diff --git a/BuildController.gd b/BuildController.gd
index e291e76..6be8193 100644
--- a/BuildController.gd
+++ b/BuildController.gd
@@ -38,6 +38,9 @@ extends Node2D
 
 @onready var craft_menu: Control = get_node("../UI/CraftMenu")
 @onready var craft_interceptor_button: IconButton = get_node("../UI/CraftMenu/InterceptorButton")
+@onready var craft_transporter_button: IconButton = get_node("../UI/CraftMenu/TransporterButton")
+@onready var craft_store_button: IconButton = get_node("../UI/CraftMenu/StoreOreButton")
+@onready var craft_store_label: Label = get_node("../UI/CraftMenu/StoreOreLabel")
 @onready var craft_close_button: IconButton = get_node("../UI/CraftMenu/CloseButton")
 @onready var craft_status: Label = get_node("../UI/CraftMenu/StatusLabel")
 @onready var load_ore_button: IconButton = get_node("../UI/SkillMenu/LoadOreButton")
@@ -113,6 +116,8 @@ func _ready() -> void:
 
 	craft_interceptor_button.pressed.connect(_on_craft_interceptor)
 	load_ore_button.pressed.connect(_on_load_ore)
+	craft_transporter_button.pressed.connect(_on_craft_transporter)
+	craft_store_button.pressed.connect(_on_store_ore)
 	craft_close_button.pressed.connect(func(): craft_menu.visible = false)
 
 	formation_close_button.pressed.connect(func(): formation_menu.visible = false)
@@ -452,10 +457,34 @@ func _refresh_craft_status() -> void:
 	var queued: int = GameState.pending_orders(craft_building_id)
 	var stock: int = GameState.building_stock(craft_building_id)
 	var queue_text: String = "" if queued == 0 else "      Queued %d" % queued
-	craft_status.text = "Interceptor  %d ore      Here %d%s      Fleet %d/%d" % [
-		GameState.SHIP_COST, stock, queue_text,
-		fleet.ships.size(), GameState.max_fleet_size()
+	craft_status.text = "Interceptor %d   Transporter %d      Here %d%s" % [
+		GameState.SHIP_COST, GameState.TRANSPORTER_COST, stock, queue_text
 	]
+	# Nowhere to station one means the order would be refused, so say so
+	# rather than letting the button look available and do nothing.
+	craft_transporter_button.enabled = GameState.has_transport_hub()
+	craft_transporter_button.queue_redraw()
+
+	craft_store_label.text = "Store ore here\nHold %d" % GameState.fleet_cargo
+	craft_store_button.enabled = GameState.fleet_cargo > 0
+	craft_store_button.queue_redraw()
+
+	# A full fleet cannot take another vessel, so the order would be refused.
+	# Showing that on the button is the difference between "not available yet"
+	# and a button that looks live and silently does nothing when pressed.
+	var room: bool = fleet.ships.size() + GameState.ships_owed \
+		+ GameState.pending_orders_of(craft_building_id, GameState.PRODUCT_SHIP) \
+		< GameState.max_fleet_size()
+	craft_interceptor_button.enabled = room
+	craft_interceptor_button.queue_redraw()
+	# One statement of the fleet count, either way round: the capacity line
+	# replaces the plain readout rather than being bolted in front of it.
+	if room:
+		craft_status.text += "      Fleet %d/%d" % [fleet.ships.size(), GameState.max_fleet_size()]
+	else:
+		craft_status.text = "Fleet full %d/%d - research capacity at the mothership\n%s" % [
+			fleet.ships.size(), GameState.max_fleet_size(), craft_status.text
+		]
 
 
 func _on_craft_interceptor() -> void:
@@ -463,7 +492,8 @@ func _on_craft_interceptor() -> void:
 		return
 	# Still refused when there is nowhere to put the vessel - queueing an
 	# order that can never be delivered would just bank ships_owed forever.
-	if fleet.ships.size() + GameState.ships_owed + GameState.pending_orders(craft_building_id) \
+	if fleet.ships.size() + GameState.ships_owed \
+			+ GameState.pending_orders_of(craft_building_id, GameState.PRODUCT_SHIP) \
 			>= GameState.max_fleet_size():
 		craft_status.text = "Fleet is full (%d slots)" % GameState.max_fleet_size()
 		return
@@ -474,7 +504,7 @@ func _on_craft_interceptor() -> void:
 
 
 func _refresh_load_ore() -> void:
-	load_ore_label.text = "Load ore\nBank %d   Hold %d" % [GameState.rocks, GameState.fleet_cargo]
+	load_ore_label.text = "Load ore\nBank %d  Hold %d" % [GameState.rocks, GameState.fleet_cargo]
 	load_ore_button.enabled = GameState.rocks > 0
 	load_ore_button.queue_redraw()
 
