Hi FolksRhett -IIRC the only comment was due to authoring method.Tim - Can you recall the cause ?The affected objectsweren't in any way complex,just simple textured boxes.Don't know if this will assist -Try loading KMSO or OAKN in FSXidentify the disappearing objectsthen checking for those matching objects using ADE, (Lamont Clarke's site's gone),Load the relevant library into Arno's ModelConverterXand inspect the disappearing models for any issues there.Guess onlyIt might be down to vertex orientation.HTHATBPaul

Something with the vertices...could be. I will check around at FSDev about it, seems like it was discussed there one time.