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Guided Bomb Unit-24 (GBU-24)
Paveway III

The Guided Bomb Unit-24 (GBU-24) Low Level Laser Guided Bomb [LLLGB] consists of either a 2,000-pound MK-84 general purpose or BLU-109 penetrator bomb modified with a Paveway III low-level laser-guided bomb kit to add the proportional guidance in place of the bang-bang type used in the Paveway II. The LLLGB was developed in response to Sophisticated enemy air defenses, poor visibility, and to counter limitations in low ceilings. The weapon is designed for low altitude delivery and with a capability for improved standoff ranges to reduce exposure. The GBU-24 LLLGB/Paveway III has low-level, standoff capability of more than 10 nautical miles. Performance envelopes for all modes of delivery are improved because the larger wings of the GBU-24 increases maneuverability. Paveway III also has increased seeker sensitivity and a larger field of regard.

The operator illuminates a target with a laser designator and then the munition guides to a spot of laser energy reflected from the target. One way to deliver LGBs from low altitude is a loft attack. In this maneuver, the aircraft pulls up sharply at a predetermined point some miles from the target and the LGB is lofted upward and toward the target. However, if the LGB guidance system detects reflected laser energy from the target designator too soon after release, it tends to pull the LGW down below its required trajectory and the bomb will impact well short of the target.

This bomb is not nearly as delivery parameter sensitive as is the Paveway II LGB, nor is it affected by early laser designation. After a proper low altitude delivery, the LLLGB will maintain level flight while looking for reflected laser energy. If it does not detect reflected laser energy, it will maintain level flight to continue beyond the designated target, overflying friendly positions, to impact long, rather than short of the target.

Unlike the Paveway II LGB, the LLLGB can correct for relatively large deviations from planned release parameters in the primary delivery mode (low-altitude level delivery). It also has a larger delivery envelope for the dive, glide and loft modes than does the earlier LGB. The wide field of view and midcourse guidance modes programmed in the LLLGB allow for a "Point Shoot" delivery capability. This capability allows the pilot to attack the target by pointing the aircraft at the target and releasing the weapon after obtaining appropriate sight indications. The primary advantage of this capability is that accurate dive/tracking is not required to solve wind drift problems.

In the Gulf War all of the 1,181 GBU-24s were released by F-111Fs.

In 1996 the Navy conducted tests of the F-14A Tomcat with the GBU-24B/B Hard Target Penetrator Laser-Guided Bomb at Naval Air Station Patuxent River, Md., as part of an air-to-ground development program to support clearance for use of the weapon in the fleet by F-14 Tomcats.

Key accomplishments in 1996 included demonstration of controlled weapon penetration and detonation depth using the Hard-Target Smart Fuse [HTSF] and successful integration of the GBU- 24/ HTSF with F-15E and F/A- 18 aircraft. The Hard-Target Smart Fuse, developed at the Wright lab, features an accelerometer that can be programmed to detonate the bomb at a precisely specified depth significantly enhancing munition lethality. The Defense Special Weapons Agency (DSWA) Counterproliferation Initiative (CPI) requires development, integration and certification of HTSF with GBU-24 B/B (Navy BLU-109) and GBU-24 D/B (Navy BLU-116) under this effort. Under a separate effort, CPI will integrate the GBU-24 B/B and GBU-24 D/B configuration HTSFs into the CPI modified Conventional Air Launched Cruise Missile (CALCM) and Tactical Land Attack Missile (TLAM) weapons.

The Multi-Segment Hard Target Penetrator (MSHTP) concept has been designed to use the penetration capability of a BLU-113 or BLU-109 linked to the void counting hard target smart fuse. This weapon detonates a copper cutter charge upon entering the target and cuts the rear portion of the bomb off, which then detonates. The rest of the weapon continues down to the next level.

BLU-116 Advanced Unitary Penetrator [AUP]
GBU-24 C/B (USAF) / GBU-24 D/B (Navy)

Air Force Research Laboratory Munitions Directorate engineers have completed development of a new warhead known as the Advanced Unitary Penetrator, or AUP. The warhead was successfully transitioned to the Precision Strike System Program Office at Eglin AFB, Fla. for Engineering Manufacturing Development (EMD) and production. The AUP was developed in less than three years at a cost of less than $8M. AFRL's emphasis on operational suitability as part of AUP weapon design will allow the EMD program to be completed in less than half the time of a normal EMD program.