@@ -484,6 +514,24 @@ func _on_load_ore() -> void:
 	_refresh_load_ore()
 
 
+func _on_store_ore() -> void:
+	if craft_building_id == 0:
+		return
+	var moved: int = GameState.unload_into_building(craft_building_id)
+	_refresh_craft_status()
+	if moved > 0:
+		craft_status.text = "Stored %d ore here      %s" % [moved, craft_status.text]
+
+
+func _on_craft_transporter() -> void:
+	if craft_building_id == 0:
+		return
+	if not GameState.queue_order(craft_building_id, GameState.PRODUCT_TRANSPORTER):
+		craft_status.text = "Build a Transport Hub first - a transporter needs somewhere to be stationed"
+		return
+	_refresh_craft_status()
+
+
 func _on_formation_changed() -> void:
 	fleet.apply_formation()
 
diff --git a/GameState.gd b/GameState.gd
index 8e6827e..98ffa8b 100644
--- a/GameState.gd
+++ b/GameState.gd
@@ -277,7 +277,7 @@ func add_building(type: String, at_position: Vector2) -> int:
 	var id: int = next_building_id
 	next_building_id += 1
 	buildings.append({
-		"id": id, "type": type, "position": at_position, "stock": 0, "queued": 0,
+		"id": id, "type": type, "position": at_position, "stock": 0, "orders": [],
 	})
 	return id
 
@@ -289,12 +289,22 @@ func find_building(id: int) -> Dictionary:
 	return {}
 
 
-func production_cost(type: String) -> int:
-	# What one order out of this building costs it. 0 means it produces
-	# nothing and cannot be ordered from.
-	if type == BUILDING_SHIP_CRAFTER:
-		return SHIP_COST
-	return 0
+const PRODUCT_SHIP: String = "interceptor"
+const PRODUCT_TRANSPORTER: String = "transporter"
+
+const TRANSPORTER_COST: int = 10
+
+
+func product_cost(product: String) -> int:
+	if product == PRODUCT_TRANSPORTER:
+		return TRANSPORTER_COST
+	return SHIP_COST
+
+
+func can_produce(type: String) -> bool:
+	# Only the ship crafter builds anything. The hub STATIONS transporters,
+	# it does not make them (#12).
+	return type == BUILDING_SHIP_CRAFTER
 
 
 func building_stock(id: int) -> int:
@@ -304,7 +314,29 @@ func building_stock(id: int) -> int:
 
 func pending_orders(id: int) -> int:
 	var b: Dictionary = find_building(id)
-	return 0 if b.is_empty() else int(b.get("queued", 0))
+	return 0 if b.is_empty() else (b.get("orders", []) as Array).size()
+
+
+func pending_orders_of(id: int, product: String) -> int:
+	var b: Dictionary = find_building(id)
+	if b.is_empty():
+		return 0
+	var n: int = 0
+	for o in b.get("orders", []):
+		if o == product:
+			n += 1
+	return n
+
+
+func outstanding_cost(id: int) -> int:
+	# What this building still needs delivered to clear everything queued.
+	var b: Dictionary = find_building(id)
+	if b.is_empty():
+		return 0
+	var need: int = 0
+	for o in b.get("orders", []):
+		need += product_cost(o)
+	return maxi(need - int(b.get("stock", 0)), 0)
 
 
 func deposit_to_building(id: int, amount: int) -> int:
@@ -317,28 +349,43 @@ func deposit_to_building(id: int, amount: int) -> int:
 	return amount
 
