The SDY-Sciathan 18 Stuama is a light multirole fighter of Selkie-Design to be used as a carrier aircraft and ground-based aircraft, capable of acting as a fighter, bomber, fighterbomber, reconnaissance and patrol plane. Due to its high maneuvreability, the Stuama was also being discussed as a possible aircraft for the SDF Army and Navy Air Service Flight Demonstration Team, the Lincse.
The venerable Gaoth Fighterbomber was for quite some time well and truly outdated, the fleet in service with the SDF looking more like a vintage carpark then an air force (or rather Army Air Service and Naval Aviation Command as the case was).
With these bleak thoughts in mind, the SDF began to search for a replacement, making a bid to all available companies for a light multirole fighter. One of the answers was the SDY-Sciathan 18 Stuama Mark I, making its first flight in 2014, piloted by Kiah Eitil.
Mark II is the imporved version, the production model, making its first flight 2015. Serial production began in 2016, with Stuamas being supplied to both the SDF-Army and the SDF-Navy, as well as export customers. The total replacement of the fleet of Gaoths with the new Stuamas is expected to be completed in late 2017 with the last units to be replaced with the SDF-Navy's 2nd Naval Air Squadron.
The first update, not an upgade or an entirely new variant, is planned to be introduced in 2018, the Stuama Mark II-B, which will feature IRST, a system for infra-red search and track, and an enhanced radar warning receiver, enhancing the own capabilities in detection and knowing, when being detected. This will also include a software-upgrade.
Design: Mark II
The Stuama is a twin-engine, light multirole aircraft weighing 6.6 tons when empty. It is 15.4 metres long, has a wingspan of 9 metres and a height of 4.42 metres. It is equipped with modern air-search and fire control radars, as well as a downscaled battlescape network system permitting to send and receive data from other aircraft, ships, land units and even satellites (we tested it) without the need for a node in the network (although a node would increase the performance, we tested that as well).
The Stuama is equipped with two dispensers, one for flares as a countermeasure against heat-seeking missiles, the other for chaff against radar-guided missiles, making softkills against incoming missiles possible. As for Electronic Countermeasures, during operations, the SDF usually uses the under-fuselage hardpoint to mount an ECM-Pod, providing the Stuama with the capability to conduct operations in Electronic Warfare.
The airframe is a sleek, light and reinforced titanium-alloy construction with delta wings and smaller, canard wings for increased maneuvreability, reduced mainwing load and better control of the airflow. The two smaller empennages at the V-shaped tail increase the maneuvreability even further, resulting a small, powerful and highly mobile aircraft.
The aircraft is not capable to supercruise.
The Stuama is engined by two turbofan engines, Luas L-26 Mark II, the same as on the Veilbhit-II Light Attack Aircraft, with 30 kN dry thrust, 45.1 kN with afterburners. The R-87 is relatively easy to maintain for a turbofan engine. It is a highly effective low-bypass two-spool engine, using axial and centrifugal compressors to achieve higher pressure in the engine. It consumes 88.6 kg of fuel per kN and hour.
The Stuama is equipped with a modern X-band aircraft radar, capable of tracking twelve targets at a range of sixty kilometres. Together with the battlescape network system employed, the Stuama is capable of attacking targets far beyond that range, utilizing the maximum effective ranges of eventual air to air missiles.
Triple redundant fly-by-wire control systems steer the aircraft, based on modular architecture with dual redundant digital databusses. An inertial navigation system provides the pilot with data about speed, heading and position via the Head-up Display.