D80-X Rhea Dropship

Though the XAD82 Petrel gunship was an indisputable failure, it did provide much-needed data for another craft developed by Project EXCALIBUR. Designed along radically different lines, the D80-X Rhea Dropship is designed primarily for airlifting heavy equipment and providing Close Air Support for ground forces. Smaller than the D77 Pelican series, the Rhea has very little internal capacity for infantry, able to carry at most a squad - instead, it is designed to quickly airlift and deploy larger vehicles magnetically clamped to the ventral hull into combat zones, vastly improving UNSC armour mobility. First deployed in 2551 at Minorca, the Rhea only saw action during the Minorca and Earth theatres of combat during the Human-Covenant War, but would be extensively used during the reconstruction period, especially during joint UNSC-Sangheili operations.

History
While the Pelican has served the UNSC admirably throughout its service life, it was primarily designed for carrying infantry and supporting them only in a limited capacity. Despite many updates and refits, this still remains true - Pelican variants are usually designed to promote their ability to support infantry, and little else. In the conflict against the Covenant, the importance of armoured support has taken on much more importance, especially against Covenant energy shield technology, and provisions needed to be put in place to ensure that the UNSC could keep up with the rapid pace of the Covenant. An interim solution was the adoption of the Scorpion MBT - relatively small and lightweight, compared to other Main Battle Tanks, it was Pelican-compatible and thus easily transportable, a significant advantage against the Covenant.

A more permanent solution was sought, and provided by Project EXCALIBUR, in the form the Rhea dropship. Designed almost exclusively for transport of heavy vehicles, the Rhea was submitted by Sierra Space Systems in 2546. Designed to be compatible with virtually any UNSC heavy vehicle, the Rhea was smaller and lighter than the Pelican with a dramatically reduced passenger bay, but improved thrusters allowing it to airlift the heaviest armoured vehicles, but also includes a chin-mounted 50mm autocannon and retractable dorsal missile/rocket pods for additional CAS. The initial prototype, the D80-X1, was field tested in war games between the 427th and 88th Marine Regiments, proving to be nimble and effective in its role, towing tanks, APC's and artillery into position as needed, far better than the Pelicans it competed against. The design was approved by CENTCOM in 2549, and production on the Rhea was begun in earnest. The first production units to come out of the Sierra assembly factories were approriated by ONI to participate in Operation HOT GATES, attached to various Army, Air Force, Navy and Marine units in the UNSC's presence on Minorca. Proving to be as effective and versatile as their Pelican counterparts,the Rhea's gained a formidable reputation in combat, with soldiers and Marines nicknaming it the "Terror Bird." The most famous unit, the 3374th Marine Air Group, adopted the Phorusracos as their official emblem, symbolising their respect for the craft. At Minorca, the Rhea demonstrated many of its design strengths - its agility, speed, hauling power and flexibility. The only drawback was its smaller internal troop capacity, but this was a minor consideration in its specialised role.

After the UNSCDF was recalled for the defence of Earth, the rest of the Rhea's participated in the numerous battles for Earth, especially in and around East Africa. Hauling in artillery and heavy armour support, they allowed the UNSC to move up their heaviest equipment far more rapidly, improving their mobility against the Covenant defenders. After the conclusion of the Human-Covenant War and the Human-Sangheili Armistace Accords, the Rhea once again entered production alongside the Pelican, filling out the much-depleted UNSC aerial forces, and would play crucial roles in future conflicts..

Design
Relatively conventional for a UNSC dropship, the Rhea is slightly smaller than the Pelican, though it incorporates many of the same technologies - Ceramic-Titanium Composite hull plate pioneered by the D77F, the rotating adjustable VTOL jet thrusters, and a powerful magnetic clamp. The Rhea also includes chemical rocket RCS thrusters for thrust vectoring in a vacuum, during transition from orbital to atmospheric environments. In one respect, the Rhea is drastically different - it features a reduced troop compartment, capable of only carrying a miximum of twelve passengers, but compensates by its magnetic clamp.

Rather than a traditional magnet, the Rhea uses the LMG-112 Electromagnetic Clamp System - using the Olyndicus metamaterial as a powerful attractor, the clamp is capable of providing a firm grip on virtually any metallic material, not just the magnetised strips common on UNSC craft, allowing the craft to dock with virtually anything - during concept development, the system was also proposed as a means by which to board hostile ships after bypassing the shields, allowing insertion of Special Forces to capture the ship. This application has seen little development, though it was adopted for the planned Spartan-II operation, though again, never used.

Though the UNSC uses a number of craft that are described as VTOl, very few are actually operated that way. The Pelican, for example, is usually operated as a STOVL craft, using pre-existing runways for takeoff to save on fuel to increase the payload. The Rhea is a full VTOL craft, using its rotating thrusters to provide vertical thrust and then moving them to the flight position for horizontal thrust. Rather than conventional landing gear, it uses skids able to land on most surfaces, ranging from rough terrain to ice and snow. Some variants exchange this for conventional landing gear, trading fuel capacity for increased payload. Naval variants are equipped with grappling claws for docking with UNSC hangar facilities, allowing compatibility with most ship classes larger than a Corvette.

Quotes

 * "Kinda looks like a smaller, stubbier Pelican, doesn't it? Heh, I'm not complaining, at least its not the friggin' Petrel!"
 * "These thinks can haul a Scorpion like it's nothing. I'm not exactly sure what its maximum load is - what do we have that's heavier than a tank? An Elephant?"
 * "Its hard to see, but the Rhea's use skid landing gear rather than wheels. The Pelican was designed as a VTOL, but in practice its more like an STOL craft. Runways and such. The Rhea's have no such compunctions."
 * "They may not look like much, but its what they can carry that's important. When tanks were invented, the fastest way to get them to the battlefield was by train. And rails are pretty vulnerable. So now we go by dropship."
 * "If you look closely, there's handholds on the underside - the official story is that they're there for work crews. But my brother knows a guy who knows a guy who heard that it's so that Spartans can hang on when they're being airlifted out. Badass, right?"