Joint Direct Attack Munition Research Articles

A Firepower Assignment Method for Barragging the JDAM

In this paper, the development of Joint Direct Attack Munition (JDAM) and the importance of firepower assignment are introduced, as well as the analysis on the bombing ways of JDAM. Consider the target threat level and comprehensive favorability about the targets distribution problem when taking barrage firing method to JDAM. It gets the optimal distribution of shooting based on example and data.

Arterial Missile Embolus Resulting from a Novel Mechanism: A Case Report.

Missile emboli from bullets occur infrequently, with the first reported case appearing in 18341. At least 160 reports of this phenomenon exist in the literature2. A variety of missile emboli, including arterioarterial as well as aortoarterial emboli, have been reported, with up to two-thirds causing peripheral ischemia3. The patient discussed in this case report initially had no symptoms in the affected right extremity. This may be common; less than one-third of missile emboli initially are symptomatic3. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A forty-year-old U.S. soldier was performing combat operations in Afghanistan when a 2000-pound Joint Direct Attack Munition aerial fragmentation bomb impacted approximately 100 yards away from his position. He sustained multiple fragment wounds to the left leg, the left flank and back, and the right wrist and hand. He was initially stable and was evacuated from Afghanistan to Seeb Air Base Hospital in Oman, with a transport time of approximately six hours. The only prehospital treatment he received was placement of an intravenous line (IV) in the right antecubital fossa. Upon arrival at the hospital, the only symptom was right upper-extremity pain from the elbow distally, which had started after the IV had been placed. On physical examination, he had spontaneous air entry with diminished breath sounds on the left side. There were multiple wounds smaller than 5 mm over the left leg, left flank and back, and the right wrist and hand. There was a sizeable wound approximately 1 cm in diameter on the left posterior thorax (Fig. 1). All limbs were perfused with brisk …

Recent results in robust adaptive flight control systems

SUMMARYAdaptive control has been increasingly used in flight control of late, with notable technology transitions to autonomous flight platforms such as Joint Direct Attack Munition (JDAM), X–36 Tailless Fighter Agility Research Aircraft, NASA Generic Transport Model (GTM), and Boeing Phantom Ray. Given the need to make these flight systems autonomous, the spotlight, more than ever, is firmly on adaptive control and in particular, robust adaptive control systems. In this paper, we present a few recent results in robust Adaptive Flight Control Systems (AFCS) that showcase the advantages, properties, and performance of AFCS, whose foundations were laid more than 50 years ago. Copyright © 2012 John Wiley & Sons, Ltd.

Modeling of Underwater Bomb Trajectory for Mine Clearance

The falling of a Joint Direct Attack Munition (JDAM) through a water column was modeled using a six degrees of freedom model (called STRIKE35), which contains three components: hydrodynamics, semi-empirical determination of the drag/ lift/torque coefficients (depending on the Reynolds number and the angle of attack), and water surface characteristics.To validate and verify this model, three underwater bomb trajectory tests were conducted in the Naval Air Warfare Center, Weapons Division (NAWC/WD) in the middle of Indian Wells Valley, California. During the test, several JDAMs were dropped from an airplane into two frustum ponds with the same bottom diameter of approximately 30.5 m, different surface diameters (61 m, 79 m), and different depths (7.6 m, 12.1 m). High-speed digital cameras with light/pressure sensors, and a global positioning system were used to record the location and orientation of JDAMs. Model—data inter comparison shows the capability of STRIKE35, which may lead to a new approach (breaching technology) of sea mine clearance in very shallow water (water depth less than 12.2 m, i.e. 40 ft).

9.3.1 A Vector Approach to Assessing Modularity

AbstractA method to assess product modularity using a vector approach is presented and demonstrated using two precision guided munitions. Modularity has several fundamental benefits agreed upon by industry including reusability, flexibility, reconfigurability and extensibility. Current modularity measures focus on interfaces within or between modules in provide/depend relationships. A new method that assesses the module interfaces as well as captures and addresses each of the recognized modularity benefits is presented in a Vector Modularity Measure (VMM). Components of the VMM include terms for degree of coupling, reusability, and flexibility. Flexibility is assessed in terms of reconfigurability and extensibility. The overall evaluation method is then summarized, followed by an application using two similar precision guided munitions in the U.S. Air Force inventory: the Guided Bomb Unit‐24 (GBU‐24), referred to as the laser guided bomb (LGB); and the Guided Bomb Unit‐31 (GBU‐31), referred to as the Joint Direct Attack Munition (JDAM).

