Defense Advanced Research Projects AgencyTagged Content List

Transformative Materials

Relating to new or improved properties in materials

Showing 16 results for Materials + History RSS
In the early days of DARPA’s work on stealth technology, Have Blue, a prototype of what would become the F-117A, first flew successfully in 1977. The success of the F-117A program marked the beginning of the stealth revolution, which has had enormous benefits for national security.
DARPA established the Defense Sciences Office (DSO) in 1980, combining the Nuclear Monitoring Research Office, materials science research, and cybernetic technology efforts into a single office. Since its inception, DSO has spawned two additional technology offices at DARPA: the Microsystems Technology Office (MTO) in 1992 and the Biological Technologies Office (BTO) in 2014.
Between 1968 and 1972, ARPA supported an effort proposed by the University of Denver to use explosives for forming metal parts for aerospace applications. The underwater process relied on a mold for the part over which was placed a plate of the metal alloy to be used. This preparation, when immersed in water, would feel the shock of an explosive charge to such a degree that the metal plate would be forced against the die. The process could reproducibly deliver serviceable parts out of steel, aluminum, titanium, and Inconel, a superalloy. The effort opened a new way to produce a variety made of aerospace components, including engine parts such as engine diffusers and afterburner rings for Pratt &Whitney engines that powered the storied SR71. The variation of the process also was deployed for many years to weld superstructures to the decks of U.S. Navy warships.
Beginning in the mid-1970s, DARPA orchestrated extensive research into the semiconductor material gallium arsenide, which could host faster transistors operating at higher power than could silicon. The work would contribute to subsequent DARPA-spurred achievement in the 1980s to miniaturize receivers for GPS. That technology, in conjunction with DARPA-developed advances in inertial navigation, expanded the Nation’s arsenal of precision-guided munitions (PGMs) through such innovations as “bolt-on” Joint Direct Attack Munitions (JDAM) GPS kits, which gave otherwise unguided or laser-guided munitions new, high-precision capabilities. Key to these developments were gallium arsenide chips developed through DARPA’s Monolithic Microwave Integrated Circuit program, which also enabled the radio frequency (RF) and millimeter-wave circuits needed in precision weapons.

In the early 1970s, a DARPA study brought to light the extent of vulnerabilities of U.S. aircraft and their on-board equipment to detection and attack by adversaries, who were deploying new advanced air-defense missile systems. These systems integrated radar-guided surface-to-air missiles (SAMs) and air-launched radar-guided missiles, all networked with early-warning, acquisition, and targeting radars, and coordinated within sophisticated command and control frameworks.

To mitigate these growing threats, DARPA embarked on a program to develop strategies and technologies for reducing radar detectability, including the reduction of radar cross section through a combination of shaping (to minimize the number of radar return spikes) and radar absorbent materials; infrared shielding, exhaust cooling and shaping, and enhanced heat dissipation; reduced visual signatures; active signature cancellation; inlet shielding; and windshield coatings.

In the mid-1970s, DARPA oversaw the development of HAVE Blue, the first practical combat stealth aircraft, which made its first test flight by the end of 1977. This led to the procurement by the Air Force of the F-117A stealth fighter, which became operational in October 1983. A follow-on development, the TACIT Blue aircraft, could operate radar sensors while maintaining its own low radar cross-section. This laid foundations for development of the B-2 stealth bomber.

Stealth aircraft destroyed key targets in conflicts in Iraq, both in the 1991 Desert Storm operation and in 2003 during Operation Iraqi Freedom; in Afghanistan during Operation Enduring Freedom in 2001; and in Libya in 2011. Complementing the key contributions of stealth capabilities in these missions was Department of Defense’s use of other technologies, including DARPA-enabled precision-guided munitions, which were deployed by stealth and non-stealth aircraft. Since their initial development and deployment, stealth technologies have been applied to a wide range of weapon systems and military platforms, among them missiles, helicopters, ground vehicles and ships.