Developed in YE 33 by Chusa Kage Yaichiro, the Dual Stage Aether Drive is a Project THOUGHT design intended to serve as a replacement of the stand alone Turbo Aether Plasma Drive Drive. It takes the data of the Aether-heated Jet Engine from the Tsubame Prototype Fighter and feeds it back into the propulsion program by combining the functionality of the two into a single hybrid engine for use in a friendly planet’s atmosphere as well as in space.
The Dual Stage Aether Drive is a hybrid engine which is capable if delivering two forms of propulsion. While it is not difficult to detect when in use as it needs an Aether Generator to function; it is cheap and its configurations allow for air travel, aquatic travel, attaining escape velocity from a planet, and space travel. It is not designed for stealth, and is geared toward replacing the stand alone Turbo Aether Plasma Drive Drive with something more diverse.
Though it costs more than a stand alone Turbo Aether Plasma Drive Drive, its use in a biosphere is far safer. It is also designed to be placed into many chassis, and even has potential for use in units with thrust vectoring capabilities. Compared to other forms of STL, it is still cheap.
When in Stage 1, the Dual Stage Aether Drive acts as a Aether-heated Jet Engine. This is the primary method of operation in atmosphere or underwater, where heat from the Aether generator is used to combust the air or heat the water and make it expand without the need for fuel. Rather than using a conventional intake fan, rotating and specially shaped forcefields near the intake are typically utilized when at low speeds, which change angle of attack or are even deactivated when the speed of the air or water coming in high enough. This not only allows the intake to be micromanaged by the computer for optimum efficiency and acceleration, but also allows the engine to operate as a Ramjet. Most such engines are capable of a top speed of 7,163 kph/4,450 mph in standard atmosphere (roughly Mach 6 at sea level); but the structural integrity of the craft, materials used for construction, and heat tolerances must all be taken into consideration when rating speed.
Stage 2 is a mode in which the Dual Stage Aether Drive operates as a Turbo Aether Plasma Drive Drive, like those used on most modern Star Army of Yamatai craft. It boasts the same performance and capabilities, making it a plausible upgrade function for Star Army craft. Typically the intakes are sealed by armored shutters at this stage to prevent damage from enemy weapons fire. This is considered a fast engine and in the Very Advanced Technology class, giving it a speed of roughly 0.375c (112,422 km per second), but this varies on the specific model.
This mode, like the existing Turbo Aether Plasma, should not be used in atmosphere heavily or in populated areas, and the exhaust trail has the same destructive output(Tier 9, Heavy Anti-Mecha-Tier 11, Medium Anti-Starship on a starship). As they are based on Star Army of Yamatai designs, they have a teal glow. While the signs of Turbo Aether Plasma remain detectible for weeks, the actual potential for causing damage is only present for a matter of minutes. Due to this, it can safely be used at higher altitudes and for achieving escape velocity if throttled back to pre-determined levels.
While a powerful design which allows STL movement in most situations, the Turbo Aether Plasma Drive elements used for Stage 3 forbid the use of the technology in the civilian sector. Space testing was conducted with the Two Stage Laser Engine, a system derived from the Aether-assisted Laser Engine first designed for the Tsubame Prototype Fighter.
As the system is made of existing technology which has been reapplied, rather than anything groundbreaking, the price of the drive allows it to be a prime candidate for mass production. The cost is a bit greater than a standard Turbo Aether Plasma drive, but the ability to use the system in all roles more than cancels this out.
While it can be mounted to normal engine mounts, the engine can also be used with the jointed developed by Project THOUGHT, such as the Project THOUGHT Frictionless Hybrid Joint and the Project THOUGHT Simplified Joint. Due to this, it is not uncommon for these joints to be used for thrust vectoring capabilities. This is only if the frame of the equipped craft can handle the stresses of thrust vectoring, and the range of motion may also be limited by what the frame can handle.
While not the stealthiest system, this type is capable of most kinds of space and terrestrial STL, and is never more detectible than the unit it replaces. Due to this, it is more versatile than the Turbo Aether Plasma Drive, though other types of propulsion may be better for specific mission profiles.