MK80 series General Purpose Bombs

	MK82	MK83	MK84
Length:	7.2 ft (2.2 m)	9.8 ft (3 m)	12.5 ft (3.8 m)
Diameter:	10.75 in (273 mm)	13.8 in (350 mm)	18.1 in (460 mm)
Wingspan:	1.2 ft (0.38 m)	1.5 ft (0.48 m)	2.1 ft (0.64 m)
Weight:	500 lbs (227 kg)	1,000 lbs (454 kg)	2000 lbs (907 kg)
Explosive:	192 lbs (87 Kg)	440 lbs (200 kg)	948 lbs (430 kg)

CF-18 dropping Snakeyes in low drag modes

The MK (Mark) 80 series bombs have been around for decades, from the 50s to be more precice. The MK 80 series General Purpose Bombs are all similar in design other than their size. As seen in the table, the MK82 is roughtly 500 lbs and has two 14" suspension lugs (suspension devices engaging suspension hooks) to hang it off most type aircrafts. The MK83 is a 1,000 lbs version of the MK83 and it, also, has 14" suspension lugs. The MK84 is the bigger of the MK80 family and weighs approximately 2,000 lbs and is suspended by lugs that are 30 inches apart.

CF-104 releasing one Snakeye in high drag mode

The MK80 series GPBs (General Purpose Bombs) are basically a metal casing containing a nose and a tail fuze well (cavity), two suspension lugs (either 14- or 30-inches apart) and the explosive filling. The skin of the bomb varies in thickness varying from half inch to many inches getting thicker towards the nose to have some penetration abilities.

Different types of fin assemblies can be fitted on the bombs. They can be fitted with normal conical fins (seen in the cut-away picture below), retarding (high drag) fins, wing assemblies, and mine kits.

There are two main type of retarding fins, the MK15 Mod 4 and A.I.R. (Air Inflatable Retarder) as seen on the right. The retarding fins allows the delivering aircraft to execute low level high speed bombing and still escape the lethal envelope of the blast and fragmentation.

The MK82 with the MK15 Mod 4 fin assembly is nicknamed the "Snakeye" (seen on the picture on top of the page and on the left). When released in low drag mode, the fin assy (assembly) remains closed as seen on the CF-18 picture releasing 10 snakeyes. When released in high drag mode, the fin assy opens up like an ambrella as seen above and to the left effectively slowing it down. Upon bomb release a wire is pulled initiating a fin release band allowing the a spring on each of the fin to push the fins against the air stream which forces the fins back deploying them like an ambrella.

The Air Inflatable Retarder is a fin assembly which depending on the model fits all models of the MK80 serie GPBs. The three models used in the Canadian Air Force are BSU-49/B used on the MK82, the BSU-85/B used on the MK83 and the BSU-50/B used on the MK84. They contain two compartments: an empy space in the front half with an access panel giving access to a tail fuze and the portion to the rear which is the housing for the nylon retarder. when the bomb is released from the aircraft a lanyard unlatches the back cover which is allowed to swing open, in doing so it cause part of the nylon bag/retarder to come out and the air turbulence at the back of the bomb acts on that portion of the retarder that has been pulled out and pulls the remainder out of the housing, once out, the wind caused the the displacement of the bomb enters through four ram inlet and inflates the retarder. Its wide diameter creates a higher drag thus retarding the bomb.

Wing Assembly of a Laser Guided Bomb kit

The wing assemblies are fitted on the GPBs as part of a kit to adapt them as LGBs (Laser Guided Bombs) which provides them with lift to enable them to glide as long as possible to enable the GCS (Guidance Control Section) to acquire a target then dive on it.

The mine kits are installed on the bomb in order to use them as underwater mines, making the MK80 series a truly General Purpose Bomb family.

Cut away of a GPB with conical fins, M904 in nose and FMU-139 in tail fuze well

The fuze wells (either nose or tail) can be fitted with different types of fuzes. The fuzes are devices that keeps the bomb from going off while on the ground, along with providing a safe separation distance between the bomb and the aircraft on delivery by not allowing the bomb to arm until a preset delay has elapsed once the bomb has been released. The fuze also arms the bomb once the delay has ran its course. Arming the bomb which is the fuze's last function makes the bomb ready for detonation either on impact, shortly after impact or once a set condition has been met.

There are two types of fuzes currently in use in the Canadian Forces. The M904 mechanical fuze only used in the nose fuze well and the FMU-139 electronic fuze which can be used in either the nose or tail fuze well while in low-drag mode or in the tail fuze well only when in the high-drag mode (if equiped with the A.I.R.)

The Canadian military has had the MK82 for many decades in its inventory and has recently acquired the MK83 and MK84. If you have any questions on the MK80 series GPBs, send me an email and I'll see what I can do......

MK 80 Series General Purpose Bombs

MK 80 Series
General Purpose Bombs