Alamo-class Frigate
Overview
Named after the Battle of Alamo, the Alamo-class Frigate was commissioned in 2161 as one of the new ship classes commissioned following the end of the First Contact War. The Alamo-class Frigate's design was based on the York-class Cruiser and was designed to be more capable than it's turian counterpart.
Frigates were a light escort and scouting vessels equipped to screen and support the larger Cruisers, Dreadnoughts and Carriers. They are outfitted with sophisticated GARDIAN defense turrets to provide anti-fighter screening for capital ships. In fleet combat, Frigates are organized into "wolf pack" flotillas of four to six ships. They use their superior speed and maneuverability to evade and maneuver into the opposing fleet to take down ships whose kinetic barriers have been destroyed.
Outside of fleet combat, Frigates make up the bulk of Flotillas. While in Fleet formation, escort Frigates intermingle with and surround capital ships, ready to respond to threats at a moment's notice. While Scout Frigates form a protective sphere around the fleet, thousands, or even 10s of thousands of kilometers wide, scanning for hostile threats before they get anywhere near the core of the fleet.
When on patrol, Flotilla disperse across entire systems, operating solo, but in constant communication with each other and their flagship at all times, while also remains close enough to reinforce each other in minutes.
Frigates were also designed for atmospheric combat and possessed dropship capabilities.
By 2186, Hastings-class Frigates made up 65% of Alliance Frigates. Less than 15% of these ships would survive the Reaper war. Those that did would eventually be decommissioned within the following decade as new ships based on reaper technology would completely outclass them.
Hull and Superstructure
The Alamo-class' hull features an aerodynamic, jet design built around it's main gun, with articulating thrusters that form part of its large triangular wings.
From stem to stern the Alamo-class Frigate has a length of 137.3 meters, a wingspan of 56.3 meters and a height of 30.2 meters. With a mass of 19,400 metric tonnes.
The main hull has a length of 103.1 meters, a width of 13.8 meters and a height of 16.7 meters.
The hull is protected by up to 320 millimeters of layered ablative ceramic composite armour plating. This armour serves as the inner layer of ship defenses. The armour is primarily designed to defend against directed energy weapons like lasers by boiling away when heated. The vaporised armour material scatters the DEW beam, rendering it ineffective.
A scaffold was built around the interior pressure hull, with sheets of ablative armor hung from the structure. Ships typically have multiple layers of armor separated by empty baffles, spaces often used for cargo storage.
The exterior hull is also lined with strips of ceramic as part of it's Defused Radiator Array, used to radiate the ship's passive heat build-up from everyday functions such as running thrusters, drives and other internal systems. Under thermographic imaging, this makes the ship appear striped, leading to the nickname "tiger stripes" or "war paint". Though, they are not as efficient as regular radiator panels, they are more durable. If damaged by enemy fire, the ship only loses a small portion of it's radiation capacity. In most cases, a vessels DRA alone allows it to cruise with no difficulty. Operations inside solar systems can cause problems.
During combat, the ship utilizes droplet heat sinks built into the hull itself. Filled with lithium, these sinks capture the titanic amounts of heat generated by weapons and thrusters during combat. Once filled to capacity, the lithium is sprayed out of nossels at the bow in the form of droplets, where they are cooled in the cold vacuum of space before being sucked back in at the stern. Droplet sinks can manage 10 to 100 times more heat than a DRA, but every time they are cycled through, a portion of the lithium coolent is lost to space. Limiting their use to only when necessary.
Shields
The Ships also feature a Frigate-grade anti-bombardment kinetic barrier array linked to a Model 5 kinetic barrier shield generator. Based on the York-class design.
Kinetic barriers consist of hundreds of tiny emitters spaced evenly across the outer hull. An object with mass traveling above a certain velocity will trigger the barrier's reflex system, generating a localised repulsive mass effect field around the point of impact, deflecting it.
This allows the ship to withstand impacts from ship-based weapons, but doesn't do anything against Directed Energy Weapons such as lasers.
The strength of the kinetic barrier depends on the size of the mass effect drive, the amount of element zero used and overall design of the drive and generator. The more powerful the mass effect fields the ship generates, the more powerful the shields can be. Alamo-class Kinetic barriers are rated for 543.92 terajoules of kinetic energy. The equivalent of 130 tonnes of kinetic energy per square centimeter. Estimated to be capable of shrugging off direct hits from a turian Frigate.
