A hand-held movable airplane or boat model is equipped on an outer face with gravity actuated simulations of actual navigational instruments. Two interchangeable compass rose discs are mounted each on a separate split shaft spindle protruding from the model. One disc is asymmetrically weighted to maintain the disc in one orientation while the model, held in a vertical plane, moves and rotates to simulate routes of travel. When used with an indicator on the front center of the model, the weighted disc simulates an azimuth directional gyro. One of the spindles is bored axially to admit an indicator shaft rotatably therethrough. An indicator arrow mounted orthogonally on the outer end of the shaft aligns with an orthogonal extension on the inner end of the shaft below the model. A transparent line extends from the shaft extension through a magnetic movable simulated Non Directional Beacon (NDB) or Radio Beacon (RB) to an edge mounted pulley which maintains a weighted end of the line away from the vertical surface over which the model and NDB/RB are moved. A non-weighted compass rose held stationary by a heading control knob simulates a fixed card Automatic Direction Finder (ADF) or Radio Direction Finder (RDF). The knob, secured within a slot in the model and held against the rose by a tensioned elastic band around the base of the bored spindle, may be turned to rotate the compass rose thereby simulating a rotatable card ADF/RDF. Moving the knob away from the rose in an L-shaped slot and placing the weighted disc on the bored spindle simulates a Radio Magnetic Indicator (RMI). A second indicator may be rotatably mounted in a small bore in the outer end of the first indicator shaft. A second weighted line from the pointer of the second indicator to an elevated edge mounted NDB/RB with the first indicator and weighted disc simulates a double-barred RMI.

This invention provides an inexpensive but accurate mechanical analog computer device for providing information based on the relative positions of two or more indicia bearing members at least one of which is mounted to another of said members for non-rotational orbital movement. More particularly a preferred embodiment of the invention is directed to a visual-mechanical device which simulates ADF and/or VOR navigation such that students and experienced pilots can develop skills at home, and also use the device as a reference tool in actual flight. The device incorporates a disc assembly which revolves or orbits non-rotationally about a beacon representation, driven by a lever which also rotates about the Beacon. The discs and lever have representations of the dials, pointers and windows necessary for unambiguous simulation of ADF and/or VOR navigation without interchange of parts.

A hand-held movable airplane model is equipped on an outer face with an outer rotatable donut shaped disc and an inner stationary black circular disc. The outer disc, having compass markings, is rotated by turning a simulated OBS knob to simulate a course card. Indicator needles and flags on the stationary inner disc simulate V.O.R. and Gliode Slope indicators as they would actually appear on an airplane in similar positions and orientations to those of the model as the model is moved over a vertical surface simulating a flight pattern. All needles and flags on the model rotate on pivot pins through the inner disc. Tabs on the underside of each needle and flag are positioned beneath an elasticised band with a high friction surface. The band stretched around the periphery of the inner disc hold all of the needles and flags in place as they are oriented by hand.