Originally Posted by
deltahotel
To hold a valid TRE/TRI you need a valid medical. If you only want to work in the Sim &/or have lost your medical you can be SFE/SFI.
You can work in the Sim as a TRI/TRE as I do now.
Chatting to another colleague he queried this with Austro Control (Austria) when he lost his medical and they asked why he wanted to be a SFI/SFE as he could stay as a TRI/TRE for simulator work.