Binary fuels can be safely stored and utilized safely according to the patents as has been repeatedly posted.
Lightweight 155 mm Liquid-Propellant Naval Gun Mount. In 1993, Martin Marietta announced a lightweight 155 mm liquid-propellant naval gun mount for this advanced gun program. It hopes to reach a range of 45 nautical miles with existing ammunition, and to exceed 100 miles with new projectiles, a rate of fire of 11 to 16 rounds per minute, and a velocity accuracy of better than 0.25 percent. It should then be able to fire a 4- to 8-round simultaneous impact mission at 6 to 40 kilometers. Range is increased because there is a capability to precisely inject propellant throughout the combustion process. The system offers soft launch with reduced chamber pressure, and ammunition storage volume is reduced because there are no cartridge cases. Martin Marietta estimates that this 155 mm L52 will weigh 40,000 pounds (compared to 110,000 lb for an 8-inch L55), and will achieve a range of 54,000 yards. Elevation limits are +65 to -15 degrees; rate of fire is 16 to 29 rounds per minute with 60 ready-use rounds. This development has since been at least partly overtaken by the introduction of the L62 barrel on the Mk 45 gun with the capability of firing extended range guided munitions (ERGM). The combination of extended barrel and non-ballistic guided munition will extend the gun’s coverage to about 60 miles (100+ km). Meanwhile, a new 155 mm gun mount is being developed (as a derivative from the USMC 155 mm unit); the DD(X) class will presumably be the first platform to adopt it.
Background. In 1987, FMC (now part of United Defense) announced the development of its combustion-augmented plasma (CAP) technology for advanced gun development. Two major fields of exploitation were envisaged: long-range fire support for shore operations and close-range anti-missile defense. In the 1987 announcement, FMC showed its version of CIWS-2000, which used CAP and carried two rather than six barrels. The first experiments used 10 mm projectiles. Later, 30 mm were used, and FMC expected to fire 90 mm projectiles. All of these experiments used liquid propellants, although a conventional solid propellant might also be used. In 1987, FMC applied its CAP technology to an Air Force funded hypervelocity ammunition technology (HAT) program in which a sideways-pointing anti-tank gun was to be mounted onboard a C-130 or successor gunship that would fly just behind the battle line. CAP was also proposed as part of a hybrid rail gun for anti-missile defense, to be used to inject a projectile into the electric gun. FMC patented its CAP concept in 1985, and in 1990 it began a CAP naval gun project under the US Navy’s Balanced Technology Initiative. The weapon developed under this program is designated the electrothermal gun, and is considered a much nearerterm proposition (e.g., for point defense) than a full electric gun. Compared to alternative exotic guns, CAP can use a conventional barrel and projectiles. FMC claims that CAP offers better reliability and internal ballistics control than a liquid-propellant gun. In late 1990, the US Navy acknowledged the need for a new-generation close-in defense system to combat the latest anti-ship missiles. The use of electrothermal gun technology promised a new weapon that would use the same trunnion that housed the Phalanx system but offer significantly increased performance. Design work commenced in the last quarter of 1990, and was to be completed in the last quarter of 1991. A 31-month design contract valued at US$4.6 million was awarded to FMC for development of the new weapon in November 1990. The FMC 60 mm electrothermal gun and its Martin Marietta (formerly GE) guided round small-caliber smart munition (SCSM) were tested successfully during 1992/93. The SCSM contract was awarded in the autumn of 1991. The 1.75 kilogram rolling-airframe steel shell (illustrated in this report) uses a K-band guidance uplink and an E/F-band telemetry downlink. It carries a thermal battery and a miniature propulsion Electrothermal (ET) Gun, control using a small solid-propellant thruster. Muzzle velocity is 1.4 kilometers per second (4,260 ft/sec); SCSM can maneuver at 40g at Mach 4. Like Phalanx, this weapon kills by impact, not by explosion. Of the seven saboted projectiles successfully fired at Dahlgren Naval Base in the second half of 1992, five carried live gas generators and thermal batteries. The K-band command link was tested over water at Dahlgren in February 1993. Tests against airborne targets were scheduled for late 1994. The gun is an autoloader on a Phalanx mounting. Firing rate is 4 rounds per second/10 round burst); elevation limits are +40/-5 degrees. Following a 30-month design and development program, the first 60 mm ET gun was delivered to the US Navy in July 1993. Following the completion of final NSWC acceptance trials, the gun, autoloader and other program elements – including propellant charges, guided projectiles and the TASD target acquisition system – will be integrated during a series of live firings against airborne targets. In December 1994, the US Navy announced that it expected to make a decision on the feasibility of using electrothermal gun technology for future naval weapons by 1998. The studies, costing some US$107 million, would determine if a 155 mm electrothermal gun would provide a feasible, practical, and affordable solution for the US Navy’s naval surface fire-support requirements. The study program would use a 5-inch L54 Mk 45 mount as a design baseline to evaluate the technology issues involved. The objective is to increase the gun range from its existing 27 kilometers to a maximum of 150 kilometers, and to integrate this improved performance with a new guided round. However, by mid-1996, the whole US Navy side of this program was strongly de-emphasized in favor of the Army-related aspects. No work was being carried out on the naval weapons and no early introduction to service was predicted by company officials. The performance increments gained by the introduction of combustion-augmented plasma technology are evolutionary rather than revolutionary, but, combined with the development of practical guided projectiles, are sufficient to restore a substantial measure of credibility to gun-based CIWS. The application of CAP technology to basic conventional gun designs means that the 60 mm ET-gun technology demonstrator should be adaptable to a service weapon within the forecast period. The timing of such a program will be determined by funding constraints. At present, other priorities are considered more pressing.
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