diff --git a/apo/QuadArducopter.h b/apo/QuadArducopter.h
index e741deab7b..47c438f123 100644
--- a/apo/QuadArducopter.h
+++ b/apo/QuadArducopter.h
@@ -54,9 +54,9 @@ static const bool rangeFinderUpEnabled = false;
 static const bool rangeFinderDownEnabled = false;
 
 // loop rates
-static const float loopRate = 400; // attitude nav
-static const float loop0Rate = 50; // controller
-static const float loop1Rate = 10; 	// pos nav/ gcs fast
+static const float loopRate = 250; // attitude nav
+static const float loop0Rate = 40; // controller
+static const float loop1Rate = 5; 	// pos nav/ gcs fast
 static const float loop2Rate = 1; 	// gcs slow
 static const float loop3Rate = 0.1;
 
diff --git a/libraries/APO/AP_ArmingMechanism.h b/libraries/APO/AP_ArmingMechanism.h
index 1f68afd1f5..8186af095a 100644
--- a/libraries/APO/AP_ArmingMechanism.h
+++ b/libraries/APO/AP_ArmingMechanism.h
@@ -52,7 +52,7 @@ public:
 private:
 
     AP_HardwareAbstractionLayer * _hal;
-    uint8_t _armingClock;
+    int8_t _armingClock;
     uint8_t _ch1; /// typically throttle channel
     uint8_t _ch2; /// typically yaw channel
     float _ch1Min; /// arms/disarms below this on ch1
diff --git a/libraries/APO/AP_Autopilot.cpp b/libraries/APO/AP_Autopilot.cpp
index 61a52e0ce7..25f5e22674 100644
--- a/libraries/APO/AP_Autopilot.cpp
+++ b/libraries/APO/AP_Autopilot.cpp
@@ -94,13 +94,13 @@ AP_Autopilot::AP_Autopilot(AP_Navigator * navigator, AP_Guide * guide,
 			AP_MavlinkCommand::home.getCommand());
 
 	/*
-	 * Attach loops
+	 * Attach loops, stacking for priority
 	 */
 	hal->debug->println_P(PSTR("attaching loops"));
 	subLoops().push_back(new Loop(loop0Rate, callback0, this));
-	subLoops().push_back(new Loop(loop1Rate, callback1, this));
-	subLoops().push_back(new Loop(loop2Rate, callback2, this));
-	subLoops().push_back(new Loop(loop3Rate, callback3, this));
+	subLoops()[0]->subLoops().push_back(new Loop(loop1Rate, callback1, this));
+	subLoops()[0]->subLoops()[0]->subLoops().push_back(new Loop(loop2Rate, callback2, this));
+	subLoops()[0]->subLoops()[0]->subLoops()[0]->subLoops().push_back(new Loop(loop3Rate, callback3, this));
 
 	hal->debug->println_P(PSTR("running"));
 	hal->gcs->sendText(SEVERITY_LOW, PSTR("running"));
@@ -162,7 +162,7 @@ void AP_Autopilot::callback1(void * data) {
 	 * slow navigation loop update
 	 */
 	if (apo->getNavigator()) {
-		apo->getNavigator()->updateSlow(apo->subLoops()[1]->dt());
+		apo->getNavigator()->updateSlow(apo->subLoops()[0]->subLoops()[0]->dt());
 	}
 
 	/*