GPS Glitch APM: EKF variance

[godesady]

link 1 down
APM: Calibrating barometer
link 1 OK
online system 1
Mode STABILIZE
APM: Barometer 1 calibration complete
Init Gyro*APM: ArduCopter V3.7.0-dev (5ffb8bb5)
APM: da48596a14e544a1a480f59eb25918ae
APM: Frame: QUAD
**

Ready to FLY APM: GPS 1: detected as u-blox at 115200 baud
APM: EKF3 waiting for GPS config data
APM: EKF3 IMU0 buffers, IMU=11, OBS=4, OF=10, dt=0.0120
APM: EKF3 IMU1 buffers, IMU=11, OBS=4, OF=10, dt=0.0120
APM: EKF3 IMU0 initialised
APM: EKF3 IMU1 initialised
APM: EKF3 IMU1 initial yaw alignment complete
APM: EKF3 IMU0 initial yaw alignment complete
APM: EKF3 IMU1 tilt alignment complete
APM: EKF3 IMU0 tilt alignment complete
APM: ArduCopter V3.7.0-dev (5ffb8bb5)
APM: da48596a14e544a1a480f59eb25918ae
APM: Frame: QUAD
Got MAVLink msg: COMMAND_ACK {command : 520, result : 0}
APM: EKF3 IMU0 Origin set to GPS
APM: EKF3 IMU1 Origin set to GPS
Flight battery 100 percent
APM: EKF3 IMU0 is using GPS
APM: EKF3 IMU1 is using GPS
Got MAVLink msg: COMMAND_ACK {command : 11, result : 0}
APM: Arming motors
Got MAVLink msg: COMMAND_ACK {command : 400, result : 0}
ARMED
Mode GUIDED
Arming checks disabled
Got MAVLink msg: COMMAND_ACK {command : 22, result : 0}
APM: EKF3 IMU0 in-flight yaw alignment complete
APM: EKF3 IMU1 in-flight yaw alignment complete
Got MAVLink msg: COMMAND_ACK {command : 178, result : 0}
Got MAVLink msg: MISSION_ACK {target_system : 255, target_component : 0, type : 0}
height 10
APM: EKF variance
Mode LAND
APM: GPS Glitch
APM: GPS Glitch cleared
Got MAVLink msg: MISSION_ACK {target_system : 255, target_component : 0, type : 1}
Got MAVLink msg: COMMAND_ACK {command : 178, result : 0}
APM: GPS Glitch
height 0
APM: Crash: Disarming
APM: Disarming motors
DISARMED
Flight battery 90 percent
APM: GPS Glitch cleared
Got MAVLink msg: COMMAND_ACK {command : 11, result : 0}
Mode RTL

can you tell me why GPS Glitch

commonder is

On 1st Terminal(Launch Ardupilot SITL)
sim_vehicle.py -v ArduCopter -f gazebo-iris -m --mav10 --map --console -I0

On 2nd Terminal(Launch Gazebo with demo 3DR Iris model)
gazebo --verbose iris_ardupilot.world