UPLINK DATA INDICATION

A method for a wireless device of an unmanned aerial vehicle (UAV) is described herein. In one embodiment the method includes transmitting - by the wireless device to a mobility management entity (MME) - an attach request message that comprises an identifier of the wireless device and a first session management message for establishing a packet data network (PDN) connection of the wireless device. The first session management message comprises an access point name (APN) and an identifier of the UAV. The method further includes receiving - from the MME - an attach accept message comprising a second session management message for establishing the PDN connection of the wireless device. The second session management message comprises a first parameter indicating that transmission of uplink data via the PDN connection is not allowed until the wireless device receives a second parameter indicating that transmission of uplink data via the PDN connection is allowed. Furthermore, the method includes, based on receiving the second parameter indicating that transmission of uplink data via the PDN connection is allowed, sending - by the wireless device to a PDN gateway (PGW) - one or more uplink packets associated with the PDN connection. Moreover, a corresponding method for the PGW, as well as related methods, apparatuses, devices and systems are described.