From 8cfde42e157f23a711d81c2f7544db0640536edf Mon Sep 17 00:00:00 2001
From: Paul Riseborough <p-riseborough@live.com.au>
Date: Tue, 15 Sep 2015 17:17:05 +1000
Subject: [PATCH] AP_NavEKF: Ensure bad mag data cannot cause the heading to
 reset too often

---
 libraries/AP_NavEKF/AP_NavEKF.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libraries/AP_NavEKF/AP_NavEKF.cpp b/libraries/AP_NavEKF/AP_NavEKF.cpp
index dbc1bdae8e..8d7212bcb3 100644
--- a/libraries/AP_NavEKF/AP_NavEKF.cpp
+++ b/libraries/AP_NavEKF/AP_NavEKF.cpp
@@ -5232,6 +5232,8 @@ bool NavEKF::calcGpsGoodToAlign(void)
         Vector3f eulerAngles;
         getEulerAngles(eulerAngles);
         state.quat = calcQuatAndFieldStates(eulerAngles.x, eulerAngles.y);
+        // reset timer to ensure that bad magnetometer data cannot cause a heading reset more often than every 5 seconds
+        magYawResetTimer_ms = imuSampleTime_ms;
     }
 
     // fail if magnetometer innovations are outside limits indicating bad yaw