Practice ordnance includes the BDU-50, a 500 lb. Air Force practice bomb. The BDU-50 bombs have a spotting charge that releases a cloud of smoke on impact. The Mk-82/BDU-50 500-pound and the BDU-56 [the inert version of the MK-84 2,000-pound bomb] are also used on some targets. These inert "heavyweight" bombs are dropped either with a parachute for "High Drag", or "Slick", which has no drag device. In either case, their weight creates enough "splash" or dirt spray, to be easily spotted without using an explosive charge. A new technique for the demilitarization and recycling of BDU-50 inert practice bombs involves using a contractor owned and operated plasma saw, eliminating the need for explosive venting.
Delivery of a BDU-50 High Drag Bomb from a low altitude, low dive angle results in the bomb impacting at or near the target and has very little or no ricochet, due to the aerodynamic effect of the high drag retard device. However, when the high drag system fails to deploy, the weapon takes on the characteristics of a low drag weapon and has a significantly increased slant range to impact (up to 4000 ft longer under certain conditions). This can be thought of as a range error (the aircraft was in the wrong place in the sky) for the delivery of a low drag weapon. Not only does it impact long of the target, but also it now has a lower impact angle and a higher impact velocity, which can result in a significant down range ricochet impact.
On 13 January 1999 Intercontinental Manufacturing Co., Garland, Texas, was awarded a $6,581,967 modification to a firm-fixed-price contract for 23,299 BDU-50 500-pound bomb bodies. Work will be performed in Garland, Texas, and was expected to be completed by Nov. 30, 2000. Contract funds will not expire at the end of the current fiscal year. This is a sole source contract initiated on Nov. 13, 1998. The contracting activity is the U.S. Army Armament, Munitions & Chemical Command, Rock Island, Ill. (DAAA09-98-C-0074).
The munitions to be loaded onto aircraft are brought to the flightline on a trailer. A jammer raises the BDU-50 bomb and it is locked into place by tightening some bolts. The BDU-50 is unloaded by loosening the bolts and using a missile loading device referenced as the MJ-1 or "jammer" to lift the bomb away from the aircraft. During the loading of one trailer holding 42 bombs, bombs are removed from the bunkers on seven bomb pallets (42 bombs) by forklift truck. The metal tie-down straps are cut and removed. The top pallet is removed. Plastic nose plugs are removed. Three bombs at a time are picked up by the forklift truck and are placed on the end of the 40-foot trailer. The bombs are manually rolled on wooden rails to the front of the trailer. Bombs weigh 465 pounds (lb) without fins. It takes seven pounds of force to roll a bomb on the rail. Fins are manually unloaded from fin boxes, attached to the back end of each bomb, and tightened in place using a pneumatic impact gun. Fins weigh 56 lb each. Metal nose plugs are attached and tightened using a wrench. The bombs are "locked down" using chains. The bomb building crew size is five. The employees informally rotate tasks.
Several hundred practice bombs are dropped each month by Air Force, Army, and Navy aviators at the Utah Test and Training Range (UTTR), located in western Utah. All bombs and munitions dropped at training ranges must be demilitarized, or "rendered non-recognizable as a bomb," before they can be disposed of or put to any other use. The current demilitarization (demil) process, performed by Hill AFB Explosive Ordnance Disposal (EOD) personnel, includes certifying that the bomb has been "fired" before placing it in large storage piles at the UTTR. The majority of the munitions dropped at the UTTR are 500 pound practice bombs filled with a mixture of concrete and vermiculite. Completion of the demil process requires cutting the inert bomb into pieces so it is no longer recognizable as a bomb.
The "fired" bombs at the UTTR, made of 1/2" thick steel, were estimated to represent approximately $1.2 million worth of recyclable, high-quality scrap metal if a safe, cost-effective way could be found to separate the metal bomb casings from the filler. In 1997, Hill AFB Environmental Management personnel decided to find a demil method that would turn this range residue from a liability into an asset. Any new demil method had to produce "clean" scrap metal at a rate of at least one ton per hour in order to be profitable. It was thought that the concrete filler should also be collected and recycled. After considering a variety of proposals and technologies, OO-ALC/EM staff built a portable machine that successfully cuts the bomb and separates the casing from the filler. The machine is able to produce clean scrap metal at more than the desired rate of one ton per hour.
The machine works by holding and rotating the bomb while a rotary saw blade cuts through only the thickness of the casing. Once the cut is completed, the bomb breaks in half and the filler can be easily removed from the casing by the same machine. Although the new demil and recycling process is still in the developmental stage, Hill AFB anticipates that the sale of the scrap metal will be profitable. A ton of clean scrap metal will sell for $55 to $120. The inert bombs will be properly demilitarized and recycled rather than transported to a landfill. The machine/process developed by Hill AFB is inexpensive ($9,000), has low maintenance requirements, and is safe to use. Hill AFB continues to refine the equipment to improve its efficiency.
|Join the GlobalSecurity.org mailing list|