penetrator bomb that was used on the last night of Desert Storm. Officially designated as the GBU-28/B. Its origins date back to August 1990, when the first planning for an offensive air campaign against Iraq began. As the planners in what was known as the Black Hole began to look at strategic targets around Baghdad, they noted a series of super-hard command and control (C) bunkers, so heavily built that there were doubts about the ability of the BLU- 109/B warhead to penetrate and destroy them. With this in mind, a request was made to study the problem at the USAF Air Armament Division at Eglin AFB, Florida. Down at Eglin AFB, a quiet study was started to look over the problems associated with an improved penetrating bomb. In the study group, headed by Major Richard Wright, there was an engineer named Al Weimorts, who began to make some early sketches of a concept bomb that might just do the job. And that was where the idea stayed until the early BDA results from Desert Storm began to come in. By January 21st, 1991, it was clear that the BLU-109/ B-equipped LGBs were just not getting the job done. All they had done to the big bunkers was scab the surface, and not much else. Worse, with more and more of the other Iraqi C bunkers being destroyed, a greater percentage of the top Iraqi leadership was taking refuge in the big command bunkers and continuing operations. This made the destruction of those bunkers a top priority, and the word went out to the team down at Eglin to find a way to do so quickly.
Given their marching orders, TI, as well as the BLU-109/B team at Lockheed, got to work on a number of different problems at once. First there was the problem of the warhead. While the basic design of the BLU-109/B was sound, what was needed was something larger — longer and heavier, with a larger explosive payload. Also, because they had to bolt a modified Paveway III kit onto it, and because they had to maintain the necessary clearance to fly and drop it from either an F-111F or F-15E, it would
Next, to machine and finish a forged-steel blank would take months, and the Eglin team had days. Luckily, an engineer at the Lockheed plant where the BLU-109/Bs were made was a retired U.S. Army trooper who remembered a stock of old 8-inch/203mm howitzer gun barrels lying around (literally) at the Letterkenny Arsenal in Pennsylvania. Made of the same kind of hardened steel as the BLU-109/B, they had been happily rusting away for some time. By February 1st, 1991, a number of the old gun barrels were shipped to the Watervliet Army Arsenal in upstate New York and machined into the shape of what would become known as the BLU-113/B Super Penetrator. Eventually, around thirty-two of the BLU-113/Bs would be built for integration into what was going to be known as the GBU-28/B. Several inert (non-explosive) tests indicated that the new bomb was capable of doing the job. This included one test on a rocket sled at Holloman AFB, New Mexico, where it penetrated 22 feet/6.7 meters of reinforced structural concrete, and then continued on to careen downrange for another mile or so without any damage whatsoever to the BLU-113/B. Each of the new warheads eventually weighed in at 4,700 lb./2,136.4 kg., and had to be hand-loaded with some 1,200 lb./545.45 kg. of explosive, and then integrated with the guidance kits from TI.
Those guidance kits were a whole story on their own. Meanwhile, the original Paveway III development team had long since moved onto other jobs within TI, and had to be reconstituted as quickly as possible. Murl Culp from Lockheed contacted TI and discussed the feasibility of guiding the new penetrator with a derivative Paveway III GCU. Luckily, Bob Peterson, an original Paveway III engineer, was still with the company, and was able to reassemble enough of the original team to get the ball rolling. And other members of the team were pulled off of other important TI programs to staff the effort. By February 12th, the TI/Lockheed team was down at Eglin AFB briefing guidance concepts to the Air Force.
Once the new guidance software was completed, the major testing normally associated with development of a new Paveway GCU would have to be accomplished in days rather than years. A key problem was access to the only wind tunnel in the Dallas/Fort Worth area capable of doing the testing required to develop and validate the new LGB's software. Owned then by LTV/Vought, it was heavily booked with projects, and the security around the GBU-28/B precluded doing anything special to 'force' the owners to provide access for TI. Thus, TI would have to use the only open 'window' on the tunnel's calendar, on the weekend of February 16/17, just four days away. Now, it should be remembered that at the time all of this was going on, TI, Lockheed, and the Air Force did not have any sort of contract for this project. What they did was done on a handshake and good faith, and TI decided to trust in that when they scheduled the tunnel time. They constructed a 1/4 subscale model to establish the ballistics of the new BLU-113/B/Paveway III combination, which was designated the GBU-28/B.