 
-func queue_order(id: int) -> bool:
+func queue_order(id: int, product: String = PRODUCT_SHIP) -> bool:
 	var b: Dictionary = find_building(id)
-	if b.is_empty() or production_cost(b.type) <= 0:
+	if b.is_empty() or not can_produce(b.type):
 		return false
-	b.queued = int(b.get("queued", 0)) + 1
+	if product == PRODUCT_TRANSPORTER and not has_transport_hub():
+		# Nowhere to station it. Refused rather than queued, so the player is
+		# told now instead of watching an order sit forever.
+		return false
+	(b.orders as Array).append(product)
 	return true
 
 
 func _advance_production() -> void:
 	for b in buildings:
-		var cost: int = production_cost(b.type)
-		if cost <= 0:
+		if not can_produce(b.type):
 			continue
 		# `while`, not `if`: a delivery big enough to cover several queued
 		# orders should clear them all rather than dribbling one out per
 		# frame.
-		while int(b.get("queued", 0)) > 0 and int(b.get("stock", 0)) >= cost:
+		var orders: Array = b.get("orders", [])
+		while not orders.is_empty():
+			var product: String = String(orders[0])
+			var cost: int = product_cost(product)
+			if int(b.get("stock", 0)) < cost:
+				break
+			if product == PRODUCT_TRANSPORTER and nearest_hub_to(b.position).is_empty():
+				# Every hub was demolished while this sat in the queue. Leave
+				# it queued and the stock untouched rather than producing a
+				# vessel with nowhere to live.
+				break
 			b.stock = int(b.stock) - cost
-			b.queued = int(b.queued) - 1
-			if b.type == BUILDING_SHIP_CRAFTER:
+			orders.pop_front()
+			if product == PRODUCT_TRANSPORTER:
+				_station_transporter(b.position)
+			else:
 				ships_owed += 1
-			order_completed.emit(int(b.id), String(b.type))
+			order_completed.emit(int(b.id), product)
 
 
 func has_mothership() -> bool:
@@ -470,6 +517,7 @@ func _process(delta: float) -> void:
 	# keep completing - while the player is on a planet's surface or nowhere
 	# near either.
 	_advance_production()
+	_advance_transporters(delta)
 	if extractors.is_empty():
 		return
 	for e in extractors:
@@ -486,6 +534,154 @@ func _process(delta: float) -> void:
 			e.progress -= 1.0
 
