An interface unit for use in updating software of an aircraft component on board an aircraft. The interface unit comprises a first interface to connect to a server providing one or more software updates for upload to the aircraft component, and a second interface to connect to the aircraft component. The interface unit further comprises a receiving component configured to receive a software update from the server via the first interface for upload to the aircraft component, and an uploading component configured to upload the received software update to the aircraft component via the second interface.
