diff --git a/aerodynamic_analysis/src/methods/liftingLinePolar.cpp b/aerodynamic_analysis/src/methods/liftingLinePolar.cpp
index 8231e7ea58163147bea257f4818cdd7efb326519..cd6bfd831c0017aa9d10a0f545bd8d81fbb7017d 100644
--- a/aerodynamic_analysis/src/methods/liftingLinePolar.cpp
+++ b/aerodynamic_analysis/src/methods/liftingLinePolar.cpp
@@ -248,7 +248,7 @@ double liftingLinePolar::getCLmax_clean(double Mach) {
     // (small) influence of sweep -> assumption delta y ~ 2.1
     double CLmax2Clmax_phiLE0   = 0.9;  // [Ray18] Fig. 12.8
     double CLmax2Clmax_phiLE60  = 0.8;  // [Ray18] Fig. 12.8
-    double CLmax2Clmax_phiLE    = CLmax2Clmax_phiLE0 + (CLmax2Clmax_phiLE60 - CLmax2Clmax_phiLE0) / (cos(convertDegree(RADIAN, 60)) - 1.) * (cos(phi_LE_rad) - 1.);  // [Ray18] Fig. 12.8
+    double CLmax2Clmax_phiLE    = CLmax2Clmax_phiLE0 + (CLmax2Clmax_phiLE60 - CLmax2Clmax_phiLE0) / (cos(convertUnit(DEGREE, RADIAN, 60)) - 1.) * (cos(phi_LE_rad) - 1.);  // [Ray18] Fig. 12.8
     double CLmax_inc            = CLmax2Clmax_phiLE * Clmax_sec;
     // Decrease due to Mach number
     double delta_CLmax_Ma06 = -0.2 * cos(phi_LE_rad);  // according to [Ray18] Fig. 12.9 (not exact, but influence neglectable --> not too big)