impractical solution for most applications other than exposition events. This state of affairs changed with the invention of diesel technology around 9800. While early diesel engines were bulky, subsequent integration with electric dynamos, miniaturized mechanical computers, and improved navigational equipment - all elements of the dieseltech revolution - allowed airships to move counter to prevailing air currents, use less lifting gas if used in conjunction with lifting body forms, and ascend to greater heights than ever before. Breakthroughs in chemical engineering created lifting envelopes strong enough to tolerate higher altitudes and lifting gasses which were easier to produce and handle than ever before. These innovations allowed dieseltech airships to cross an inflection layer for the first time in 9842, and the first skystations to be launched into permanent orbit in 9856. Because inflection layers and commissures both feature micro-gravity environments, special considerations must be made in terms of airship design for models intended to traverse such regions. An airship which will spend time in either environment must feature sealed cabins - or at least provide re-breather masks to crew - due to the variance in ambient air pressure. The airship must accommodate careful control of buoyancy to avoid either a sudden rise (inducing barotrauma in the crew and damage to the lifting envelope) or a sudden fall (to avoid crashes or extreme speed through conjested commissure airspace). Many airships will feature a degree of radial symmetry such that crossing from one side of an inflection layer or another will not cause a sudden reorientation, as the envelope will always rise towards the nearest region of low air pressure and the heaviest portion of the airship will always sink towards the nearest cube face. Long-haul airships with truly massive envelopes might even feature small centrifuges to prevent micro-gravity ailments (such as bone demineralization) from befalling the crew.
Dieseltech airships typically draw power from dynamos integrated into the designs of their diesel propulsion engines. Chemical batteries are a common form of backup power.
Dieseltech airships are fitted with propellers which provide useable thrust, whether integrated into nacelles on outriggers or, for airships with a degree of radial symmetry, in the hollow space formed by the tube-shaped lifting envelope. Airships of the latter design might also feature a nozzle and intake plug which are also lifting envelopes to turn the whole vessel into an oversized ducted fan assembly.
Weapons & Armament
Dieseltech airships carry a wide variety of armaments, including projectile weapons, incendiary weapons, bombs, missiles, smokescreens, and more exotic weapons based on region of origin. Due to the enclosed nature of the Manifold, dieseltech airship weaponry is typically designed to minimize collateral damage on a miss, and the limited supply of certain resources dictates that ammunition be made of relatively common or renewable materials (such as Ovinex ironwood).
Armor and defense
Because carry weight is a serious consideration when designing a dieseltech airship, armor tends to be thin and non-dense. Redundancy, especially when it comes to lifting envelopes, is a more important design consideration than outright durability. In addition to physical defenses, fire suppression equipment, radio jammers, camouflage, and speed are also incorporated into combat airships to complicate the targeting solutions of opponents.
Communication Tools & Systems
In the era of dieseltech airships, radio is the sine non qua of long distance communication. Signal pennants and flash codes (via signal spotlights) may also be employed when the sender and receiver are close together and discretion is required. Vessels might dock alongside one another or use launches to exchange messages face-to-face. Civilian dieseltech airships are typically required to employ signal lights and identifying marks when operating in occupied airspace.
Optical equipment, spherical compasses, artificial horizons, radio detectors, altimeters, barometers, thermometers, and radio communication equipment help dieseltech airships navigate and detect potential threats.
Additional & auxiliary systems
Mechanical and dieseltech computers can aid in fire control and navigation, with some expensive airships even featuring a degree of auto-pilot capability, though these still require the services of a trained Navigator's Guild navigator to operate (due to the Guild's equipment monopoly, expertise monopoly, and political clout).
Hangars & docked vessels
Particularly large dieseltech airships can carry parasite fighters or even provide refit and tender services to aircraft and other, smaller airships. Technically, skystations located in the inflection layers are a form of dieseltech airship, though their immobility typically causes people to discount them as such.
Varies based on role. Cargo airships and parasite carriers tend to be slow and bulky, but make up for their lack of speed with efficiency and altitude capability over fixed wing aircraft.
Complement / Crew
As of yet, all dieseltech airships require at least one crew member (pilot) to operate within a cube and two (including a navigator) to operate between cubes or tesseracts.
Cargo & Passengers Capacity
Varies based on role. Large amounts of cargo necessitate the employment of a loadmaster, while large numbers of passengers necessitate the employment of attendants, ticketmasters, and various other service personnel (i.e. maids).