YDCh-17

YDCh-17
YDCh-17 missile with cross-section.
Type	Anti-tank guided missile
Place of origin	Menghe
Service history
In service	1998-present
Used by	See Operators
Wars	Ummayan Civil War Innominadan Crisis
Production history
Designer	Changgong Missile Design Bureau
Designed	1991-1997
Produced	1998-present
Specifications
Weight	47 kilograms
Length	2.24 meters
Diameter	133 mm
Wingspan	41 cm (fins extended)
Propellant	solid fuel rocket
Operational range	10 kilometers
Guidance system	Laser beam riding
Steering system	aerodynamic surfaces

The YDCh-17 (Menghean: 유도탄 대전차, Yudotan Daejŏncha, "missile, anti-tank") is an anti-tank guided missile developed in Menghe during the 1990s. It is longer than contemporary Menghean ATGMs like the YDCh-18, and offers greater range with a more versatile warhead. Because it relies on a direct impact rather than a top-attack approach, it has lost some of its usefulness against the newest main battle tanks, but it remains in service with the Menghean Armed Forces.

Design

To allow for a higher speed than a wire-guided missile would allow, the YDCh-17 uses a beam-riding guidance system. It can be programmed to follow one of two flight paths: a direct attack, in which the missile follows a straight line toward the target, and an elevated trajectory, in which the missile rises above the guidance beam until the final 800 meters to the target, at which point it descends to a direct approach again. The latter option reduces the risk of striking the ground en route.

Initial propulsion from the launch tube is provided by a quick-burning booster attached to the rear of the missile. Once the missile has left the launch tube, this module falls off, revealing the signal and receiver equipment in the base and allowing guidance to begin. Propulsion is then taken over by a solid-fuel sustainer section, which propels the missile by means of two angled ports in its sides. The rear stabilizer fins are slightly angled, inducing a spiraling flight path that increases stability and allows guidance with only two adjustable control surfaces.

The YDCh-17 uses a multipurpose warhead consisting of tandem HEAT charges in the forward section. The precursor charge is relatively large, measuring roughly 85 millimeters in diameter. Sources from the missile's development claim that this arrangement was intended to improve effectiveness against composite armor consisting of spaced steel plates: the first charge might defeat several plates before dissipating, while the second would be able to penetrate further, doubling the system's effectiveness without expanding the overall diameter of the charge. Reports of this arrangement's effectiveness, both in testing and in combat, remain dubious. The Menghean Army appears to have abandoned the "supercharged tandem" approach in subsequent missile development.

To further increase the missile's versatility, both HEAT warheads are surrounded by a prefragmented outer casing, with an additional high-explosive charge to the rear. This allows the same missile type to be used for a variety of targets, in contrast to the YDCh-18, which used separate anti-tank and anti-structure variants. It also makes the missile more effective against air-cushion landing craft, giving it an additional coastal defense role.

In 2006, the Changgong missile design bureau began work on a new YDCh-17 derived missile which would incorporate downward-facing shaped charges to defeat enemy tanks' top armor, in the same manner as the YDCh-70 which was then entering service. This proved difficult, however, as an overflight top-attack missile could not be spin-stabilized and would need an entirely new set of control surfaces. In the end, the General-Directorate for Procurement at the Ministry of National Defense opted to instead use the YDJ-48 and YDCh-72 top-attack missiles to deal with heavier main battle tanks.

Launch platforms

Due to its size and weight, the YDCh-17 is not primarily used as a man-portable weapon, though a remotely operated pack mount exists. Instead, it is primarily intended for use on fixed-wing aircraft, helicopters, and tank destroyer vehicles.

Air-to-ground versions

Several air-to-ground hardpoint adapters for the YDCh-17 missile exist, with the most common types mounting five tubes (three above, two below) or eight tubes (two rows of four). The following aircraft have been photographed with YDCh-17 missile launchers: Helicopters

• Gyundoan-Han GH-26 Agŏ
• Gyundoan-Han GH-28 Ppulsoeori (M variant only)
• GH-32 Byŏrakbul

Fixed-wing aircraft

• Songrim SR-3D1
• Daesŭngri DS-5D
• Daesŭngri DS-10

Y17G1 and G3 systems

Tank destroyer (left), platoon command vehicle (center), and battery command vehicle (right) of the Y17G1 anti-tank system. The Y17G3 system is identical except for the addition of new radio equipment.

Three-view diagram of the Y17G1B tank destroyer, as well as a cutaway view showing the missile storage carousels.

The designation Y17G1 refers to a family of tracked vehicles which together support the YDCh-17 anti-tank missile. The tank destroyer itself is designated Y17G1B, while Y17G1SS is a platoon command vehicle and Y17G1JS is a battery command vehicle. All vehicles use the same common chassis, which is derived from the BSCh-6 tracked APC, and are fully amphibious. The Y17G1B and Y17G1SS in particular have very low profiles, with the Y17G1B measuring 1.57 meters high to the roof - shorter than a standing soldier.

