Korea Aerospace Industries, in partnership with Hindustan Aeronautics Limited and the Korea Aerospace Research Institute, will be developing the Chamsaemae (Sparrowhawk) stealth helicopter frame, of which a number of variants will be developed.

Chamsaemae Modular Stealth Helicopter Frame

General Characteristics

The base Chamsaemae skeleton, from which the various variants will be added on to, will have a high-strength armored body, with the aim of being able to take a number of 30mm cannon hits. The shell will be of a modifier carbotanium, with the near-beta titanium alloy being Ti-10V-2Fe-3Al, known for its strength. The carbotanium will lead to a lightweight but durable frame. For stealth, rotor blades will incorporate design tactics to make them more quiet, even at a distance. Engines used will be the same Hanwha Techwin-produced GE T700s used on the KAI KUH-1 Surion, with the noise that engines give off not a stealth concern outside of quite close ranges. In addition, an active noise control system will be implemented to attempt and negate any remaining noise that the rotors give off. To reduce IR visibility, hot exhaust will be rerouted through an internal cooling system before being ejected.

The main electronics onboard will be a LIG Nex1-developed X-band radar, utilized to detect, track, classify, and monitor targets surrounding the helicopter at a range of up to 60 kilometers away. The radar should be able to detect everything from cruise missiles to UAVs to other helicopters, and will provide the user with a thorough picture of the combat environment.

In terms of countermeasures, a copper/bronze grid will be embedded into the primary rotor systems, as well as around major electronics within the helicopter. The detection system, led by the aforementioned X-band radar, will be directly linked to the active countermeasures system - which will release chaff and flare bundles within milliseconds of detecting incoming missiles - to avoid human error in this aspect.

The fuel tank - as well as the protective layer surrounding the electronics and surrounding the tail - will be insulated with self-healing materials specially designed to withstand heat. The nature of these self-healing materials is to be a temporary solution, until the helicopter can find its way back to a base for proper repair.

KUH-28 Chamsaemae Utility Helicopter Variant

The KUH-28 utility variant will be the closest to the base system. The only real changes will be increased up armoring on the side doors, as well as the front ramp, with increased kevlar designed to protect infantry.

KAH-28 Chamsaemae Attack Helicopter Variant

The KAH-28 attack helicopter variant will forego additional protections in favor of heavy land-based armament, including a front-mounted 30mm chain gun in a stealth cupola, four hardpoints on which rockets of air-to-surface anti-tank/anti-infantry missiles can be attached, and another 20mm gatling-type rotary cannon mounted further back on the body.

KMH-28 Chamsaemae Marine Helicopter Variant

The KMH-28 has a high degree of similarity with the base KUH-28 variant, bar the uparmored doors. In place of the weight of the uparmored doors, there will be a integrated flotation system, auxiliary fuel tank, specialized radio equipment, and folding main rotor - all of which will be taken from the MUH-1 Marineon. There will also be slightly more weaponry, to allow for the KMH-28 to play a “mixed” transport/attack helicopter role.

KAsH-28 Chamsaemae Anti-Submarine/Shipping Helicopter Variant

The KAsH-28 will be extremely similar to the KAH-28, with the exception that the hardpoints will be adapted to fit SSM-710KL Haesong anti-ship missiles, an adapted version of the upgraded SSM-710K Haesong anti-ship missile, or Blue Shark torpedoes. The folding main rotor will be adopted from the KMH-28 as well.

Development will take 3 years, ready by 2031, and will cost $8 billion total. Unit costs will range anywhere from $8 million for the KUH-28 base variant to $11 million for the KAH-28 and KAsH-28 highly modified variants

Initial production will be as follows, spread out over 4 years.