The Advanced Unitary Penetrator [AUP] hard target penetrator features an elongated narrow diameter case made of a tough nickel-cobalt steel alloy called Air Force 1410. With the official designation of BLU-116, and designated the GBU-24 C/B (USAF) and GBU-24 D/B (Navy), is designed to provide at least twice the penetration capability of existing BLU-109 2000-pound bombs. The AUP is being demonstrated with Boeing as prime and Lockheed-Martin as subcontractor. Penetration capability is directly proportional to the warhead's sectional density--its weight divided by its cross section. The AUP maximizes sectional density by reducing the explosive payload and using heavy metals in the warhead case. Lower explosive payload will diminish dispersion of NBC agents to help reduce collateral effects. The AUP will retain the carriage and flight characteristics of the BLU-109, and it will be compatible with the GBU-24, GBU-27, and GBU-15/AGM-130 series of precision-guided bombs. Thus, the AUP will be capable of delivery from a wider inventory of aircraft, including stealth platforms, than the BLU-113/GBU-28. A proposal to replace the current CALCM warhead with an AUP warhead provides 2.5 times BLU-109 penetration capability.

The AUP development effort was conducted in support of the Counterproliferation Initiative (CPI) Advanced Concept Technology Demonstration (ACTD). The program objective was to develop and demonstrate a weapon that could be rapidly transitioned for Air Force and Navy use against hardened targets associated with the production, storage, and weaponization of chemical or biological agents. Normally, the introduction of a new weapon is a very long, expensive, and tedious process - as long as ten years or more. The associated cost may be tens of millions of dollars.

The 1700-pound AUP warhead is tucked inside a lightweight aerodynamic shroud. This "outer skin" gives the AUP the exact physical and aerodynamic characteristics of the BLU-109. The shroud strips away from the internal penetrator when the weapon impacts the target. Compared to the BLU-109, the AUP has thicker case walls, a tougher case material, an improved nose shape, and a smaller explosive charge. The cross-sectional area of the AUP penetrator, however, is only half as great as the cross-sectional area of the BLU-109. A smaller explosive charge reduces collateral damage potential by reducing blast overpressure that could expel chemical or biological agents from the target. A long testing series demonstrated AUP's compatibility with the Munitions Directorate-developed Hard Target Smart Fuze (HTSF). The HTSF allows the AUP to be detonated at the optimal point within a target to inflict maximum damage. That ability compensates for the reduction in explosive charge.

Because it's a "twin" to the BLU-109, the AUP can utilize a proven system of hardbacks, guidance units, and tail fin kits. The costs associated with developing new kits is eliminated. The operational users - pilots, weapon handlers and load crews - will gain the improved war fighting capabilities of the AUP without the costs associated with retraining support personnel or the acquisition of new delivery systems and support equipment. Battle commanders will also have increased ability to neutralize deeply buried hardened targets.

GBU-24 E/B

GBU-24E/B, an Enhanced Paveway Laser Guided Bomb, is a precision-guided hardened target penetrator used to destroy hardened aircraft hangers and underground bunkers. It integrates a Global Positioning System and a ring laser gyro inertial measuring unit (IMU) to the already fielded GBU-24B/B "Paveway III" with the existing laser guidance. A new guidance and control unit has been modified to incorporate GPS electronics, GPS antenna, IMU and software for precision GPS/INS guidance. Testing of this system began in late 1999.

Specifications

Mission Close air support, interdiction, offensive counter air, naval anti- surface warfare
Targets Mobile hard, fixed soft, fixed hard
Service Air Force, Navy
Program status Operational
First capability 1983
Guidance method Laser (man-in-the-loop)
Range Greater than 10 nautical miles
Development cost Not available - Air Force officials stated that development cost was not available because they do not have records covering the development period.
Production cost $729.138 million
Total acquisition cost Not available
Acquisition unit cost Not available
Production unit cost $55,600
Quantity 13,114
Platforms A-6
A-10
F-14
F-15
F-16
F/A-18
F-111

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Updated Monday, December 27, 1999 5:25:18 PM