The Y17G1B tank destroyer has two ready missiles, which it carries on hinged loading arms. A total of twelve missile tubes can be carried internally on two six-missile carousels. Reloading is entirely automated: the carousels rotate to present an empty position, the arms swing down to replace their empty tubes, the carousels rotate to present a loaded tube, the arms grasp the mounting points, and the arms swing back up to the ready position. The carousel compartment is separated from the crew compartment by a steel firewall, which, in addition to protecting the crew in the event of an ammunition fire, also keeps the crew compartment sealed against chemical, biological, and radiological contaminants while the missile loading hatches are open. Each tank destroyer has a high-resolution visual and infrared camera unit with a laser designator which can guide up to two missiles toward a single target. The missile turret must traverse back to a direct-forward position while reloading, but the optical and guidance unit is separate, allowing the vehicle to reload its missile tubes while a guided missile is airborne. The entire reload cycle takes 15 seconds, excluding the time to correct the turret's traverse.

A drawback of the Y17G1B tank destroyer is that the commander has no optics unit separate from the gunner's, meaning that he can only search for new targets through his periscopes while the gunner is guiding a missile. To correct for this problem, each platoon is provided with a separate command vehicle designated Y17G1SS (sodae saryŏngcha, or platoon command vehicle). This vehicle carries the octagonal turret of the BSCh-5D IFV, sporting a 30mm autocannon, a 7.5mm co-axial machine gun, and a remote controlled 7.5mm GPMG on the CITV optical unit. The main difference is that instead of an ATGM launcher, the sides of the turret sport ground-surveillance phased array radars, which can scan the 180-degree arc in front of the turret for vehicles and infantry. The platoon command vehicle can also use its autocannon and machine gun armament to defend the tank destroyers against infantry, light vehicles, and helicopters.

In 2010 Menghe introduced the Y17G3 system, a successor to the Y17G1. The main change is the addition of MChGJ-0800 C-band radio systems to the launch vehicles and platoon command post. This allows the platoon vehicles to communicate and transfer target information over short distances with a reduced probability of alerting enemy SIGINT equipment to the anti-tank unit's location. Because new production had by that time shifted to Y48G2 systems, all Y17G3 systems are made from refis of existing vehicles.

In the Menghean Army, both the Y17G1 and Y17G3 systems are mainly used in anti-tank battalions at the divisional level. They have been issued to all existing Generation 2 reservist formations, but also persist in many Generation 3 active formations. Especially on the plains of Southern Argentstan, which allows land vehicles to exploit the YDCh-17's full range, these divisional anti-tank formations could be used to fill gaps in the front line or lay traps for enemy armored thrusts.

Rihwajaeng

The Rihwajaeng system is a portable land-based YDCh-17 launcher developed specifically for the Menghean Army's Coastal Defense Forces. It is named for the Rihwajaeng (Menghean: 리화쟁 / 梨花鎗, lit. "pear-blossom spear" or "pear-blossom gun"), an early gunpowder weapon used by Menghe's Yi dynasty. It was first deployed in 2007, and remains in widespread service with Coastal Defense units, where it serves at the battalion level.

The Rihwajaeng system consists of a tripod, a guidance camera, and two YDCh-17 missile tubes mounted side-by-side. It can be transported on a truck, usually a 4x4 Chŏnsŏ G544, and is capable of being fired while the vehicle is at a standstill. More importantly, however, the missile system can easily be dismounted and carried to a separate firing position, where it is set up on top of its tripod. Because the missiles are nearly two meters long and weigh some 50 kilograms each, this requires more preparation time than a typical man-portable anti-tank system. Operators are instructed to park the transport vehicle as close to the launch site as possible, and to carry the missile pair with one soldier at each end by means of a handle attachment included in the kit. A third crew member carries the tripod, and a fourth carries the remote aiming console and wire spool. Because the system is heavy and cumbersome, transport on foot is slow and full setup can take as long as fifteen minutes. For this reason, it is mainly intended as a defensive weapon, to be deployed well in advance of an enemy attack and abandoned during a retreat.

Once the tripod launcher is in place, however, the launch team can retreat to a safe distance and control it from there. The spooled wire allows the operator to retreat to a maximum distance of 200 meters, and this distance can be doubled by means of a second spooled wire carried in the transporting vehicle. Using the remote console with its digital screen, the operator has direct access to the launcher's camera, and can automatically elevate, traverse, and fire the system, guiding the system by means of the supporting equipment on the launcher itself. Individual launches and two-missile salvos are both possible.

The advantage of such a layout is that it allows the human operators to stay at a safe distance from the launch point, protecting them from suppressing fire directed at the missile's backblast cloud. Operators can even be stationed in an underground bunker or civilian structure, allowing them to man the system for weeks at a time - if the launcher's batteries run low on power, a generator can supply power along the same bundled wire used for control. It also means that the launcher, especially when concealed under a tarp, is much harder to detect on infrared reconnaissance cameras than a human operator would be. This makes it an excellent ambush weapon, able to cover a wide area with its range and offering little warning to its targets.

See also

• List of Menghean missiles
• YDCh-18
• YDCh-70
• YDCh-71