diff --git a/libraries/AP_Motors/AP_MotorsHeli.h b/libraries/AP_Motors/AP_MotorsHeli.h
index 88910c8fb2..0677615c96 100644
--- a/libraries/AP_Motors/AP_MotorsHeli.h
+++ b/libraries/AP_Motors/AP_MotorsHeli.h
@@ -56,10 +56,6 @@ public:
         AP_Motors(loop_rate, speed_hz)
     {
         AP_Param::setup_object_defaults(this, var_info);
-
-        // initialise flags
-        _heliflags.landing_collective = 0;
-        _heliflags.rotor_runup_complete = 0;
     };
 
     // init
diff --git a/libraries/AP_Motors/AP_MotorsMulticopter.cpp b/libraries/AP_Motors/AP_MotorsMulticopter.cpp
index 568775f499..b4f3cd6db5 100644
--- a/libraries/AP_Motors/AP_MotorsMulticopter.cpp
+++ b/libraries/AP_Motors/AP_MotorsMulticopter.cpp
@@ -190,17 +190,11 @@ const AP_Param::GroupInfo AP_MotorsMulticopter::var_info[] = {
 AP_MotorsMulticopter::AP_MotorsMulticopter(uint16_t loop_rate, uint16_t speed_hz) :
     AP_Motors(loop_rate, speed_hz),
     _spool_mode(SHUT_DOWN),
-    _spin_up_ratio(0.0f),
     _lift_max(1.0f),
-    _throttle_limit(1.0f),
-    _throttle_thrust_max(0.0f),
-    _disarm_safety_timer(0)
+    _throttle_limit(1.0f)
 {
     AP_Param::setup_object_defaults(this, var_info);
 
-    // disable all motors by default
-    memset(motor_enabled, false, sizeof(motor_enabled));
-
     // setup battery voltage filtering
     _batt_voltage_filt.set_cutoff_frequency(AP_MOTORS_BATT_VOLT_FILT_HZ);
     _batt_voltage_filt.reset(1.0f);
diff --git a/libraries/AP_Motors/AP_Motors_Class.cpp b/libraries/AP_Motors/AP_Motors_Class.cpp
index 6f14147e76..5a55af40a8 100644
--- a/libraries/AP_Motors/AP_Motors_Class.cpp
+++ b/libraries/AP_Motors/AP_Motors_Class.cpp
@@ -33,22 +33,11 @@ AP_Motors *AP_Motors::_instance;
 AP_Motors::AP_Motors(uint16_t loop_rate, uint16_t speed_hz) :
     _loop_rate(loop_rate),
     _speed_hz(speed_hz),
-    _roll_in(0.0f),
-    _pitch_in(0.0f),
-    _yaw_in(0.0f),
-    _throttle_in(0.0f),
-    _throttle_avg_max(0.0f),
     _throttle_filter(),
     _spool_desired(DESIRED_SHUT_DOWN),
-    _air_density_ratio(1.0f),
-    _motor_fast_mask(0)
+    _air_density_ratio(1.0f)
 {
     _instance = this;
-    
-    // init other flags
-    _flags.armed = false;
-    _flags.interlock = false;
-    _flags.initialised_ok = false;
 
     // setup throttle filtering
     _throttle_filter.set_cutoff_frequency(0.0f);