Weapons
Development Progress
AGM-12 Bullpup
The Bullpup was one of the first mass-produced, guided air-to-surface missiles and entered service before the Vietnam war. It was a Manual Command Line of Sight, or MCLOS missile, which meant that the guidance was provided by the pilot through manual steering inputs.
DCS currently features three variants of the Bullpup, the AGM-12A, the original 1958 variant for the Navy with a 250 lbs warhead and an Aerojet Mk 8 solid motor (initially designated ASM-N-7), AGM-12B, the 1960 improvement with a Thiokol LR58 liquid rocket motor (USN ASM-N-7a and USAF GAM-83A designations), and a 1964 derivative with a much larger warhead and an LR62 liquid rocket motor: the AGM-12C. 3D models were provided by Heatblur Simulations.
All variants of the AGM-12 featured a canard, cruciform aerodynamic configuration and a bang-bang steering system stabilised through a 500°/s roll rate. In addition to the engine nozzle, the rear of the missile included a pair of tracking flares that burned with an increasing intensity over time. To improve the controllability of the missile, the bang-bang canard steering was modulated. Effectively the canards deflected in short pulses, whose length and frequency depended on both the angle of deflection and the rate and duration the stick was moved. A basic form of auto-trim was also used.
One major limitation of the system was a tendency for the control axis to roll left because the roll rate increased during the deceleration to the transonic region. This was caused by delays in the control system. This was compensated for by adding a fixed offset to the roll gyro reading that did not depend on the actual roll rate. All these effects on the control system are fully modelled in DCS.
Rockwell Homing Bomb System
After the AGM-62 Walleye was introduced by the US Navy in 1967, the USAF awarded a contract for their own TV-guided bomb system to Rockwell. This resulted in a series of conversion kits for dumb bombs, dubbed HOBOS, or the Homing Bomb System. These kits consisted of an electro-optical nose seeker section, an aft control section, and a set of strakes running along the body of the bomb. The seeker and guidance used were similar to those on the AGM-62 and AGM-65, and it required the pilot and WSO to align the aircraft with the target using the seeker video feed and lock onto target contrast before release, proving to be difficult in practice.
Different daytime electro-optical and infrared seeker kits were developed for different types of bombs, of which only the KMU-353A/B kit for the Mk-84 low drag bomb saw extensive combat use. This configuration, designated GBU-8/B by the USAF, was used from 1969 onward, and is featured in DCS. The 3D model is provided by Heatblur Simulations.
GBU-15(V)/B
Despite the low effectiveness of the HOBOS, Rockwell was again contracted to continue their guided-bomb development in 1974. The result was a modular system that Rockwell referred to as Modular Guided Weapon System or MGWS. This resulted in the GBU-15(V)/B family of guided-bombs, also known as the Electro-optically Guided Glide Bombs, or EOGB.
Initially, two variants were developed: The GBU-15(V)1/B with a daylight seeker and the GBU-15(V)2/B with the same IR seeker as the one used for the AGM-65D. The configuration was similar to its predecessor, the GBU-8/B, with the Mk-84 also serving as a basis of this weapon. However it had a significantly larger set of “wings”, a more sophisticated guidance system, and an ability to communicate with the supporting launch aircraft through the AN/AXQ-14 datalink.
These new features significantly expanded the envelope of the weapon at low altitudes compared to the GBU-8/B, and it allowed for employment without a line of sight to a target at the time of release. The weapon followed a 3-stage guidance logic: After a separation manoeuvre, the weapon entered midcourse mode where it would follow a lofted trajectory along the release course. After the WSO spotted and identified the target, they would point the seeker at it and switch the weapon to transition mode. It would then turn to target heading and manoeuvre to keep the seeker at a constant look-down angle, allowing the WSO to adjust the impact angle. Finally, the WSO would select terminal guidance mode in which the bomb would either be automatically guided into impact if locked on, or flown into the target manually.
The GBU-15 is in development.
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