Looking Back

Sept. 11, 2008
SEPTEMBER 10, 1998
Joystick “feels real” in simulation games: The WingMan Force joystick from Logitech uses a cable-drive transmission that sends feedback to computer gamers. The drive, developed for aerospace, medical, and military simulations, lets users feel sensations, including engine rumbles, air turbulence, explosions, g forces, and oil slicks. To counter “push back” exerted against the user by the force-feedback technology, engineers at Bridge Design in San Francisco designed the device so one hand goes on the joystick while the other firmly holds the base. The stick contains an eight-way hat switch and thumb-controlled throttle wheel, while the base holds five programmable buttons.

Pratt & Whitney Aircraft has been selected to provide the engines for Boeing’s new generation of wide-body commercial jetliners, the medium-range 200-passenger 767. Two P&WA JT9D-7R high-bypass turbofan engines, developing 44,300 lb of takeoff thrust, will be installed on each 767 when it enters service in mid-1982. The JT9D-7R is the latest version of the JT9D engine, and is a rerated version of the JT9D-7, which produces 46,300lb of takeoff thrust and has been in service since 1971. The 7R’s lower thrust permits use of less-complex turbine hardware and retains a maximum number of parts common to existing JT9D-7 engines.

More speed on less power is the goal of a research program on underwater cargo vessels. A simple principle is involved: Submerged hulls don’t generate waves, thus have much less drag than surface vehicles. This jet-propelled model, conceived by Aerojet-General Corp. for the U. S. Maritime Commission, is controlled from a gondola atop a 100ft-tall strut. Air for the powerplant is drawn through the strut, snorkel-fashion. Underway, the ship operates with excess positive buoyancy. A triaxial-control system provides steering, longitudinal and transverse stabilization, and hydrodynamic control needed to force the ship to its proper operating depth. In effect, the craft flies underwater. The ultimate source for driving the jet-propulsion pumps is a nuclear powerplant.

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