Do not approach munitions
under any circumstances

OSMP Collection

What Are Bomb Guidance Kits?

Bomb guidance kits are fitted to unguided (‘dumb’) bombs to convert them into precision guided munitions (PGMs). Sometimes referred to as ‘bolt-on’ guidance kits if they are relatively simple to install, bomb guidance kits can provide a variety of capabilities that vary according to cost and what the user needs.

Most guidance kits replace the fixed fins of an unguided air-delivered bomb with actuated fins that can ‘steer’ the munition as it falls. Some kits will also include additional or alternative guidance or control components in the nose of the munition. These additional components frequently survive detonation of the bomb, and can be diagnostic in identifying the family or model of munition used.

This entry in the OSMP shows a MK 84 unguided air-delivered bomb fitted with a JDAM guidance kit, but how can you distinguish the munition from the guidance kit? The illustration on the right explains (source: IDF Farsi).

The way guidance is achieved varies by kit, but Global Position System (GPS) data, inertial navigation system (INS) data, laser guidance, and electro-optical (EO) guidance are common.

Some common kits are the U.S. Joint Direct Attack Munition (JDAM) kits, which use GPS/INS guidance, and the Israeli SPICE 1000 and SPICE 2000 kits, which use EO and GPS/INS guidance. The U.S. Paveway and Israeli LIZARD series use laser guidance.

When munitions are combined with a guidance kit, they are sometimes given a new designation by manufacturers or in military service, such as the U.S. ‘Guided Bomb Unit’ (GBU) designation. For example, when a 2,000-pound MK 84-series air-delivered bombs is fitted with a JDAM kit, it is referred to as a GBU-31. Combinations may have further variant designations, such as GBU-31(V)1, etc.

In this illustration, the main parts of a U.S.–made JDAM bomb guidance kit are shown in grey, while a MK 80 series bomb body is depicted in white. This image was modelled on a MK 84 unguided air-delivered bomb fitted with a KMU-556/B JDAM kit. The combination of these components is referred to as a GBU-31(V)1/B in U.S. service.
  1. MK 84 Bomb: Explosive section of the munition
  2. Strakes: Aerodynamically stabilised surfaces
  3. Guidance Control Unit: Delivers commands to the tail actuation section
  4. Tail Actuation Section: Controls the tail fins to alter the munition’s course in flight
  5. GPS Antenna: Receives location data
  6. Actuated Fins: Helps to steer the bomb

Methodology

This collection filters all images from the OSMP which show both guidance kit debris as well as air-delivered bombs of different weights which have had guidance kits attached to aid targeting.

Images in collection

28

Munitions in collection

Analyst Note:
This image shows an aerosurface or ‘strake’ from a Joint Direct Attack Munition (JDAM) bomb guidance kit of the type fitted to MK 82-series 500-pound air-delivered bombs. The JDAM kits compatible with MK 82 bombs have aerosurfaces that are affixed near the nose of the bomb—rather than around the widest part of the bomb body, as seen in JDAM kits that are compatible with the larger MK 83 or MK 84 bombs. (ARES)
Analyst Note:
The RAFAEL Advanced Defense Systems SPICE 1000 guidance kit is fitted to MK 83-series 1,000-pound unguided air-delivered bombs to convert them to precision guided munitions. Like the JDAM-ER, it has a deployable wings to provide a ‘gliding’ attack trajectory. (ARES)
Analyst Note:
The BLU-117 air-delivered bomb is nearly identical in format to the more common MK 84, but uses the PBXN-109 explosive filler which is more insensitive than the typical explosive compositions found in MK 80-series bombs. The BLU-117 is also coated with a grey, thermally resistant paint, and marked with three yellow bands (as opposed to the green paint with two yellow bands found on standard MK 80-series bombs). These changes were requested by the U.S. Navy for safer storage of these munitions aboard ships. (ARES)
Analyst Note:
The visible component is part of a Joint Direct Attack Munition (JDAM) guidance kit, an accessory package that is fitted to unguided air-delivered bombs to convert them to precision guided munitions. Specifically, this image shows a control fin from the tail assembly. Whilst the JDAM kit would not constitute a munition in its own right, this remnant is included in the OSMP as contextual information strongly suggests it formed part of a complete munition that functioned. (ARES)
2 Analyst Notes:
The JDAM-ER in this photograph is affixed to an unusual pylon thought to be of Ukrainian design, which allows the Western munition to be carried by the Soviet-designed Mikoyan MiG-29 and Sukhoi Su-27 fighter aircraft in service with the Ukrainian Air Force (a MiG-29 is pictured here). (ARES)
3 Analyst Notes:
This is an image released by the Israeli Defense Forces that shows an F-15I of 69 Squadron Israeli Air Force preparing to take part in a high-profile airstrike on 27 September 2024, in which the leader of Hezbollah, Hassan Nasrallah, was killed.
Analyst Note:
In this image, an F-15C fighter aircraft from 106 Squadron Israeli Air Force is seen carrying two MK 84-series 2,000-pound-class air-delivered bombs fitted with Joint Direct Attack Munition (JDAM) ‘bolt-on’ guidance kits. In U.S. service, this combination is known as the GBU-31. (ARES)
Analyst Note:
The Joint Direct Attack Munition – Extended Range (JDAM-ER) marries the JDAM guidance kit to a ‘glide bomb’ wing kit developed by the Australian Defence Force, offering a munition with at least three times the range of a standard GBU-38 500-pound-class guided aerial bomb. (ARES)
Analyst Note:
The SPICE family of munitions, manufactured by Israeli aerospace and defence company Rafael, includes two models which use ‘bolt-on’ guidance kits. The SPICE 1000 and SPICE 2000 models convert 1,000- and 2,000-pound unguided aerial bombs, respectively, to precision guided munitions. (ARES)
Analyst Note:
This component is one of four pneumatically controlled canards from the guidance section of a Paveway II precision guided munition (PGM) conversion kit. When a Paveway II conversion kit is fitted to a MK 82 series unguided air-delivered bomb (note markings), the munition receives a GBU-12 series designation. (ARES)