diff --git a/src/modules/commander/CMakeLists.txt b/src/modules/commander/CMakeLists.txt
index c46780167e..81094d3de7 100644
--- a/src/modules/commander/CMakeLists.txt
+++ b/src/modules/commander/CMakeLists.txt
@@ -39,7 +39,6 @@ px4_add_module(
 	STACK_MAIN 4096
 	STACK_MAX 2450
 	COMPILE_FLAGS
-		-Wno-cast-align # TODO: fix and enable
 	SRCS
 		accelerometer_calibration.cpp
 		airspeed_calibration.cpp
diff --git a/src/modules/commander/arm_auth.cpp b/src/modules/commander/arm_auth.cpp
index 4dbd79b799..5be6cc73b4 100644
--- a/src/modules/commander/arm_auth.cpp
+++ b/src/modules/commander/arm_auth.cpp
@@ -57,13 +57,16 @@ static enum {
 	ARM_AUTH_MISSION_APPROVED
 } state = ARM_AUTH_IDLE;
 
-struct packed_struct {
-	uint8_t authorizer_system_id;
-	union {
-		uint16_t auth_method_arm_timeout_msec;
-		uint16_t auth_method_two_arm_timeout_msec;
-	} auth_method_param;
-	uint8_t authentication_method;
+union {
+	struct {
+		uint8_t authorizer_system_id;
+		union {
+			uint16_t auth_method_arm_timeout_msec;
+			uint16_t auth_method_two_arm_timeout_msec;
+		} auth_method_param;
+		uint8_t authentication_method;
+	} __attribute__((packed)) struct_value;
+	int32_t param_value;
 } arm_parameters;
 
 static uint8_t *system_id;
@@ -81,7 +84,7 @@ static void arm_auth_request_msg_send()
 	vehicle_command_s vcmd{};
 	vcmd.timestamp = hrt_absolute_time();
 	vcmd.command = vehicle_command_s::VEHICLE_CMD_ARM_AUTHORIZATION_REQUEST;
-	vcmd.target_system = arm_parameters.authorizer_system_id;
+	vcmd.target_system = arm_parameters.struct_value.authorizer_system_id;
 
 	uORB::PublicationQueued<vehicle_command_s> vcmd_pub{ORB_ID(vehicle_command)};
 	vcmd_pub.publish(vcmd);
@@ -105,7 +108,7 @@ static uint8_t _auth_method_arm_req_check()
 	arm_auth_request_msg_send();
 
 	hrt_abstime now = hrt_absolute_time();
-	auth_timeout = now + (arm_parameters.auth_method_param.auth_method_arm_timeout_msec * 1000);
+	auth_timeout = now + (arm_parameters.struct_value.auth_method_param.auth_method_arm_timeout_msec * 1000);
 	state = ARM_AUTH_WAITING_AUTH;
 
 	while (now < auth_timeout) {
@@ -157,7 +160,7 @@ static uint8_t _auth_method_two_arm_check()
 	arm_auth_request_msg_send();
 
 	hrt_abstime now = hrt_absolute_time();
-	auth_timeout = now + (arm_parameters.auth_method_param.auth_method_arm_timeout_msec * 1000);
+	auth_timeout = now + (arm_parameters.struct_value.auth_method_param.auth_method_arm_timeout_msec * 1000);
 	state = ARM_AUTH_WAITING_AUTH;
 
 	mavlink_log_critical(mavlink_log_pub, "Arm auth: Requesting authorization...");
@@ -167,8 +170,8 @@ static uint8_t _auth_method_two_arm_check()
 
 uint8_t arm_auth_check()
 {
-	if (arm_parameters.authentication_method < ARM_AUTH_METHOD_LAST) {
-		return arm_check_method[arm_parameters.authentication_method]();
+	if (arm_parameters.struct_value.authentication_method < ARM_AUTH_METHOD_LAST) {
+		return arm_check_method[arm_parameters.struct_value.authentication_method]();
 	}
 
 	return vehicle_command_ack_s::VEHICLE_RESULT_DENIED;
@@ -177,7 +180,7 @@ uint8_t arm_auth_check()
 void arm_auth_update(hrt_abstime now, bool param_update)
 {
 	if (param_update) {
-		param_get(param_arm_parameters, (int32_t *)&arm_parameters);
+		param_get(param_arm_parameters, &arm_parameters.param_value);
 	}
 
 	switch (state) {
@@ -280,5 +283,5 @@ void arm_auth_init(orb_advert_t *mav_log_pub, uint8_t *sys_id)
 
 enum arm_auth_methods arm_auth_method_get()
 {
-	return (enum arm_auth_methods) arm_parameters.authentication_method;
+	return (enum arm_auth_methods) arm_parameters.struct_value.authentication_method;
 }