YDG-60

YDG-60
Type	Surface-to-air missile
Place of origin	Tír Glas, Menghe
Service history
In service	2006-present
Used by	Menghe
Wars	Innominadan Crisis
Production history
Manufacturer	Buksŏng Industries Group
Unit cost	$1.32 million (2020)
Produced	2001-present
Variants	YDG-60G, YDG-60N
Specifications (YDG-60G)
Weight	708 kg
Length	4.72 m
Diameter	340 mm
Wingspan	1.07 m
Propellant	Dual-thrust solid-fuel rocket
Operational range	165 km
Flight ceiling	24,000 meters
Speed	Mach 3.5
Guidance system	Semi-active radar homing (YDG-60G) Active radar homing (YDG-60N)
Steering system	aerodynamic surfaces

The YDG-60 is a Menghean licensed derivative of the Glasic SM-2MR Block IIIA. The production license for the weapon was originally granted in 2001, though the missile was not operationally deployed until the destroyer HJ-364 Haeju was commissioned on 30 May 2006. The sale of SM-2MR production rights to Menghe accompanied the licensing of the Mark 41 Vertical Launching System, also first introduced on the destroyer Haeju. Following the breakdown of relations with Maverica in 2005, Menghe also developed a land-launched version of the YDG-60 system.

Description

Both variants of the YDG-60 are vertically launched; Menghe does not operate any arm-launched variants of the SM-2MR, having licensed the Block IIIA version at the outset.

The YDG-60G has a two-stage guidance system. Its onboard autopilot, which uses an inertial navigation system, follows the most efficient route to the programmed intercept point, cruising at high altitude where air resistance is lower. During this stage of the course, the missile receives regular midcourse command updates from the launch platform, keeping it on course and correcting its path if the target changes direction, speed, or altitude in an effort to evade.

As the missile comes closer to the target, the guidance antenna (usually a STIR 2.4) switches on and illuminates the target, and the missile relies on semi-active radar homing for the final stage of its course. This final stage only requires a few seconds of radar illumination, allowing the launching ship or missile battery to fire multiple missiles at spaced intervals and guide them one at a time as they reach their intercept points.

Role

In the ship-launched role, the YDG-60 was originally intended to provide a medium-range air defense bubble for Menghean ships and formations at sea. The YDG-39, already in service, had a longer range at 200 kilometers, but it could only be fired from rotary cold-launch VLS tubes. The YDG-60, by contrast, was more compact, and compatible with Mark 41 VLS cells. When carried by the Yechŏn-class frigates, it gave these ships a much larger air defense bubble than the Ansa-class frigates that preceded them, and allowed them to launch missiles at shorter intervals.

After the licensing of the longer-ranged YDG-62 in 2006, the Menghean Navy transitioned to treating the latter missile as its main long-range defensive weapon, while the YDG-64 took over the medium-range anti-air role.

Around this same time, the Menghean Army expressed interest in the YDG-60, which could be used to equip corps-level air defense units. It became a central part of the Chŏlgung air defense system, carried first on the IMCh-J Koppulso universal chassis and later on the IMCh-D Pokgunryong universal chassis. Though inferior in range to land-launched YDG-39 and YDG-62 missile systems, the YDG-60 could be carried in shorter missile canisters and thus fit on a TELAR chassis more easily. Thus, by the 2010s the Menghean Army became the primary user of the YDG-60 in Menghe, and its land-launched YDG-60 systems use tactical-length vertical launch canisters even though no Menghean Navy ship carries tactical-length VLS cells.

Variants

YDG-60G

The first variant of the YDG-60 missile was the YDG-60G. It was a direct licensed copy of the SM-2MR Block IIIA, the first Glasic variant designed to be launched from Mark 41 VLS cells. The YDG-60G has better low-altitude performance than preceding SM-2 missiles, making it more effective against sea-skimming missiles, but it lacks the secondary infrared seeker carried by the SM-2MR Block IIIB. Instead, it relies on inertial midcourse guidance with command updates and terminal semi-active radar homing guidance.