Power and Propulsion
The ship's drive core is a Mk IV Orion Mass Effect Drive Core. This massive drive spanned across all 3 decks. It's a modification of the older Mk III that incorporates turian design principles. The drive is powered by the ship's on board helium-3 nuclear fusion power plant, which delivers a powerful electrical current to a core of element zero, causing it to radiate large amounts of dark energy, which are captured by the mass effect field generators.
The Orion Drive is used to increase the power of on board weapons, generate kinetic barriers, reduce the mass of the ship, generate gravity, power inertial dampeners and more, but the most significant advantage the drive gives is the ability for faster than light space travel. The mass effect field generator generates a mass reducing field around the ship, lowering it's mass, while simultaneously raising the speed of light around it. Allowing for faster than light travel through conventional thrust without any negative effects. Ships accelerate for half the journey, befor flipping around and decelerating for the other half. This means that there is no consistent speed. A ship's FTL travel time is largely determined by the distance they travel. Longer distances allow for higher average velocities than shorter distances.
The Mk IV Orion Drive allows for a rate of approximately 69,200 km/s of acceleration and deceleration. Allowing for the ship to travel roughly 13.7 lightyears within a 24 hour period. However, due to static build-up of the drive core, the ship can not maintain FTL flight for longer than around 50 hours at a time. Limiting it's maximum FTL speed to around 59 lightyears every 2 days.
One downside however is that as the ship accelerates, the difference in light speed between the interior and exterior of the field causes a doppler shift. Objects outside the ship redshift, eventually only becoming visible to the ship's radio telescope antenna. As the ship goes faster, high-energy electromagnetic source such as x-rays, gamma rays, and eventually cosmic ray sources become visible, replacing stars with pulsars, the accretion disks of black holes, quasars and gamma ray bursts.
To an outside observer, the ship appears to be surrounded in a blue or purple aura as the light within the mass effect field is blueshifted into higher frequencies, making the field itself visible to the naked eye. The ship's radiation emissions are also compressed as a consequence. If within a field that allows light to move twice as fast, the ship produceed twice the emissions. If in a field that allowed for 200 times faster light speed, it's visible light is emitted as x-rays and gamma rays and the infrared heat of the hull is blueshifted up into the visible spectrum or higher.
As a result ship is almost completely blind during FTL flight, requiring a specially trained navigator to plot each FTL jump and instuct the helmsman on course corrections based on calculations provided by the ship's FTL plotter. If an object of significant enough mass is in the path of a planned FTL jump, a safety lock built into the drive core prevents the ship from accelerating above safe speeds. The safety lock was intentionally designed to be integral to the FTL warm-up process. Meaning that removing or tampering with the mechanism could cause critical damage to the drive core.
Ships also can not perform an FTL jump while under fire. Accelerating to FTL necessitates that a ship reduce it's mass to levels unsafe for combat. During large-scale combat, it's common practice for a losing fleet to sacrifice a portion of their forces to draw enemy fire while the rest of the fleet escapes. These ships would then attempt to escape combat at sublight speed, where they would jump to FTL as soon as they were out of range and rendezvous with the rest of the fleet.
Conventional thrust was provided by 4 aft and 2 fore antiproton drives witch inject antiprotons into a reaction chamber filled with hydrogen. The resulting matter-antimatter annihilation provides unmatched motive power. The drawback is fuel production. Antiprotons are produced one at a time in massive solar arrays orbiting energetic stars. Making them both expensive to produce and easy targets during wartime. The exhaust of an antiproton drive is measured in millions of degrees Celsius. Any ship caught behind it would melt like wax in a blowtorch.
Maneuvering is performed by an array of liquid oxygen/liquid hydrogen reaction control thrusters.
The ship features backup hydrogen-oxygen fuel cells to meet the minimum power requirements for the ship to function for a few hours, even after the fusion plant is taken offline.
Crew and Compliment
The standard crew size of an Alamo-class Frigate was 20, plus accommodations for a squad of up to 10 marines as required.
Emergency escape vehicles consist of 8 M-78 Hammer emergency evacuation pods, each equiped with their own emergency beacon, thruster module, heat shields, inertial dampeners and at least a week's rations for a crew of 8.
