diff --git a/y2015/control_loops/python/arm.py b/y2015/control_loops/python/arm.py
index 52c1928..9fa270e 100755
--- a/y2015/control_loops/python/arm.py
+++ b/y2015/control_loops/python/arm.py
@@ -85,9 +85,9 @@
     self.A, self.B = self.ContinuousToDiscrete(
         self.A_continuous, self.B_continuous, self.dt)
 
-    controlability = controls.ctrb(self.A, self.B)
-    print 'Rank of augmented controlability matrix.', numpy.linalg.matrix_rank(
-        controlability)
+    controllability = controls.ctrb(self.A, self.B)
+    print 'Rank of augmented controllability matrix.', numpy.linalg.matrix_rank(
+        controllability)
 
     q_pos = 0.02
     q_vel = 0.300
diff --git a/y2015/control_loops/python/claw.py b/y2015/control_loops/python/claw.py
index 17ea700..cdb76ae 100755
--- a/y2015/control_loops/python/claw.py
+++ b/y2015/control_loops/python/claw.py
@@ -64,7 +64,7 @@
     self.A, self.B = self.ContinuousToDiscrete(
         self.A_continuous, self.B_continuous, self.dt)
 
-    controlability = controls.ctrb(self.A, self.B)
+    controllability = controls.ctrb(self.A, self.B)
 
     print "Free speed is", self.free_speed * numpy.pi * 2.0 / 60.0 / self.G
 
diff --git a/y2015/control_loops/python/elevator.py b/y2015/control_loops/python/elevator.py
index 89e16cd..464011b 100755
--- a/y2015/control_loops/python/elevator.py
+++ b/y2015/control_loops/python/elevator.py
@@ -77,9 +77,9 @@
 
     print self.A
 
-    controlability = controls.ctrb(self.A, self.B)
-    print "Rank of augmented controlability matrix.", numpy.linalg.matrix_rank(
-        controlability)
+    controllability = controls.ctrb(self.A, self.B)
+    print "Rank of augmented controllability matrix.", numpy.linalg.matrix_rank(
+        controllability)
 
     q_pos = 0.02
     q_vel = 0.400