diff --git a/src/Polar.cpp b/src/Polar.cpp
index a5bb0998..6d7e0c0c 100644
--- a/src/Polar.cpp
+++ b/src/Polar.cpp
@@ -1002,7 +1002,7 @@ void Polar::CalculateVMG(int VWi)
     for(int i=0; i<4; i++) {
         double upwind = i < 2 ? 1 : -1;
         double maxVB = 0;
-        float maxW = NAN;
+        double maxW = NAN;
         unsigned int maxWi = 0;
         for(unsigned int Wi = 0; Wi < degree_steps.size(); Wi++) {
             double W = degree_steps[Wi];