diff --git a/rotmat.py b/rotmat.py
index e07718b99..86bd1edd5 100755
--- a/rotmat.py
+++ b/rotmat.py
@@ -24,7 +24,7 @@
 '''
 from __future__ import print_function
 
-from math import sin, cos, sqrt, asin, atan2, pi, acos
+from math import sin, cos, sqrt, asin, atan2, pi, acos, radians
 
 
 class Vector3(object):
@@ -423,7 +423,7 @@ def __init__(self, name, roll, pitch, yaw):
         self.pitch = pitch
         self.yaw = yaw
         self.r = Matrix3()
-        self.r.from_euler(self.roll, self.pitch, self.yaw)
+        self.r.from_euler(radians(self.roll), radians(self.pitch), radians(self.yaw))
         self.rt = self.r.transposed()
 
 # the rotations used in APM