diff --git a/src/game.cpp b/src/game.cpp
index 32c1d69..893b601 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -126,18 +126,18 @@ selectOrbit(GameState* gs, GameOrbit* orbit)
 
 bool
 addManeuver(GameOrbit* orbit,
-			double anomaly,
-			vec3 impulse_vector,
+			ImpulseType impulse_type,
+			double true_anomaly,
 			double impulse_delta_v)
 {
-	assert(orbit);
+	ManeuverNode& node = orbit->maneuver;
 
-	if (anomaly < -M_PI || anomaly > M_PI) {
-		LOGF(Error, "invalid true anomaly: %f\n", anomaly);
+	if (true_anomaly < -M_PI || true_anomaly > M_PI) {
+		LOGF(Error, "invalid true true_anomaly: %f\n", true_anomaly);
 		return false;
 	}
 
-	if (orbit->maneuver.active) {
+	if (node.active) {
 		LOGF(Warning, "cannot add multiple maneuvers (yet)\n");
 		return false;
 	}
@@ -147,21 +147,34 @@ addManeuver(GameOrbit* orbit,
 		return false;
 	}
 
-	orbit->maneuver.true_anomaly = anomaly;
-	//orbit->maneuver.impulse_vector = ...
-	orbit->maneuver.impulse_delta_v = impulse_delta_v;
-	orbit->maneuver.active = true;
+	node.impulse_type = impulse_type;
+	// TODO: thrust calculations
+	//double flight_path_angle = orbit->system.sat.gamma;
+	//node.impulse_vector.x = ...
 
-	return true;
+	if (node.impulse_type == ImpulseType::PROGRADE) {
+		LOGF(Debug, "adding prograde maneuver\n");
+		node.true_anomaly = true_anomaly;
+		node.impulse_delta_v = impulse_delta_v;
+		node.active = true;
+
+		return true;
+	}
+
+	LOGF(Warning, "failed to add maneuver\n");
+	assert(0);
+	return false;
 }
 
 void
 removeManeuver(GameOrbit* orbit)
 {
-	assert(orbit);
 	// TODO: multiple maneuver nodes
-	// NOTE: implicitly sets orbit->maneuver.active to false
-	orbit->maneuver = {0};
+	ManeuverNode& node = orbit->maneuver;
+	node.impulse_type = ImpulseType::NONE;
+	node.true_anomaly = 0.f;
+	node.impulse_delta_v = 0.f;
+	node.active = false;
 }
 
 // NOTE: test if the maneuver node would have occured between 2 orbit positions
@@ -194,7 +207,7 @@ applyManeuver(GameOrbit* orbit)
 	LOGF(Debug, "applying maneuver\n");
 
 	// FIXME: assuming prograde impulse vector
-	assert(orbit->maneuver.impulse_type == ManeuverType::PROGRADE);
+	assert(orbit->maneuver.impulse_type == ImpulseType::PROGRADE);
 
 	// re-calculate state vectors at the maneuver node
 	TwoBodySystem& sys = orbit->system;
@@ -223,8 +236,6 @@ applyManeuver(GameOrbit* orbit)
 	assert(utilCStrMatch(buf->name, "position"));
 	assert(buf->data_size == orbit->e3d.vert_count * sizeof(vec3));
 	updateGLBuffer(buf, orbit->e3d.vertices);
-
-	removeManeuver(orbit);
 }
 
 // internal
diff --git a/src/game.h b/src/game.h
index c82e0c5..b69a390 100644
--- a/src/game.h
+++ b/src/game.h
@@ -19,8 +19,9 @@ struct Ellipse3D
 	uint vert_count;
 };
 
-enum struct ManeuverType
+enum struct ImpulseType
 {
+	NONE,
 	PROGRADE,
 	RETROGRADE,
 	INCLINATION_CHANGE,
@@ -31,13 +32,13 @@ enum struct ManeuverType
 
 struct ManeuverNode
 {
+	ImpulseType impulse_type;
 	double true_anomaly;
-	vec3 impulse_vector;
-	ManeuverType impulse_type;
 	double impulse_delta_v;
-	// TODO: thrust calculations
-
 	bool active;
+
+	// TODO: thrust calculations
+	//vec3 impulse_vector;
 };
 
 struct GameOrbit
@@ -86,7 +87,9 @@ void ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d);
 
 void selectOrbit(GameState* gs, GameOrbit* orbit);
 
-bool addManeuver(GameOrbit* orbit, double anomaly, vec3 impulse_vector,
+bool addManeuver(GameOrbit* orbit,
+		ImpulseType impulse_type,
+		double true_anomaly,
 		double impulse_delta_v);
 
 void removeManeuver(GameOrbit* orbit);
diff --git a/src/gooey.cpp b/src/gooey.cpp
index feba60d..662808a 100644
--- a/src/gooey.cpp
+++ b/src/gooey.cpp
@@ -249,6 +249,7 @@ drawManeuverWindow(GameState* gs)
 			SliderScalar("maneuver anomaly", ImGuiDataType_Double, &anom,
 					&min_anom, &max_anom, "%.19f");
 
+			// FIXME: map ImpulseType to strings for UI
 			// select maneuver vector
 			const char* items[] = {
 				"prograde",
@@ -262,7 +263,7 @@ drawManeuverWindow(GameState* gs)
 			InputFloat("impulse dv, km/s", &dv, 0.1, 4.0, "%.1f");
 
 			if (Button("apply")) {
-				if (!addManeuver(orbit, anom, vec3(), dv)) {
+				if (!addManeuver(orbit, ImpulseType::PROGRADE, anom, dv)) {
 					// flash a color or something?
 				}
 			}
diff --git a/src/main.cpp b/src/main.cpp
index 76d463b..352733d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -205,7 +205,7 @@ loadScene(GameState* gs, RenderState* rs)
 	double a = 26564.5;		// semi-major axis in km
 	double e = 0.7411;		// eccentricity
 	GameOrbit* go_1 = loadOrbit(gs, rs, body, orbitInit(a, e), rg, "sat_01");
-	addManeuver(go_1, M_PI / 4, vec3(), 0.1);
+	addManeuver(go_1, ImpulseType::PROGRADE, M_PI / 4, 0.2);
 
 	double a_2 = r + 10000;
 	double e_2 = 0;
@@ -270,6 +270,7 @@ updateOrbit(GameOrbit* orbit, bool running, double time_step)
 					orbit->system.sat.theta))
 		{
 			applyManeuver(orbit);
+			removeManeuver(orbit);
 		}
 	}
 }