diff --git a/fio.go b/fio.go
index 946565e..d65211b 100644
--- a/fio.go
+++ b/fio.go
@@ -77,6 +77,7 @@ type Files struct {
 	Main        []Main            `json:"Main"`
 	ElastoDyn   []ElastoDyn       `json:"ElastoDyn"`
 	BeamDyn     []BeamDyn         `json:"BeamDyn"`
+	SubDyn      []SubDyn          `json:"SubDyn"`
 	AeroDyn     []AeroDyn         `json:"AeroDyn"`
 	AeroDyn14   []AeroDyn14       `json:"AeroDyn14"`
 	HydroDyn    []HydroDyn        `json:"HydroDyn"`
@@ -336,6 +337,12 @@ type StControl struct {
 	PrescribedForcesFile Path `json:"PrescribedForcesFile"`
 }
 
+type SubDyn struct {
+	FileBase
+	CBMod  Bool    `json:"CBMod"`
+	Nmodes Integer `json:"Nmodes"`
+}
+
 //------------------------------------------------------------------------------
 // Parsing
 //------------------------------------------------------------------------------