YDG-60N

The YDG-60N is a major upgrade to the YDG-60, introduced in 2017. While the midcourse inertial and command guidance system is the same, the missile's nose cone contains an active radar homing guidance system. The Menghean Army ordered the development of this variant for its Chŏlgung-WR surface-to-air missile system as part of an effort to address two shortcomings of the YDG-60 system: each TELAR could only provide terminal guidance for one missile at a time, and if a target dropped below the radar horizon (or behind a mountain or forest), the missile would lose its lock. With an active radar homing system, however, the YDG-60N can autonomously home in on any target which falls within its seeker's acquisition basket, allowing multiple missiles to be guided simultaneously to multiple targets even if line-of-sight to the TELAR is broken.

The YDG-60 also added cooperative engagement capability, meaning that airborne early warning platforms with the correct datalinks can provide the missile with mid-course guidance if the launch battery's air search radar loses contact with the target. The combination of midcourse CEC and terminal ARH means that a Chŏlgung-WR battery can deploy in a city or forest with all of its radar antennas switched off and rely on other datalinked platforms to transmit target information and provide midcourse guidance. This makes the launch unit harder to detect and more resistant to SEAD efforts, as it does not switch on any of its own radar systems at any stage in the process. The airborne early warning platforms, however, are still vulnerable to jamming and destruction.

Chŏlgung-WR air defense system

Concept art of a Chŏlgung-WR long-range air defense battery stationed in Argentstan. Note the two Y64G2BR TELARs in the foreground and the Y64G2BG TELTs and Y64G2JSR 3D air search radar and command post in the background.

The YDG-60 is one type of missile used by the Chŏlgung air defense system, a family of surface-to-air missile systems in service with the Menghean Army. Batteries equipped with the YDG-60 are designated Chŏlgung-WR, with WR denoting wŏngŏri, or "long-range." This was the first component of the Chŏlgung air defense system to enter service.

Originally, the Menghean Army planned to use the IMCh-J Koppulso as the universal chassis for the Chŏlgung-WR air defense system. The Koppulso chassis was well-protected, had a proven record in service, and was also the basis for a number of other armored combat vehicles, including the JJP-152/48 self-propelled artillery gun. Army evaluators, however, were dissatisfied with this initial version of the Chŏlgung-WR system: because of the small size of the chassis, it was not possible to build a TELAR with both missiles and a guidance radar, only a TELT (transporter, erector, launcher, and transloader) with a self-loading crane. This meant that each battery could only provide terminal guidance for a single missile, using the command vehicle, which prevented the use of a battery-level air search radar. Furthermore, the battery-level missile transport could carry eight reload canisters, but it lacked a crane to load itself from cargo trucks, and it could not elevate and fire its onboard missiles.

This early version of the Chŏlgung-WR battery was structured as follows:

• 1 × battery command post (STIR 2.4 guidance radar)
• 2 × TELT (4 × YDG-60 and reloading crane)
• 1 × missile transport (8 × YDG-60, not launch capable)

As a solution, the Army ordered the development of a new Chŏlgung-WR system based on the IMCh-D Pokgunryong (Tyrannosaur) heavy common chassis. The IMCh-D is based on the hull of the JCh-6 main battle tank, but it is "stretched" forward with an additional pair of road wheels, has thinner side armor, and places the crew in a lightly armored cab overhanging the front of the tracks. The larger size and rear-engine arrangement of the IMCh-D allowed for the design of a TELAR with an onboard STIR 2.4 radar antenna, doubling the number of simultaneous missile illuminations which a single battery can perform. This change also eliminated the need for a guidance radar on the battery command post; instead, this vehicle was fitted with a 3D air search radar, allowing the battery to operate as a fully autonomous unit. Finally, the missile transport was replaced by a transloader with an onboard crane and the ability to launch missiles (though these would have to be guided by another battery vehicle).

This allowed for the following battery structure:

• 1 × battery command post (3D air search radar)
• 2 × TELAR (4 × YDG-60 and STIR 2.4)
• 1 × TELT (4 × YDG-60 and reloading crane)

According to some sources, while the TELAR and TELT are usually loaded with four YDG-60 launch canisters, each vehicle is capable of carrying up to eight. The additional canisters would be stacked in a second row above the existing four, using the coupling braces around the Menghean Army's modified Mk41 VLS canisters. A blurry still shot from footage of a Menghean Army firing range shows this eight-cell arrangement on a TELAR vehicle, and TELTs with this arrangement have been photographed in Argentstan. Independent analysts speculate that the eight-missile loadout may represent a maximum surge capability, with standard loadouts kept at four missiles during peacetime due to the cost of producing YDG-60 missiles.

See also

• YDG-62
• YDG-64
• List of Menghean missiles