/usr/include/simgear/scene/model/ is in libsimgear-dev 3.0.0-6+b2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/simgear/scene/model/BVHDebugCollectVisitor.hxx
/usr/include/simgear/scene/model/BVHPageNodeOSG.hxx
/usr/include/simgear/scene/model/BoundingVolumeBuildVisitor.hxx
/usr/include/simgear/scene/model/CheckSceneryVisitor.hxx
/usr/include/simgear/scene/model/ConditionNode.hxx
/usr/include/simgear/scene/model/ModelRegistry.hxx
/usr/include/simgear/scene/model/PrimitiveCollector.hxx
/usr/include/simgear/scene/model/SGClipGroup.hxx
/usr/include/simgear/scene/model/SGInteractionAnimation.hxx
/usr/include/simgear/scene/model/SGMaterialAnimation.hxx
/usr/include/simgear/scene/model/SGOffsetTransform.hxx
/usr/include/simgear/scene/model/SGPickAnimation.hxx
/usr/include/simgear/scene/model/SGReaderWriterXML.hxx
/usr/include/simgear/scene/model/SGRotateTransform.hxx
/usr/include/simgear/scene/model/SGScaleTransform.hxx
/usr/include/simgear/scene/model/SGText.hxx
/usr/include/simgear/scene/model/SGTrackToAnimation.hxx
/usr/include/simgear/scene/model/SGTranslateTransform.hxx
/usr/include/simgear/scene/model/animation.hxx
/usr/include/simgear/scene/model/model.hxx
/usr/include/simgear/scene/model/modellib.hxx
/usr/include/simgear/scene/model/particles.hxx
/usr/include/simgear/scene/model/persparam.hxx
/usr/include/simgear/scene/model/placement.hxx