The tunnel testing was completed by the early hours of Monday, February 18th, and the effort now fell completely on the shoulders of the TI team. Over the next week or so, they worked around the clock to produce the software that would allow the bomb to guide successfully to a target. Almost as an afterthought, the Air Force called with an order for the first two guidance kits on the 19th, and the GBU-28/B was finally an official project, financially and contractually. Two days later, on the 21st, a TI-chartered aircraft loaded with four large airfoil groups took off from Love Field in Dallas, bound for Eglin AFB. These would be part of the actual kits that would be shipped to the Taif RSAFB, where the 48th TFW was based. The decision had been made that the F-111F would deliver the new bombs, mainly because the airframe was more mature than that of the F-15E.
On February 22nd, TI was asked to produce two more of the GBU-28/B guidance kits and ship them ASAP out to Nellis AFB, Nevada. The Air Force wanted to do a full-up test of the new bomb being dropped from an F-111F before it went to combat over Iraq. The ground war into Iraq and Kuwait was only hours from starting, and the Air Force wanted to be sure the system worked.
On the morning of February 24th, the final test of the new bomb took place. A fully integrated bomb (with an inert warhead; the explosive charge was not loaded) was dropped by an F-111F at a target on the Nellis AFB range. The results were stunning. Not only did the GBU-28/B hit the target as advertised, but it dug a hole over 100 feet/30.5 meters deep in desert caliche (hard clay soil with roughly the same consistency as concrete!). The BLU- 113/B-equipped LGB was buried so deep, it could not be retrieved. It remains there to this day.
After the single 'event' (as tests are sometimes called), TI programmed two GBU-28 GCUs (designated WSU-36A/B), and flew them out to Eglin AFB on Monday, February 25th. These were mated with two of the previously shipped airfoil groups, strapped to a pallet along with a pair of BLU- 113/B warheads, loaded aboard a USAF C-141B StarLifter, and flown to Taif RSAFB on February 27th. Since the normal BSU-84/B planar wing section was too big to allow the proper ground clearance and separation from the F-111F, and a gliding bomb was not really required (the GBU-28/B was to be dropped from high altitude), a modified version of the GBU-27/B tail fin assembly was developed for attachment to the new bomb. Covered with signatures and messages from everyone who had handled them during the program, they were two of the oddest-looking weapons ever built.
Within five hours of landing at Taif, the two bombs were loaded aboard a pair of 48th TFW F-111Fs, and their crews were briefed to hit a very special target that very night. For some time, a bunker known as Taji #2 had been monitored closely by elements of the U.S. intelligence community. Located at the al-Taji Airbase, approximately 15 nm./27.4 km. northwest of Baghdad, it had been hit no less than three times by F-117As with GBU-27/Bs early in the war. In the words of General Horner, they only 'dug up the rose garden.' Since that time, various estimates had suggested that the top national command authorities of Iraq, including possibly Saddam Hussein himself, were running the war from this bunker. With less than twelve hours left before the planned cease- fire, scheduled for 0800 Local Time (0500 Zulu) the next morning (February 28th), CENTAF was ordered to hit the bunker with the bombs. Each F-111F was loaded with a GBU-28/B under one wing and a single 2,000 lb./909.1 kg. GBU-24A/B under the other, for balance. Even so, while they taxied to takeoff position, the F-111s 'leaned' to one side because of the weight imbalance.
On the night of February 27th/28th, 1991, the two F-111Fs took off and headed north towards the airfield northwest of Baghdad. The aircraft made their runs and dropped their bombs. They aimed for an air shaft on the top of the bunker, and at least one of the bombs hit its target. Penetrating the thick, reinforced concrete, it detonated in the heart of the bunker. The results were horrific. All six of the bunker's armored blast doors were blown off their hinges; then a huge glut of flame and debris swelled up. Anyone inside was clearly dead, though to this day we do not know who was there. Though they have never been confirmed, postwar rumors claim that a number of senior
