|This article, Hektor-Class Stealth Cruiser, is currently under active construction.|
Introduced after the war, ONI decided that its fleet of Prowlers, while suited for most of their needs, were insufficient for fulfilling a number of crucial roles that they envisaged stealth ships excelling at. In particular, they required a class of stealth ship able to launch special warfare teams covertly, in or out of slipspace, and then support ground and space operations by providing precise intelligence and waging electronic warfare against enemy ships. For this purpose, they commissioned the Hektor-Class Stealth Cruiser - with the first of the class launched in 2553, they were the first to enter service after the UNSC Point of No Return
Prior to 2549, the largest inhibitor for the Office of Naval Intelligence's fleet of stealth ships was size. While older metamaterials were advanced enough to keep a corvette-sized ship hidden from sight efficiently, larger ships had difficulty retaining those same characteristics. The sheer mass and surface area created difficulties in heat distribution and radiation, eventually allowing enemy sensors to penetrate the stealth measures and detect the ship with thermal scanners. Worse, long before the point of detection, the temperature would rise to unbearable levels. The only successful stealth ship of sufficient size, the Point of No Return, was one of a kind indeed, requiring extensive technical maintenance and even then only through the use of advanced prototype metamaterials still in testing.
The advent of the Tarnhelm metamaterial changed all that. Far more advanced than anything the UNSC had previously adopted, the Tarnhelm was able to be produced in much greater quantities, and enabled ships as large as a Marathon-Class Cruiser stealth capabilities. The only limiting factor was the UNSC's devastated production centres, which hindered its entry into service. After the war, this problem was further compounded by the loss of Reach, and the destruction wreaked upon Mars and Earth. Nevertheless, production craft finally entered service in 2553 making use of the Tarnhelm.
While the Hektor-Class Stealth Cruisers weren't the first Tarnhelm-users to see combat, they were arguably the largest. Slightly larger than a UNSC frigate, their presence on the battlefield was a closely guarded secret, even among the UNSC's own forces, requiring GAMMA THREE clearance or higher. They had been designed before the end of the war, and construction had already begun at the Reyes-McLees Martian Shipyards - their survival was a narrow thing, but they were put to great use after the war in intelligence and reconnaissance missions, mapping out enemy territory and providing starside data on potential ground campaigns. At least one was present at Unmoving Virtue, dropping ODST and Spartan insertion teams to support the ground campaign and engaging in electronic warfare operations against the Covenant ships trying to manoeuvre out of the shipyards. Others may have been present at Ketesh and Cloistering Expectancy, though confirmation is difficult given the efficiency of their stealth measures. Eventually, most of the Hektor's were retired from service in favour of the smaller, cheaper and more advanced Kusanagi-Class Stealth Frigates, though a number were refitted to serve as ONI mobile command centres.
It is often said by aerospace engineers that stealth is impossible, and for the most part this is true. Thrusters produce exhaust trails, ships give off heat signatures, and optical detection for the most part is relatively simple. Previous stealth Prowlers managed to offset some of these factors, but the potential for detection, however slim, always remained. The single advantage that the UNSC has possessed is the Covenant's poor understanding of their own sensor systems, and even their combat doctrine, allowing Prowlers to remain hidden for short periods during which they can accomplish their missions. The Tarnhelm is the first metamaterial to produce near-true stealth, allowing vastly improved capabilities to Prowlers, and the construction of the Hektor-class.
Work on the Hektor-class began long before the Tarnhelm was even revealed to the public, perhaps explaining its unconventional shape. With lesser metamaterials, designers were forced to optimise as much of the ships design as possible for stealth enhancement - the oddly angular hull refracts, reflects and absorbs RADAR and MASER, but uniquely the Tarnhelm is able to also avoid LDAR with its negative refractive index. With the strict emphasis on avoiding detection, there are many tradeoffs that needed to be made - unlike most of the newer serving ships, they lack any form of shielding, either the MJLNR-7X or the CEMPF-7, which both produce detectable radiation that would compromise the stealth capabilities. To compensate, the hull is composed of ceramic-titanium composite, and internally reinforced by a network of bracings, improving its survivability. These bracings also protect the heat sinks, where excess heat is stored in massive water tanks to prevent it escaping into space. Even its deployment systems are stealthed - SOEIV launch tubes are shrouded in metamaterial, and the pods themselves, while older, were designed to avoid detection during reentry. Launch doctrine typically holds that pods are to be launched away from the ship, correcting their course later, to prevent discovery.
For propulsion, the Hektors are also at a disadvantage. Even basic thrust-vectoring systems produce heat and radiation, and while stealth measures are engaged the ship remains extremely vulnerable. Small repulsor thrusters, reverse-engineered from Covenant ships, are able to keep the craft stable, but are difficult to run and, while certainly less detectable, produce small spatial distortions in their wake, a hazard when moving in close proximity to other objects. Their aft hall effect thrusters are also shrouded in metamaterial, hiding the point of origin for the exhaust trail, but otherwise leave the ship vulnerable to advanced tracking systems.
Significantly larger than Prowlers, the Hektor-class have a larger internal capacity, supporting a secondary Combat Information Centre for battle coordination, and is able to carry up to a platoon for security and combat deployment. For more conventional deployment and transport, the Hektors carry three D77H-TCI Pelican Dropships in a single ventral hangar. For the most part, these dropships are conventional, without any stealth measures or even armament. The UNSC Achilles carried a prototype XD77J Stealth Pelican, but little came of that. Docking collars on the starboard and port sides allow drydock compatability with most UNSC space stations and most of the smaller warships. The Achilles also carried a magnetic clamp and hull breach cutter on the ventral hull, enabling it to lock itself to an enemy ship, cut a hole in its hull, and insert a capture/salvage team to claim the ship. This feature would be used to great effect at Unmoving Virtue, where a UNSC Hektor-class inserted a Sangheili capture team into the Brute Assault Carrier Heretic Killer.
Ships of The Line
- UNSC Adrastus (CLC-77)
- UNSC Agapenor (CLC-78)
- UNSC (CLC-79)
- UNSC Polydamas (CLC-80)
- UNSC Hektor (CLC-81)
- UNSC Antenor (CLC-82)
- UNSC Andromache (CLC-83)
- UNSC Agenor (CLC-84)
- "If they were so important, why did the Navy only build eight of them? I mean, it seems counter-productive is all."
- "I remember hearing rumours about a stealth cruiser used by ONI. now we have eight of them? Man, our intelligence department must be biting off a huge chunk of the defence budget."
- "They're very angular, aren't they? I always preferred the sleek look of the older Prowlers, but if it works, it works."
- "Tarnhelm Metamaterial is used on pretty much all stealth stuff these days - aircraft, space fighters, missiles, ships, you name it. But I'd say these would have to be the biggest to use them."