The OTR-23 OKA 9K714 (NATO Code name SS-23 Spider) is a Soviet-made short-range road-mobile theatre ballistic missile. The system is based on an 8x8 truck chassis with one 9M714 surface-to-surface ballistic missile carried at the rear of the chassis. The SS-23 was entered in service with the Russian armed forces in 1980 but it is not currently used. The SS-23 missile has a longer range compared to the SS-21 Scarab. The system was exported to some countries at the East Germany, Bulgaria and Czech Republic. The systems were eliminated under the Treaty on the elimination of intermediate-range and short-range missiles dated of December 8, 1987. The SS-23 was replaced in the Russian army by the SS-26 (Iskander-M). According a news of TASS Russian news agency from June 2015, Russia is developing an upgraded version of the 9K714 Oka tactical missile system.
The rear part of the SS-23 Spider TEL (Transporter Erector Launcher) vehicle encloses one ballistic missile. In road position, the missile is carried inside an enclosed cabin. The missile is erected at the rear of the vehicle in firing position. To prepare the SS-23 Spider for firing, two hydraulically operated spades are lowered on the rear side of the chassis to stabilise the vehicle.
Missile and warhead
The SS-23 can launch three types of missiles as the 9M714B armed with a nuclear warhead, the 9M714F armed with a FRAG-HE warhead and the 9M714K armed with a sub-munitions warhead 9N74K. The weight of the payload varies between 715 and 772 kg depending on the type of warhead. The missile uses an inertial guidance system coupled with an active radar terminal guidance system. This provides an accuracy of 30 m CEP with a maximum range of 500 km. The OTR-23 is 7.32 m long, 0.89 m in diameter and has a launch weight of 4,360 kg. The missile uses a single-stage solid propellant engine.
SS-23 Spider (OTR-23 9K714 OKA) 9M714 missile
Design and protection
The SS-23 Spider is based on the BAZ-6944 with engine and crew cabin mounted at the front of the vehicle. The rear part of the vehicle is used to carry the missile. The crew prepares missile for launch and calculates flight trajectory from inside the cabin. The BAZ-6944 has an NBC (Nuclear, Biological, Chemical) protection system with a pressurized compartments.
Mobility
The SS-23 Spider uses an 8x8 military truck chassis BAZ-6944 motorized with V-twin diesel engine UTD-25 developing 400 hp. Transmission consists of a five-speed hydraulic transmission, two-speed transfer case with inter-side stowing differential, cardan gear, flight gear and wheel gear. The vehicle can run at a maximum speed of 65 km/h with a maximum cruising range of 700 km. The vehicle is fully amphibious and propelled in the water thanks to two water-jets mounted at the rear of the chassis. In the water, it can swim at a maximum speed from 8 to 10 km/h.
Combat use
The main components of the SS-23 system were: - the transport and launch vehicle (TEL) PU 9P71or 9K714 based on the amphibious BAZ-6944; - the transporter-loader TZM 9T230 with one spare missile and equipped with a hydraulic crane; - the re-supply vehicle TM 9T240, a ZIL-131 tractor with semi-trailer to transport a missile (in transport container 9Ya249) and a warhead (in 9Ya251 container). The SS-23 tactical vehicle is greatly augmented by mobility and the speed of the system. It has a reaction time of less than 30 minutes.