How Boeing's Low-Cost Smart Bomb Revolutionised Strike Warfare

This year marks the 20th anniversary of the day in 1998 when Boeing delivered the first production model of the satellite-guided Joint Direct Attack Munition to the US Air Force. JDAM ("j-dam") was destined to transform the way in which the Air Force, Navy and Marine Corps conducted air strikes against ground targets, because it delivered pinpoint accuracy regardless of weather conditions.

Precision bombing had been a dream of aviators since the first bombers were built. If pilots could accurately attack key bottlenecks in an enemy's military apparatus and war economy, the adversary would be crippled and likely defeated. Unintended damage of civilian targets would be minimised. Precision bombing thus had the potential to be decisive, efficient and even humane compared to previous ways of waging war.

But hitting targets accurately turned out to be much harder in the early days than planners had expected. In one particularly disappointing episode during World War Two, 835 bomber sorties against a single Japanese factory produced only 4% damage while sacrificing 40 bombers. The inability to hit point targets in Europe and Japan led the Air Force, which was then part of the Army, to turn to indiscriminate area bombing of cities.

The advent of nuclear weapons made the newly independent Air Force first among equals in military councils after the war, but its leaders never gave up their dream of pinpoint accuracy that could minimise "collateral damage" in wartime. During the 1970s and 1980s, the necessary technology finally became available in the form of missile seekers that enabled munitions to home in on the image of a target or laser light reflected from an illuminator.

The first generation of precision-guided munitions, popularly known as smart bombs, were highly accurate -- if atmospheric conditions permitted them to be. However, as the Air Force and Navy discovered in Operation Desert Storm in 1991, when there was rain or dust or smoke around a target, seekers had trouble finding it. A smart bomb that could work regardless of weather conditions or local obscurants like smoke was needed.

That was the genesis of JDAM. Designers at Boeing devised an inexpensive way of providing free-fall gravity bombs with guidance from Global Positioning System satellites. Employing simple control surfaces and "strakes" along the side of the bombs that permitted them to glide, the Boeing technology converted "dumb" weapons into smart munitions. As long as the location of a target was known, JDAM could hit within a few yards of it even in a sandstorm.

The new system debuted in the Balkan air war of 1999, with stealthy B-2 bombers delivering 650 JDAMs against targets in Serbia during long flights from their home base in Missouri -- as chance would have it, the same state where Boeing manufactures the JDAM guidance package. Having already trained for years on a precursor to JDAM, Air Force pilots were able to hit 87% of intended targets in that initial air campaign.

That's remarkable performance in a place where poor weather conditions can degrade the performance of other types of smart weapons. JDAM quickly became the weapon of choice for US pilots, and warfighters in two dozen allied countries. Boeing would go on to produce hundreds of thousands of JDAM guidance packages for 500-pound, 1000-pound and 2000-pound bombs. Its plant in St. Charles, MO currently produces over a hundred per day in two shifts.

Today, all of the heavy bombers and strike fighters in America's joint force are equipped to deliver JDAMs, including the tri-service F-35. It's a safe bet the next-generation B-21 bomber will be too. Expectations for what strike warfare can accomplish have been genuinely transformed. Rather than sending half a dozen fighters to destroy one target, the military services can dispatch one fighter to destroy half a dozen targets -- in a single sortie, and at low cost.

Even with the price of the bomb itself included, a JDAM guidance system costs barely $30,000, whereas the value of the target it destroys with pinpoint accuracy may be over a hundred times that amount (or more). JDAM thus delivers an unusually favorable "cost-exchange" ratio to US warfighters, compared with weapons like cruise missiles that might cost the better part of a million dollars. And because glide weapons can be released miles from their targets, pilots are safer.

Smart weapons have been in the news lately, and not in a good way. Dozens of civilians in Yemen may have been killed by forces using a different type of American-supplied smart bomb. However, neither the makers of smart bombs nor their products are responsible for this tragedy. Precision-guided munitions enable pilots to tailor their strike tactics in order to minimise unnecessary damage, so in principle they can greatly reduce the number of innocent deaths in wartime.

It is up to the militaries employing them to use the technology in a responsible manner. War will never be a humane undertaking, but thousands of noncombatants are alive today in places like Afghanistan, Iraq and Serbia who might have been sacrificed if war had been waged the old way. Weapons like Boeing's Joint Direct Attack Munition have opened a new chapter in the history of strike warfare -- a chapter in which warring nations have fewer excuses for being inhumane.

Loren Thompson