Technical data Launcher Because of
SALT II agreements, no new launchers could be built, therefore the Pershing 1a M790 launchers were modified into the Pershing II M1003 launchers. The functions of the vehicle-mounted programmer test station needed for the older systems were consolidated into the Launch Control Assembly (LCA) in the Ground Integrated Electronics Unit (GIEU) on the side of the launcher. The warhead and radar sections were carried as an assembly on a pallet that rotated to mate with the main missile. There were two prime movers for the launcher, both with a crane used for missile assembly and a generator to provide power for the launcher and missile. The U.S. units used the
M983 HEMTT with a
Hiab 8001 crane and a 30 kW generator. Tactical units in Germany used the
M1001 MAN tractor with an
Atlas Maschinen GmbH AK4300 M5 crane and a 30 kW generator. Since the new guidance system was self-orienting, the launcher could be emplaced on any surveyed site and the missile launched within minutes.
Missile Motors The new rocket motors were built by Hercules: To minimize airframe weight, the rocket cases were spun from
Kevlar with aluminum attachment rings. The Pershing 1a cable mast was replaced by a conduit attached to each motor containing two cables. Cables internally connected from motor to motor and to the G&C. The aft end of the first stage had two tail plugs that connected to the GIEU.
Reentry vehicle The reentry vehicle (RV) was structurally and functionally divided into three sections: the radar section (RS), the
warhead section (WHS), and the
guidance and control/adapter (G&C/A) section.
Guidance and control/adapter The guidance and control/adapter (G&C/A) section consisted of two separate portions, the G&C and the adapter connected by a manufactured splice. At the forward end of the G&C there was a quick access splice for attachment to the warhead section. At the aft end, the adapter was grooved to accept the V-band that spliced the propulsion section to the G&C section. The RV separation system consisted of a linear shaped charge ring assembly bolted to the G&C section so that separation occurred just forward of the G&C manufactured splice. A protective collar on the outer surface of the adapter, mounted over the linear shaped charge, provided personnel protection during G&C/A handling operations. The G&C portion contained two guidance systems: a
Singer-Kearfott inertial
navigation system that provided guidance through the terminal phase and as primary terminal guidance system a Goodyear Aerospace
active radar guidance system. Using
radar maps of the target area, the Pershing II had an accuracy of
circular error probable. If the radar guidance failed, the inertial guidance would keep the missile on-target with a lower accuracy. The G&C also contained the Pershing Airborne Computer (PAC), the digital correlator unit (DCU) and actuators to drive the air fins.
Warhead section The warhead section contained the
W85 warhead, the rate gyro unit and the cables that passed from the G&C section to the RS.
Radar section The radar section consisted of the Goodyear radar unit with the antenna enclosed in an ablative
radome. The radar unit transmitted
radio waves to the target area during the terminal phase, received altitude and video information and sent the detected video and altitude data to the data correlator unit (DCU) in the G&C section. The highly accurate
terminal guidance technique used by the Pershing II RV was radar area correlation, using a
Goodyear Aerospace active radar homing system. This technique compared live radar video return to pre-stored reference scenes of the target area and determined RV position errors with respect to its trajectory and target location. These position errors updated the inertial guidance system, which in turn sent commands to the vane control system to guide the RV to the target. At a predetermined altitude, the radar unit activated to provide altitude update data and begin scanning the target area. The analog radar video return was digitized into two-bit pixels by the correlator unit and was formatted into a 128 by 128 array. The target reference scene data, loaded prior to launch via the ground and missile data links, were also encoded as two-bit pixels and placed in reference memory formatted in a 256 by 256 array. The reference scene resolution necessary to correspond to the decreasing altitude of the RV was effected by placing four reference data arrays in memory, each representing a given altitude band. This correlation process was performed several times during each of four altitude bands and continued to update the inertial guidance system until just before the impact. If for some reason the correlator system failed to operate or if the correlation data quality was faulty the
inertial guidance system continued to operate and guided the RV to the target area with inertial accuracy only. Goodyear also developed the Reference Scene Generation Facility, a truck-mounted shelter containing the equipment required to program the missile targeting controlled by a
DEC PDP-11/70. Radar maps of target areas were stored on disk, then specific targeting data was transferred to a
quarter-inch cartridge in a hardened carrier. During countdown operations, the cartridge was plugged into the launcher control panel to program the missile with targeting data.
Flight Prior to launch, the missile was referenced in azimuth by its
gyrocompass inertial platform. After launch, the missile followed an inertially guided
trajectory until RV separation. Attitude and guidance commands during powered flight (except for roll attitude) were executed via the swivel nozzles in the two propulsion sections. Roll control was provided by two movable air vanes on the first stage during first stage flight and by the RV air vanes during second stage flight. The first stage also had two fixed air vanes for stability during first stage powered flight. The midcourse phase of the trajectory was initiated at RV separation and continued until the terminal phase began. At the beginning of the midcourse phase, the RV was pitched down to orient it for reentry and to reduce its radar cross-section. The midcourse attitude was then controlled by the RV vane control system during atmospheric exit and reentry, and by a reaction control system during exoatmospheric flight. At a predetermined altitude above the target, the terminal phase would begin. A velocity control manoeuvre (pull up, pull down) was executed under inertial guidance control to slow down the RV and achieve the proper impact velocity. The radar correlator system was activated and the radar scanned the target area. Radar return data was compared to pre-stored reference data and the resulting position fix information was used to update the inertial guidance system and generate RV steering commands. The RV was then manoeuvered to the target by the RV vane control system.
Range The weapon had a range of . Soviet estimates put the system's range at and they also believed that the missile was armed with an earth-penetrating warhead. These two errors contributed to Soviet fears of the weapon, believing it could be used to
decapitate the Soviet Union. In reality, from positions in West Germany the system could not target Moscow. ==Deployment==