Arms and Innovation: Entrepreneurship and Alliances in the Twenty-First Century Defense Industry (review)

Reviewed by: Arms and Innovation: Entrepreneurship and Alliances in the Twenty-First Century Defense Industry Byron K. Callan Arms and Innovation: Entrepreneurship and Alliances in the Twenty-First Century Defense Industry. By James Hasik. Chicago: University of Chicago Press, 2008. ISBN 978-0-226-31886-8. Tables. Notes. Index. Pp. 189. $35.00. Small business firms have played an important role in the development of contemporary weapons systems and technologies. This is particularly true of sectors where there has been rapid technological change, such as the aircraft industry in the first part of the last century and more recently in defense information technologies. But even in seemingly mature markets, small firms can play critical roles engendering major military innovation. For example, Higgins Industries of New Orleans developed the Eureka workboat in the late 1920s and early 1930s. The Eureka was ideally suited for the bayous and swamps of Louisiana where it was initially used in logging operations. In 1939, Higgins received a contract from the Navy for an experimental landing craft based on the Eureka and subsequent designs were critical to the conduct and execution of U.S amphibious operations in the Second World War. [End Page 1028] James Hasik's Arms and Innovationhas a contemporary focus, but provides a useful framework for historians to consider the structure and evolution of defense industries, and the role of small enterprises in developing weapons and supporting products. Hasik uses six case studies of current or recent U.S. defense procurements to discuss the role of small firms in the arms industry. These vignettes on weapons such as the Predator unmanned air vehicle, the Joint Direct Attack Munition, and the Space-Based Infrared Sensor are used to illustrate why small firms succeeded, or were unsuccessful, in developing and producing defense products. The case studies are well chosen as they include commercial products adopted for military use, and purpose-built weapons and software products Hasik identifies three circumstances where small firms could be "relatively advantaged" over larger enterprises. The first is "innovative" markets that don't require capital-intensive research and development and for which the vector of technological change is uncertain. Another is in circumstances where a high degree of skill is needed but where ensuing production runs could be low. The third is where there are already large players but where there is room for smaller firms to prosper. He also discusses circumstances where small companies should consider an alliance with larger enterprises. The audiences Hasik directs his recommendations to are aspiring and current defense contractors both large and small and government procurement and policy personnel. Hasik does not believe that small firms hold all the keys to weapons innovation and indeed the purpose of his study of the Joint Direct Attack Munition is to highlight instances where a small firm was not as well equipped as a large one (in this case Boeing) to undertake high level serial production of a weapon. However, he believes "small firms have an important role to play in the cycles of military-industrial development…" There were some areas that Hasik could have been explored in greater detail. Little was said about how small firms were able to make their skills and products initially known to potential military customers. In some instances, the U.S. Congress has played a critical role in shepherding and protecting smaller firms and this could have been discussed, particularly in the instance of the Predator program. And inter-service rivalries can also help a smaller firm find willing new customers. Little was said about the funding and policy initiatives that could provide entrance points for smaller innovative firms in defense markets. However, Arms and Innovationdeserves a place in the library of anyone interested in military procurement and weapons development. For the historian, the framework Hasik used may be helpful in identifying the circumstances in earlier time periods that allowed smaller firms and enterprises to bring forth new military tools. [End Page 1029] Byron K. Callan Darien, Connecticut Copyright © 2009 The Society for Military History

Simulations of Store Separation from an F/A-18 with a Cartesian Method

Coupled computational fluid dynamics with six-degree-of-freedom trajectory predictions using an automated Cartesian method are demonstrated by simulating a GBU-31/Joint Direct Attack Munition store separating from an F/A-18C aircraft. Numerical simulations are performed at two Mach numbers near the sonic speed and compared with flight-test telemetry and photographic-derived data. For both Mach numbers, simulation results using a sequential-static series of flow solutions are contrasted with results using a time-dependent approach. Both numerical approaches show good agreement with the flight-test data through the first 0.25 s of the trajectory. At later times the sequential-static and time-dependent methods diverge, after the store produces peak angular rates; however, both remain close to the flight-test trajectory