Tune Machine The Rnav Running Computer-aided System Developed

As the performance limitation of earlier B737, the traditional route of China civil aviation ferry flight from South Pacific was Hawaii-Marshall Islands-Saipan, whose range 6,633km. Now the B737 New Generation has made a great improvement on performance for the empty flight range has reached longer than 6,000km and was capable for area navigation (RNAV). In order to quantitatively evaluating the possibility of a ferry flight from Hawaii directly to Saipan, the developing of RNAV operation computer aided system is very necessary.According to the relevant civil aviation regulations, this paper came up with some points like the precondition of RNAV operation in ocean area, the requirements of airborne navigation equipments and the operation procedure of RNAV. Then it made a specific requirement analysis on the function and performance of the RNAV operation computer aided system, meanwhile designed four function modules including database, route planning, design-making and simple flight plan programming. Based on VB as the developing tool, after the design of RNAV route planning interface, the paper achieved the geographic coordinate calculation of insert waypoints and the track angle and distance of every leg by compiling code relying on principle of orthodromicline calculation, then saved the result as TXT files. Based on JAVA, the paper designed the RNAV design-making interface, which compiling corresponding code according to the design-making process. While the entire precondition was suitable, the system would call out simple flight plan programming interface, achieved the calculation of flight time and fuel consumption by imputing track angle, distance, wind direction/speed, fuel consumption rate and other parameters.To testing the RNAV operation computer aided system, this paper made an assumption that set both B737NG performance parameter and the coordinate of Hawaii airport and Saipan airport as original parameters, supposed the route with strong upwind while combing with the statistic data of wind direction/speed enroute. The result showed :( 1) On the premise of ATC facility guarantee, B737NG was able to made a RNAV ferry flight for its current fuel consumption-14.3ton, from Hawaii to Saipan, was far less than the maximum empty fuel load-21ton. (2) The software achieved both the auxiliary calculation function and design-making function, and the individual performance target was accord with previous design requirements.