10 YEARS AGO — 2000
Composites put muscle in prosthetic arm: The outer covering and exoskeleton of a high-tech prosthetic arm called the Utah Arm 2 must protect internal components and support loads of over 50 lb. Thermocomp RC, a carbon-fiber-reinforced nylon 6/6 from LNP Engineering Plastics, Exton, Pa., provides the tensile strength for the exoskeleton, the structure that supports the greatest loads. Developers at Salt Lake City-based Motion Control then used Thermocomp QF, a glass-fiber-reinforced nylon 6/10 for the lower forearm and hand covering. QF absorbs little moisture, can be easily colored, and withstand the wear and tear of normal life.

30 YEARS AGO — 1980
Window to the sea: A craftsman at BF Goodrich Co. is shown putting finishing touches on the first of 43 sonar domes slated to be mounted amidships beneath the keels on the
Navy’s new Oliver Hazard Perry-class frigates. The 23-ft-long rubber domes will act as windows for transmitting sonar signals.

50 YEARS AGO — 1960
Fastest thing on three legs: The most advanced hydrofoil in existence made its first public appearance at a demonstration by the U. S. Navy. The XCH-6, which is the first craft to be fitted with supercavitating hydrofoils and propeller, exceeded 70 mph at an international symposium on hydrodynamics in Holland. The 23-ft vessel, designed by Dynamic Developments Div. of Grumman Aircraft Engineering Corp., is powered by a GE T-58 turbine engine rated at 1,050 shaft hp.