Small Bomb Could Vastly Increase Strike Capability of U.S. Aircraft

By OTTO KREISHER
Special Correspondent

A small precision bomb being tested by the Pentagon holds out the promise that tactical aircraft of the near future will be able strike three to four times the number of targets assigned to U.S. planes operating over Iraq today. The bomb’s small size and precision would vastly improve the attack capability of U.S. aircraft simply by increasing the arsenal that could be sent aloft.

The Small Diameter Bomb (SDB), a 250-pound weapon with fold-out wings and advanced, jam-resistant, Global Positioning System-Inertial Navigation System (GPS-INS) guidance, will give a fighter or bomber unprecedented levels of precision attack capability and stand-off protection. It is half the weight of the smallest bomb used today, the 500-pound Mark 82.

Armed with a full load of these small weapons, a tactical aircraft would be able to attack more than a dozen targets and an Air Force B-1 bomber up to 96, hitting them from more than 40 miles away and with less risk of collateral damage to nearby structures or people. Increased accuracy and smaller blast will make the 71-inch-long bomb an ideal weapon for urban warfare, program officials said.

According to Air Force statistics, as of June 2003 the service maintained an inventory of more than 1,500 tactical aircraft in its active-duty force and 60 B-1 bombers. Each tactical airplane typically carries four bombs, while the B-1 can be armed with up to 24 Joint Direct-Attack Munitions (JDAMs), 2,000-pound munitions widely used in Iraq and Afghanistan.

Being developed by Boeing under an August 2003 contract, SDB systems are expected to become operational with Air Force squadrons in early 2006. Navy and Marine Corps squadrons could start receiving a more advanced version of the bomb by the end of the decade.

The SDB also is intended for use by the joint unmanned combat aerial vehicle being developed by Boeing and Northrop Grumman.

Rep. Duncan Hunter, R-Calif., chairman of the House Armed Services Committee, called these small precision weapons “the wave of the future.”

“I think the idea of leveraging our stealth aircraft combined with precision munitions is one of America’s great advantages,” Hunter said.

In addition to being able to carry a lot more weapons on each aircraft, it is more efficient “if you can take out a target with a Small Diameter Bomb that otherwise would take a JDAM,” Hunter said.

Boeing won a $188 million development contract for the small bomb system Aug. 28, 2003, after a two-year concept demonstration competition with Lockheed Martin.

The contract covers a lot more than just the bomb, designated the GBU-39B. It also requires Boeing to produce a computer-equipped “smart bomb carriage,” the BRU-61A, that enables an aircraft to carry and manage four SDBs on each standard weapons station; the Accuracy Support Infrastructure, which corrects GPS data to produce unrivaled accuracy, and the necessary logistical and support material, including mission-planning software.

The bomb, the carriage and the accuracy support system are based on more than a decade of Boeing development work, including the guidance unit that turns dumb bombs into precision JDAMs.

The bomb has an adjustable fuse, which allows the aircrew to order it to explode above ground, on contact or with a delay that will enable it to penetrate hardened targets.

Although much of the SDB system relies on existing technologies, program officials said the big challenge is the accelerated schedule.

The time line “is as aggressive [as], if not more aggressive [than], any weapon program I’ve seen,” said Air Force Col. James McClendon, SDB program manager at Eglin Air Force Base, Fla.

The system is expected to get Defense Acquisition Board (DAB) approval for low-rate production next spring and be operational with F-15E squadrons a year later. It then will be added to most of the Air Force’s other strike aircraft. The DAB is the Pentagon’s top acquisition panel headed by Michael Wynne, the undersecretary of defense for acquisition, technology and logistics.

But the priority, McClendon said, is to match the small munitions with the stealthy F/A-22 strike fighter, now in operational evaluation. The F-15 deployment will be used to test and “mature” the system, he said.

The initial contract calls for 24,000 bombs, 2,000 bomb carriages and the associated support gear, at an estimated total price of $2.5 billion.

Boeing conducted a test drop of a single bomb from the smart carriage on an F-15E on April 22, said Dan Jaspering, Boeing’s SDB program manager. The company will conduct a “ripple release” of four bombs in the future before the DAB, he said.

About the time the GPS-INS guided bombs become operational, Boeing expects to get funding to step up development of an SDB with an active seeker warhead and target recognition capability. That would make the weapon effective against moving targets, Jaspering and McClendon said.

The Navy is working with the Air Force on the requirements for that weapon and is expected to share development and production cost, the officials said.