by which only aircraft capable of delivering precision-guided munitions (PGMs) would be allowed to bomb targets within the Baghdad metroplex. Downtown Baghdad was limited to weapons deliveries from F-117As and BGM-109 Tomahawk cruise missiles. As a result, while individual buildings and systems were demolished, the city of Baghdad was little touched by the campaign designed to help eject the Iraqis from Kuwait. This is the new face of airpower, where the right weapons are put on the right targets at the right time with the correctly planned weapons effects.
GENERAL PURPOSE BOMBS
History tells us that the first time aircraft were used to attack enemy forces on the ground was in January 1912, when an Italian second lieutenant named Giulio Gavotti, assigned to the
The basic family of GP bombs used by the U.S. military (including the U.S. Navy and U.S. Marine Corps) is known as the Mark (Mk) 80 series. Though some of the World War II-vintage Mk 117 (a 750lb./340.9kg. weapon) and Mk 118 (a 3,000 lb./1,363.6 kg. weapon) bombs are still in use on platforms such as the B-52, the standard family of weapons used on U.S. aircraft today are the 80-series GP bombs. Designed in the 1950s by the famous Ed Heinemann, the Mk 80 series are what is called low-drag, general purpose (LDGP) bombs. Previously, the designers of GP bombs which were carried internally, or on subsonic aircraft, gave little thought to how much parasitic drag they added to an aircraft in flight. This became a major issue, though, with the design of Heinemann's classic A-4 Skyhawk attack bomber, which carried all of its ordnance externally on pylons. Thus, he and his design team began with a clean sheet of paper, and came up with the LDGP shape so familiar to military enthusiasts around the world. The cases are made from cast steel, with relatively thin (less than 1 in./2.5 cm.) walls. This provides one of the bomb's primary damage mechanisms: fragmentation. Being relatively brittle, the steel case expands into a shower of fragments, deadly out to a certain radius. As for the explosive, the current generation of 80-series weapons uses an explosive called Tritonal 80/20. It is composed of an 80 % mix of TNT with 20 % of the volume of an aluminum binder/ inhibitor. The result is an explosive with slightly less explosive power than TNT but extremely stable in storage conditions such as ships and tropical sites. Also, it has a relatively high 'cook-off' temperature, which makes the 80-series bombs able to survive for a time in conditions of flame, such as a shipboard fire. Just for added insurance against a cook-off, the U.S. Navy coats their bombs with an ablative coating to buy extra time to suppress the fire and 'safe' the bombs.
About 50 % of the weight of an 80-series LDGP bomb is explosive, with the rest being taken up by the bomb case, mounting/attachment lugs, fin group, and fuze(s).
Fuzes are more important than you might think, since most modern explosives require a sequence of deliberate actions to detonate. Fuzes have evolved a great deal since the delicate glass/fulminate-of-mercury devices used in the American Civil War to detonate ground and naval mines. Today, you choose a specific fuze based upon how and when you want a weapon to blow up. The current generation of fuzes are notable because of the variety of conditions that they can be adapted to function in and their ever-increasing reliability. This issue of reliability is critical. If you lug a bomb into defended enemy airspace and drop it with pinpoint precision on an enemy target, and it does not explode because of a fuze failure, then you have just wasted fuel, time, and maybe a multi- million dollar aircraft (as well as your life) for nothing. Some of the more common fuzes include:
Another item critical to successful employment of bombs is making sure that bomb fragments do not hit the attacking aircraft. This can happen to an aircraft doing low-altitude drops with LDGP bombs in a 'slick' configuration. To avoid such accidents, 'hi-drag' kits were developed to slow the bomb down and provide enough separation for the launching aircraft to safely escape the effects of the weapons it has just delivered. In World War II, these kits took the form of an attached parachute. During the Vietnam War, the spring-loaded fins of the Mk 15 'Snakeye' kit were used on the Mk 82. Today, the standard hi-drag or retard kit is an air-inflated bag, or 'ballute,' mounted in a special fin-group assembly attached to the rear of the bomb. There are two varieties: the BSU-49/B for the Mk 82 and the BSU-50/B for the Mk 84. After launch, the ballute kits channel the slipstream surrounding the bomb into the ballute, inflating it from the incoming rush of air. Their big advantage is their vastly greater reliability over the Mk 15 units, as air moving at hundreds of knots/ kph. tends to be a more consistent mechanical medium than folded springs.
Penetration Bombs
A constant of warfare in the 20th century is that concrete has been one of the great equalizers among combatants. Cheap, available, and relatively easy to work with, it can be fashioned into a variety of structures which can protect even delicate, high-value items like aircraft and dictators from the ravages of the elements and the forces of modern warfare.
Ever since the end of the Vietnam War, the USAF wanted a bomb that could penetrate bunkers, runways, and other reinforced concrete structures — a bomb that didn't weigh 3,000 to 4,000 lb./1,363.6 to 1,818 kg., and wasn't nuclear. In 1984, the Air Force Armament Division initiated Project Have Void and awarded a contract to Lockheed Missile and Space's Austin (Texas) Division to develop the new bomb, to be known as the BLU-109/B. Forged out of hardened 4340 steel, the BLU-109/B is essentially a large 'masonry nail,' shaped to plow through concrete, earth, and armor plate, and then explode on the other side of the protection. Weighing in at 1,925.5lb./ 875.3 kg., it has a specially shaped nose that is designed to help it 'dig in' to flat concrete at high grazing angles. While the BLU-109/B can be dropped as a 'dumb' bomb, when married to a Paveway III-series or GBU-15 guidance kit, it becomes a killing machine of incredible power and accuracy.
With its capability of destroying, or 'holding at risk,' something like 99 % of all the hardened targets in the world, the BLU-109/B has transformed the nature of air warfare. Saddam Hussein found this out the hard way back in 1991, when these bombs blew up virtually every hardened target in his country. When the Iraqi Air Force tried to take refuge in Yugoslav- and European-built hardened aircraft shelters that were thought proof against even near- misses by tactical nuclear weapons, they were opened up like tin cans by the penetrating power of the BLU-109/B. After a couple of days of such pounding, the remnants of the Iraqi Air Force ran for Iran.
Cluster Bombs
Early in the Vietnam War, American airmen began to encounter more and more targets that were spread out — so-called 'area' targets made up of 'soft,' unarmored vehicles, supply dumps, and lightly built structures. What was needed was a weapon which would spread its effects over a known area, with a well-understood set of weapons effects. Rather than try to smear flaming napalm onto all of these things, something more modern was
