9M111 / SA-19 GRISON
The SA-19 GRISON (9M111) is a radar command guided, two-stage surface to air missile mounted on the 2S6 Tunguska Integrated Air Defense System. The 2S6 vehicle is fitted with two banks of four missiles in blocks of two, which can be elevated vertically independent of each other. The SA-19 can engage aerial targets moving at a maximum speed of 500 meters/second at altitudes ranging from 15 to 3,500 meters, and at slant ranges from 2400 to 8000 meters. The missile's high-explosive fragmentation warhead is actuated by a proximity fuse if the missile passes within 5 meters of the target. The SA-19 is claimed to have a kill probability of 0.65.
The SA-19 missile is a two-stage command-guided missile. The missile system is composed of the fire control unit, launcher, missile tracker, and the canistered missile, and is supported by the direct-view optics (DVO) and the HOT SHOT target tracking and acquisition radars onboard the 2S6M. Typical reaction time is 8-12 seconds.
During a missile action the radar first locks on the target, as in the case of gun employment, and then lays the slaved optical sight on the target. Subsequently the gunner assumes target tracking functions through his optical sight, and the radar is used for relaying the trajectory correction commands to the missile in flight. Immediately prior to the launch, the turret is turned slightly off-axis, so that the smoke caused by the launch will not obstruct the sight on the target.
The 2S6M must be stationary during the launch sequence, in order to avoid damage to the missile while it leaves the launch tube. Immediately after launch, the weapon system is lowered again into the lock position (-60) in order to keep the line of sight free and because the turret is not moved during the target tracking.
The missile is accelerated to around 900m/s (Mach 3) by a rocket booster. After the booster is jettisoned, a pulsed light source in the missile's tail is activated, allowing automatic tracking of the missile in flight by the optical sight. During the entire flight time of the missile, the gunner must constantly maintain the crosshair of the optical sight on the target; the deviation of the missile's flight path form the line-of-sight is automatically computed and used to generate course correction signals. These are then transmitted to the missile in flight through the tracking radar, which during a missile engagement sequence doubles as fire-control radar. Missile employment is only possible in daylight and fair visibility conditions, because the target needs to be tracking with the optical sight for the entire duration of the engagement sequence.
The radar and fire-control system of the 2S6M can be employed in five different operating modes:
- Mode 1: Automated radar tracking. This is the main operating mode.
- Mode 2: Manual electro-optical angle track with range data from either radar.
- Mode 3: Inertial tracking.
- Mode 4: Radar on manual electro-optic angle track with range estimation.
- Mode 5: Ground target engagement.
In the main operating mode, after the tracking radar has locked-on to a target, tracking is automatic and most data are relayed directly to the computer. The optical sight can either be slaved to the line-of-sight to the target (in preparation for the missile launch) or used independently for further target acquisition. The weapons are laid automatically and the crew's tasks are limited to selecting the weapons and pressing the fire key; when the missiles are used, as previously indicated the gunner must keep his sight on the target for the entire duration of the engagement sequence. The remaining three operation modes are intended for degraded conditions, bypassing a failed subsystem or replacing it with an alternate working mode. However, these modes produce lower accuracy and/or slower operation and the vehicle must be stationary. The fifth mode is applied during the engagement of ground targets. The radar system is shut off, and a reticle is inserted into the optical sight; the lead angle is automatically computed according to bearing and distance, and the laying speed is then proportional to the movements of the gunner's control stick.
As of August 2007, Google was aware of about 825 instances of "SA-19 Grison" and over 2,700 instances of "SA-19 Grisom". At that time, Google was aware of about 24,000 instances of the word "Grisom" other than those related to the SA-19. Essentially all of these other instances of the word "Grisom" [not to be confused with the "Grissom" of the astronaut Virgil Ivan "Gus" Grissom, of which there were about 2,000,000 instances] were proper names that had no sensible connection with an anti-aircraft missile. While older references to this missile tended towards "Grisom", more recent and authoritative references have tended towards "Grison". While the naming convention for Russian missiles does not require that the name be directly associated with the type of system, it does generally require that the name be an actual word, rather than an arbitrary assemblage of letters that some people have used as their proper name. The word Grison is both an actual word, and as a hunting animal Grison is a good name for an anti-aircraft missile.
The name "Grison" comes from the French word "gris," which means "gray." The Grison (Galictis vittata), or Gray Weasel, is a carnivore found in Central and South America, in woodlands and grasslands, also found near inhabited buildings, at an altitude up to about 4000 feet. The coat consists of long, soft hairs. A white stripe runs from the forehead over the ears as far as the shoulders, and separates the black face, throat, and chest from the grizzled gray back. The general appearance is ferretlike with a long body and short legs, but the color pattern is distinct. The head and body are about 20 inches long, with a tail of about six inches. The weight is three to seven pounds. Allamand's grison (G. allamandi), with the same range, is somewhat larger. Another member of the genus is the tayra or taira (G. barbara), about as large as an otter, with a range from Mexico to Argentina. This species hunts in companies. The grison, known as the huron in Spanish and furao in Portuguese, hunts both night and day, and is often seen in small groups. They live in crevices in rocky areas and beneath tree roots. They feed on chinchillas, viscachas, and other rodents, which they kill with a swift bite on the back of the neck. They can cause damage to domestic animals, but are also used to combat rodent infestations or to hunt chinchillas, just like ferrets are used in Europe to hunt rabbits.
A single entirely authoritative source refers to this missile as the GRENDEL. This designation is otherwise un-attested. The epic of Beowulf, the most precious relic of Old English, and, indeed, of all early Germanic literature, came down in a single MS., written about A.D. 1000. Beowulf, with fourteen companions, sails to Denmark, to offer his help to Hrothgar, king of the Danes, whose hall (called "Heorot") has for twelve years been rendered uninhabitable by the ravages of a devouring monster (apparently in gigantic human shape) called Grendel, a dweller in the waste, who used nightly to force an entrance and slaughter some of the inmates. Beowulf, unarmed, wrestles with the monster, and tears his arm from the shoulder. Grendel crawls away, and dies. The water-demon Grendel and the dragon (probably), by whom Beowulf is mortally wounded, have been supposed to represent the powers of autumn and darkness, the floods which at certain seasons overflow the low-lying countries on the coast of the North Sea and sweep away all human habitations; Beowulf is the hero of spring and light who, after overcoming the spirit of the raging waters, finally succumbs to the dragon of approaching winter.
At one time, it appeared that the "Pantsyr S1" nomenclature was associated with this missile, but by 2007 it was apparent that this nomenclature was properly associated with the Pantsyr S1 short-range air defense missile-gun system which will replace the Tunguska M1 complex which employs the 9M311 / SA-19 GRISON missile.
The designation "SA-N-19 GRISON" is evidently nothing more than a typographic error.