A navigation system includes input means (1a) for entering a telephone number; an information storage device (3) for storing telephone-number data (3a), in which a location name inclusive of a set of coordinate is stored for each telephone number, address data (3b) in which an address is stored for each set of coordinates, and map data (3c); a central processor (4) having telephone-number retrieval means (4a) for retrieving, from the information storage device, location coordinates and location name of a telephone number entered by the input means, and address-data retrieval means (4b) for retrieving address data corresponding to the location coordinates of the telephone number entered by the input means; and display means (1b) for displaying a location name and address, which have been retrieved by the central processor, as well as a map centered on the location. Designation and entry of a location are performed by displaying the location name and address retrieved by entry of a telephone number, as well as the map centered on said location, on the display means. Since the amount of data is broken up into the telephone-number data and address data, the amount of telephone-number data can be reduced.

The airspeed limiting performance envelope of a helicopter is converted to a groundspeed envelope by factoring-in the wind speed and direction. A groundspeed command for an unmanned helicopter is provided as a function of the range to the helicopter's destination. The function may be calculated so as to provide a nominal groundspeed command equal to a nominal groundspeed command limit, or the function may be a fixed function to cause the aircraft to creep toward final approach. The cosine and sine of the desired relative flight direction of the aircraft, which is equal to the true bearing to the destination minus the true heading of the aircraft, are utilized to scale the groundspeed command into a longitudinal groundspeed command and a lateral groundspeed command. If one of the groundspeed commands is over a corresponding limit, the other groundspeed command is scaled back so that the vector addition of the two commands will cause flight in the desired direction. Exceedance of either a right or left groundspeed command, as well as saturation of the right or left cyclic pitch channel will cause the aircraft heading to be yawed into the direction of the limit exceedance or channel saturation.

A navigational device in which a position is storable by actuating a control element and this position may be input as a driving destination by re-actuating the control element. This simplifies the input of an often frequented driving destination such as a place of residence.

An on-board automobile navigation system provides route guidance instructions to a user. The system detects a power-down of the vehicle and, in response, determines whether to resume route guidance in response to the next start-up of the vehicle. This determination is made prior to powering down the system. The determination is based on the current position of the vehicle and the computed route. If a determination was made to resume guidance after start-up, the selected destination and the computed route are saved in memory before powering down the system. If a determination was made to resume guidance, then in response to the next start-up of the vehicle, the selected destination and the computed route of the vehicle are recalled from memory, and route guidance is resumed from the current position of the vehicle.

A navigation method and apparatus and a navigation program are provided for guiding a vehicle to a destination along a guide route. An off-route detection unit detects an off-route condition when the vehicle is displaced from the guide route and a guide route searching unit searches or determines, when the off-route detection unit detects an off-route condition, a route from a present position of the vehicle to the destination or return point on the guide route. The guide route determining or searching unit includes a weight factor determining unit for determining a weighting value to modify or scale a road parameter used in determining the guide route, a modifying unit for modifying the parameter based on the weighting value, and a calculating unit for calculating a route from the present position of the vehicle to the destination or the return point on the guide route, as a function of the modified parameter. A display is provided for displaying the guide route to the operator of the vehicle.