diff --git a/src/modules/mavlink/mavlink_main.cpp b/src/modules/mavlink/mavlink_main.cpp
index c53eccdb2a..619e076dfe 100644
--- a/src/modules/mavlink/mavlink_main.cpp
+++ b/src/modules/mavlink/mavlink_main.cpp
@@ -435,7 +435,6 @@ Mavlink::forward_message(const mavlink_message_t *msg, Mavlink *self)
 	}
 }
 
-#ifndef __PX4_POSIX
 int
 Mavlink::get_uart_fd(unsigned index)
 {
@@ -453,7 +452,6 @@ Mavlink::get_uart_fd()
 {
 	return _uart_fd;
 }
-#endif // __PX4_POSIX
 
 int
 Mavlink::get_instance_id()
@@ -810,6 +808,11 @@ Mavlink::get_free_tx_buf()
 
 #endif
 
+	// if we are using network sockets, return max lenght of one packet
+	if (get_protocol() == UDP || get_protocol() == TCP ) {
+		return  1500;
+	}
+
 	return buf_free;
 }
 
diff --git a/src/modules/mavlink/mavlink_main.h b/src/modules/mavlink/mavlink_main.h
index 1b6904655a..4a42f0bce1 100644
--- a/src/modules/mavlink/mavlink_main.h
+++ b/src/modules/mavlink/mavlink_main.h
@@ -123,11 +123,9 @@ public:
 
 	static void		forward_message(const mavlink_message_t *msg, Mavlink *self);
 
-#ifndef __PX4_QURT
 	static int		get_uart_fd(unsigned index);
 
 	int			get_uart_fd();
-#endif
 
 	/**
 	 * Get the MAVLink system id.