diff --git a/src/FDM/CMakeLists.txt b/src/FDM/CMakeLists.txt
index 8153b4461..9f1b0308e 100644
--- a/src/FDM/CMakeLists.txt
+++ b/src/FDM/CMakeLists.txt
@@ -114,7 +114,6 @@ set(LARCSIM_SOURCES
     ls_matrix.c
     ls_model.c
     ls_step.c
-    ls_trim.c
     navion_aero.c
     navion_engine.c
     navion_gear.c