While for many years the upper echelon of the aviation community has enjoyed the benefits of high-tech devices, general aviation has been slow to adopt the now ubiquitous computer into their cockpits. With the advent of the personal computer, cockpit implementation of the small computer is now both economically feasible and practical.
This article examines the installation and use of a small home computer, the Timex/Sinclair 1000, as a pilot aid in the cockpit. The T/S 1000 was chosen as a likely computer to install for several key reasons. It is compact, light, readily available for under $50 and requires only a single voltage for operation. Figure i shows a simple schematic diagram that will allow the computer to be installed on board. A complete installation package for under $40 is available from Practiputing, Р.О. Box 44167, Tacoma, WA 98444.
This kit includes all necessary filters, regulators and connectors.
The monitor used to display the information can be as simple as a portable black and white television set. The prototype system installed in this author’s Cessna 152 uses а 5-inch diagonal television installed at a distance of 30 inches.
Shielded cable was used in all installation wiring and in over 56 hours of use no interference between standard avionics and the onboard computer has been noted.
As software becomes more intelligent, the hardware implementation of the computer will spread to many areas. With proper transducers, engine and aircraft parameters can be constantly monitored, with alarms sounding only when out of range conditions exist. These readings can include such vitals as oil temp, oil pressure, airspeed, rate of climb, roll rate, angle of attack (stall indicator), cylinder head and exhaust temperatures, fuel flow and level, crab angle and magnetic heading, to name but a few.
Does this sound similar to the Boeing 757 Avionics package?
Another area where the computer can shine is in an Area Navigation System. When properly programmed into the computer, this system aids the pilot in gathering information, calculating position and; by using the trigonometric functions on Cartesian coordinate points, can direct the pilot on a heading to his destination, correcting for winds and magnetic variation. The computer will also display time to destination, fuel status, alternate airport course computation, groundspeed and other items of interest to the pilot.
Before flight, the computer prompts you for flight information on your aircraft and destination. This includes things like beginning fuel amount, fuel burn rate, beginning and end points in the flight, and magnetic variation over the intended route.
The Area Navigation Program is menu driven so that all the user must do is select the number that corresponds to the desired function and press а single number between one and nine. All data entered into the computer is numeric and can be entered via an optional 10-key keypad strapped to the pilot’s knee.
The beauty of the installed system is that the computer prompts you for all inputs. The user does not need to memorize sequences of numeric entry or cryptic codes in order to reap the benefits of the silicon age. (And all this for under $250, including computer, monitor, and software.)