diff --git a/src/FDM/JSBSim/models/propulsion/Makefile.am b/src/FDM/JSBSim/models/propulsion/Makefile.am
index 9a5f0a2e4..f78f21c73 100644
--- a/src/FDM/JSBSim/models/propulsion/Makefile.am
+++ b/src/FDM/JSBSim/models/propulsion/Makefile.am
@@ -1,22 +1,14 @@
 includedir = @includedir@/JSBSim/models/propulsion
 
-LIBRARY_SOURCES = FGElectric.cpp FGEngine.cpp FGForce.cpp FGNozzle.cpp \
+noinst_LIBRARIES = libPropulsion.a
+
+libPropulsion_a_SOURCES = \
+                         FGElectric.cpp FGEngine.cpp FGForce.cpp FGNozzle.cpp \
                          FGPiston.cpp FGPropeller.cpp FGRocket.cpp \
                          FGTank.cpp FGThruster.cpp FGTurbine.cpp FGTurboProp.cpp
 
-LIBRARY_INCLUDES = FGElectric.h FGEngine.h FGForce.h FGNozzle.h FGPiston.h \
+noinst_HEADERS = FGElectric.h FGEngine.h FGForce.h FGNozzle.h FGPiston.h \
                   FGPropeller.h FGRocket.h FGTank.h FGThruster.h \
                   FGTurbine.h FGTurboProp.h
 
-if BUILD_LIBRARIES
-noinst_LTLIBRARIES = libPropulsion.la
-include_HEADERS = $(LIBRARY_INCLUDES)
-libPropulsion_la_SOURCES = $(LIBRARY_SOURCES)
-libPropulsion_la_CXXFLAGS = $(AM_CXXFLAGS)
-else
-noinst_LIBRARIES = libPropulsion.a
-noinst_HEADERS = $(LIBRARY_INCLUDES)
-libPropulsion_a_SOURCES = $(LIBRARY_SOURCES)
-endif
-
 INCLUDES = -I$(top_srcdir)/src -I../../