Evaluation tests of radars and navigation aids often require continuous positioning of aircraft employed for flight experiment. Therefore, a Loran-C receiver, JNA-760R, a specially ordered model of JNA-760, is equipped for the purpose. Since its accuracy of positioning is most important, calibration test is made by the method of aerial triangulation with a Karl Zeis RMK-21/18 camera, which has a positioning accuracy of the order of 1m. The JNA-760R has a function of distance-distance positioning (ρ-ρ navigation) in addition to the ordinary function of hyperbolic navigation. Test results show superiority of the ρ-ρ method which has an accuracy of about 300m and is enough for evaluation tests of VOR, ASR, etc. However, a rapid turn has caused an error of 800m and hence, it should be avoided.