GBU-15 Guided Bomb Unit

The Guided Bomb Unit or GBU-15 is an unpowered, glide weapon used to destroy high value enemy targets. It was designed for use with F-15E, F-111F and F-4 aircraft, but the U.S. Air Force is currently only deploying it from the F-15E Strike Eagle.

The weapon consists of modular components that are attached to either a MK-84 general purpose or BLU-109 penetrating warhead. Each weapon has five components-- a forward guidance section, warhead adapter section, control module, airfoil components and a weapon data link.

The guidance section is attached to the nose of the weapon and contains either a television guidance system for daytime or an imaging infrared system for night or limited, adverse weather operations. A data link in the tail section sends guidance updates to the control aircraft that enables the weapon systems operator to guide the bomb by remote control to its target.

An external electrical conduit extends the length of the warhead and attaches the guidance adapter and control unit. The conduit carries electrical signals between the guidance and control sections. The umbilical receptacle passes guidance and control data between cockpit control systems of the launching aircraft and the weapon prior to launch.

The rear control section consists of four wings that are in an "X"-like arrangement with trailing edge flap control surfaces for flight maneuvering. The control module contains the autopilot, which collects steering data from the guidance section and converts the information into signals that move the wing control surfaces to change the weapon's flight path.

The GBU-15 may be used in either a direct or an indirect attack mode. In a direct attack mode, the pilot selects a target before launch, locks the weapon guidance system onto it and launches the weapon. The weapon automatically guides itself to the target, enabling the pilot to leave the area. In an indirect attack mode, the weapon is guided by remote control after launch. The pilot releases the weapon and, via remote control, searches for the target. Once the target is acquired, the weapon can be locked to the target or manually guided via the data-link system.

This highly maneuverable weapon has an optimal, low-to-medium altitude delivery capability with pinpoint accuracy. It also has a standoff capability. In Desert Storm, F-111F pilots used GBU-15 glide bombs to seal flaming oil pipeline manifolds sabotaged by Saddam Hussein's troops.

During 1999 to 2000, a large number of Legacy GBU-15 weapons received a significant upgrade in the ability to attack in adverse weather conditions by adding a Global Positioning System/inertial navigation system guidance capability. This important upgrade further enhances the warfighter's ability to attack targets, day or night. The enhanced GBU-15 weapon system was successfully employed in combat in 2001, directly supporting Operation Enduring Freedom combat operations.

The Air Force Development Test Center, Eglin Air Force Base, Fla., began developing the GBU-15 in 1974. It was a product improvement of the early guided bombs used during the Southeast Asia conflict. Flight testing of the weapon began in 1975. The GBU-15 with television guidance completed full-scale operational test and evaluation in November 1983. In February 1985, initial operational test and evaluation was completed on the imaging infrared guidance seeker.

In December 1987, the program management responsibility for the GBU-15 weapon system transferred from the Air Force Systems Command to the Air Force Logistics Command. The commands merged to become the Air Force Materiel Command in 1992.

During the integrated weapons system management process, AGM-130 and GBU-15 were determined to be a family of weapons because of the commonality of the two systems. The Precision Strike Program Office at Eglin AFB became the single manager for the GBU-15, with the Air Logistics Center at Hill AFB, Utah, providing sustainment support.

General Characteristics
Primary Function:
Air-to-surface guided glide bomb
Contractor: Boeing North American for Legacy version; Raytheon Systems for Enhanced version
Length: 12 feet, 10.5 inches (3.91 meters)
Launch Weight: 2,500 pounds (1,125 kilograms)
Diameter: 18 inches (45.7 centimeters)
Wingspan: 4 feet, 11 inches (1.49 meters)
Range: 5-15 nautical miles
Ceiling: 30,000-plus feet (9,091 meters)
Speed: Classified
Guidance System: Television or imaging infrared seeker via man-in-the-loop link, autonomous GPS/INS
Warheads: MK-84 general purpose or BLU-109 penetrating bombs
Date Deployed: Legacy, 1983; Enhanced, 2001
Unit cost: TV: $242,500; IIR: $245,000
Inventory: Classified