Let us consider the pitch angle – exemplary results are illustrated in Fig. 3 (results obtained for the roll angle were very similar). The indication error en (n = 1, …, 5) expressed over axis y has been defined as a difference between the value of the pitch ϕ applied by means of the test station and the value determined with respect to the average of relevant indications of the tested sensor, employing Eq. (2)-(7), (9), (11)