As standard, Alamo-classes also carried an M-35 Mako All-terrain Infantry Fighting Vehicle and an M-44 Hammerhead Light Hover Tank in the cargo hold, rated for aerial deployment. However, depending on mission, this can be swapped out for an M-080A Megalodon APC or M-080B Megalodon Missile Truck.
Sensors and Communications
An Alamo-classes features a variety of active and passive sensors that give it a detailed visual of it's surroundings.
Passive sensors are used for long-range detection and include visual, thermographic and radio detectors that monitor the ship's surroundings at all times.
Active sensors are shorter range, but more accurate. They include ladar and radar that emit a "ping" of energy and "listen" for a return signal. Radar has a wider field of view than ladar, but ladar's higher resolution allows images of detected objects to be assembled.
Due to light-lag, passive sensor accuracy is reduced and active sensors don't work while the ship is traveling at FTL speeds.
Communication is achieved through tight-beam communication, which fires a communications laser at the nearest FTL comm bouy. Acting as mini, primative mass relays, these bouys use mass effect FTL corridors to transmit the data at superluminal speed along the comm bouy network. Depending on the distance between the sender and their nearest comm bouy, this method of communication is almost instantaneous, especially since military communications take high priority when it comes to communication bandwidth.
Armament
The Alamo-class' primary armament is a single SP-90 Mk III Light Mass Accelerator Cannon mounted along the spine of the ship. Accelerating a 20 kilograms slug of ferric titanium alloy at a velocity of 453 km/s every 2 seconds. Impacting with 2.05 terajoules of kinetic energy. Equivalent to 490 tonnes of TNT. With an effective range from 600 meters to 4,200 km
Mass accelerators reduce the mass of a solid metal slug then accelerate it to high velocities using precisely controlled electromagnetic attraction and repulsion. Mass accelerators are able to achieve such high velocities that slugs had to be designed to deform on impact to increase the amount of energy transferred to the target. Otherwise it would pass right through, doing minimal damage.
As of 2182, Alamo-class Frigates included 2 M-83 Javelin torpedo tubes as a secondary short-range weapon to compliment their point-defence network. Javelin torpedo are scaled up variants of the Fighter-launched disruptor torpedo. Like Disruptor torpedos, Javelins are equipped with element zero warheads that create random, unstable mass effect fields that warp space-time around them. In flight, they use mass increasing fields making them too massive to be blocked by kinetic barriers, but also making them sluggish and easy prey for point-defence systems. Javelins are fired in large numbers and in pairs, on converging trajectories, programmed to collide, just before impact, allowing the dark energy field emitted by the impact to resonate, magnifying the resulting warp effect.
The ship's General ARea Defense Integration Anti-Spacecraft Network (GARDIAN) is used for close-in defense against enemy missiles and fighters as well as short-range anti-ship weapons used against enemy Frigates in knife-fight combat. Completely bypassing kinetic barriers and boiling away ship armour. Consisting of 16 anti-missile and anti-fighter laser turrets on the exterior hull. Since lasers move at the speed of light, they can not be dodged by anything traveling at superluminal speeds. At the start of combat, GARDIAN is 100% accurate. It's not necessarily 100% lethal, but it doesn't have to be. Damaged fighters have to break off attack for repairs. Defraction restricts GARDIAN's effective range to only a few kilometers. Fighters attack in swarms in an attempt to overwhelm the ship's GARDIAN defenses, the first few will be shot down, but as a battle progresses, overheating deteriorates both the accuracy and strength of the laser turrets.
Layout
An Alamo-class Frigate had 3 decks.
Deck 1 was the command deck and consisted of the bridge, Combat Information Centre and Communications room.
Deck 2 was the crew deck and consisted of the Crew Quarters, Captain's Cabin, Mess Hall, Medical Bay and main Battery.
Deck 3 consisted of the Cargo Hold, containing the vehicle bays and an armoury. As well as access to Main Engineering, housing the drive core and power plant.
Ships of the Line
- SSV Alamo FF-186: Active 2161 - 2186
- SSV Hong-Kong FF-664: Active 2183 - 2193
- SSV Leipzig FF-438: Active 2174 - 2186
- SSV Trafalgar FF-212: Active 2167 - 2186