diff --git a/src/main/flight/imu.c b/src/main/flight/imu.c
index 5f3c2b3efd..5d4e9e947b 100644
--- a/src/main/flight/imu.c
+++ b/src/main/flight/imu.c
@@ -724,5 +724,5 @@ void imuQuaternionHeadfreeTransformVectorEarthToBody(t_fp_vector_def *v)
 
 bool isUpright(void)
 {
-    return attitudeIsEstablished && getCosTiltAngle() <= smallAngleCosZ;
+    return attitudeIsEstablished && getCosTiltAngle() > smallAngleCosZ;
 }
diff --git a/src/test/unit/flight_imu_unittest.cc b/src/test/unit/flight_imu_unittest.cc
index 324c71652b..bc5fc24414 100644
--- a/src/test/unit/flight_imu_unittest.cc
+++ b/src/test/unit/flight_imu_unittest.cc
@@ -175,7 +175,7 @@ TEST(FlightImuTest, TestSmallAngle)
     imuComputeRotationMatrix();
 
     // expect
-    EXPECT_EQ(true, isUpright());
+    EXPECT_EQ(false, isUpright());
 
     // given
     rMat[0][0] = r1;
@@ -187,7 +187,7 @@ TEST(FlightImuTest, TestSmallAngle)
     imuComputeRotationMatrix();
 
     // expect
-    EXPECT_EQ(true, isUpright());
+    EXPECT_EQ(false, isUpright());
 
     // given
     memset(rMat, 0.0, sizeof(float) * 9);
@@ -196,7 +196,7 @@ TEST(FlightImuTest, TestSmallAngle)
     imuComputeRotationMatrix();
 
     // expect
-    EXPECT_EQ(true, isUpright());
+    EXPECT_EQ(false, isUpright());
 }
 
 // STUBS