Got this assertion failed error:
My fighters finished intercepting another UFO and were returning to base. Suddenly a UFO appeared and started flying toward my interceptor. So I let my fighters fly to base for rearming and when they entered base, the UFO dissapeared from radar. The base has no radar because i deleted it and started building advanced radar. Minutes later I started my fighters again and as soon as i unpaused the game, got this crash. And the crash is replicatable.
Where are the savegames located? I could also upload my save for you to debug.
edit: Game version 2.3