 
+# --- transporters (#19) ---------------------------------------------------
+
+# Vessels stationed at a transport hub that fetch ore from the mothership and
+# deliver it to whichever building is waiting on it.
+#
+# Simulated HERE rather than by any node, exactly like the extractor haulers
+# above and for the same reason: a route the player is nowhere near still has
+# to run. `progress` drives both the drawn position and the moment the ore
+# actually moves, so what you see and what happens cannot drift apart.
+#
+# Entries are {"hub_id", "state", "target_id", "carrying", "progress",
+# "from", "to"}.
+const TRANSPORTER_SPEED: float = 340.0
+
+const TRANSPORTER_IDLE: String = "idle"
+const TRANSPORTER_TO_MOTHERSHIP: String = "to_mothership"
+const TRANSPORTER_TO_BUILDING: String = "to_building"
+const TRANSPORTER_RETURNING: String = "returning"
+
+var transporters: Array = []
+
+
+func has_transport_hub() -> bool:
+	return not nearest_hub_to(Vector2.ZERO).is_empty()
+
+
+func nearest_hub_to(at: Vector2) -> Dictionary:
+	var best: Dictionary = {}
+	var best_d: float = INF
+	for b in buildings:
+		if b.type != BUILDING_TRANSPORT_HUB:
+			continue
+		var d: float = at.distance_squared_to(b.position)
+		if d < best_d:
+			best_d = d
+			best = b
+	return best
+
+
+func _station_transporter(built_at: Vector2) -> void:
+	# Built at the crafter, then it flies itself to the nearest hub and waits
+	# there for orders (#12).
+	var hub: Dictionary = nearest_hub_to(built_at)
+	if hub.is_empty():
+		return
+	transporters.append({
+		"hub_id": int(hub.id), "state": TRANSPORTER_RETURNING, "target_id": 0,
+		"carrying": 0, "progress": 0.0, "from": built_at, "to": hub.position,
+	})
+
+
+func transporter_position(t: Dictionary) -> Vector2:
+	return (t.from as Vector2).lerp(t.to as Vector2, clampf(t.progress, 0.0, 1.0))
+
+
+func _hub_position(hub_id: int) -> Variant:
+	var hub: Dictionary = find_building(hub_id)
+	return null if hub.is_empty() else hub.position
+
+
+func _begin_leg(t: Dictionary, from: Vector2, to: Vector2, state: String) -> void:
+	t.from = from
+	t.to = to
+	t.state = state
+	t.progress = 0.0
+
+
+func _transporter_inbound_to(building_id: int) -> bool:
+	for t in transporters:
+		if t.state != TRANSPORTER_IDLE and int(t.target_id) == building_id:
+			return true
+	return false
+
+
+func _dispatch_transporters() -> void:
+	var mothership: Variant = get_mothership_position()
+	if mothership == null:
+		return  # nowhere to load from
+	for b in buildings:
+		if outstanding_cost(int(b.id)) <= 0:
+			continue
+		# One at a time per building: without this every idle transporter
+		# would be sent after the same shortfall and they would all arrive
+		# carrying ore nobody needs any more.
+		if _transporter_inbound_to(int(b.id)):
+			continue
+		var chosen: Dictionary = {}
+		var best_d: float = INF
+		for t in transporters:
+			if t.state != TRANSPORTER_IDLE:
+				continue
+			var here: Vector2 = transporter_position(t)
+			var d: float = here.distance_squared_to(b.position)
+			if d < best_d:
+				best_d = d
+				chosen = t
+		if chosen.is_empty():
+			return  # every transporter is busy
+		chosen.target_id = int(b.id)
+		_begin_leg(chosen, transporter_position(chosen), mothership, TRANSPORTER_TO_MOTHERSHIP)
+
+
+func _advance_transporters(delta: float) -> void:
+	if transporters.is_empty():
+		return
+	_dispatch_transporters()
+	for t in transporters:
+		if t.state == TRANSPORTER_IDLE:
+			continue
+		var distance: float = (t.from as Vector2).distance_to(t.to as Vector2)
+		var leg: float = maxf(distance / TRANSPORTER_SPEED, 0.0001)
+		t.progress += delta / leg
+		if t.progress < 1.0:
+			continue
+		t.progress = 1.0
+		_arrive(t)
+
+
+func _arrive(t: Dictionary) -> void:
+	var here: Vector2 = t.to
+	var hub_pos: Variant = _hub_position(int(t.hub_id))
+	match t.state:
+		TRANSPORTER_TO_MOTHERSHIP:
+			var target: Dictionary = find_building(int(t.target_id))
+			var want: int = outstanding_cost(int(t.target_id))
+			var take: int = mini(want, rocks)
+			if take <= 0 or target.is_empty():
+				# Nothing to carry, or the building is gone. Go home empty.
+				t.target_id = 0
+				_begin_leg(t, here, hub_pos if hub_pos != null else here, TRANSPORTER_RETURNING)
+				return
+			rocks -= take
+			t.carrying = take
+			_begin_leg(t, here, target.position, TRANSPORTER_TO_BUILDING)
+		TRANSPORTER_TO_BUILDING:
+			# The ore moves at exactly the moment the vessel arrives.
+			if deposit_to_building(int(t.target_id), int(t.carrying)) <= 0:
+				# Building demolished in transit - put the ore back rather
+				# than quietly destroying it.
+				rocks += int(t.carrying)
+			t.carrying = 0
+			t.target_id = 0
+			_begin_leg(t, here, hub_pos if hub_pos != null else here, TRANSPORTER_RETURNING)
+		TRANSPORTER_RETURNING:
+			t.state = TRANSPORTER_IDLE
+			t.progress = 1.0
+
+
 func can_afford(cost: int) -> bool:
 	return rocks >= cost
 
diff --git a/Main.tscn b/Main.tscn
index 38e9f7e..f9242fe 100644
--- a/Main.tscn
+++ b/Main.tscn
@@ -22,6 +22,7 @@
 [ext_resource type="Script" path="res://NeonPanel.gd" id="20"]
 [ext_resource type="Script" path="res://SkillTreeView.gd" id="21"]
 [ext_resource type="Script" path="res://CargoCounter.gd" id="22"]
+[ext_resource type="Script" path="res://TransporterField.gd" id="23"]
 
 [sub_resource type="ShaderMaterial" id="1"]
 shader = ExtResource("5")
@@ -72,6 +73,9 @@ script = ExtResource("14")
 [node name="HaulerField" type="Node2D" parent="."]
 script = ExtResource("18")
 
+[node name="TransporterField" type="Node2D" parent="."]
+script = ExtResource("23")
+
 [node name="BuildController" type="Node2D" parent="."]
 script = ExtResource("15")
 
@@ -609,8 +613,8 @@ anchor_left = 0.5
 anchor_right = 0.5
 anchor_top = 0.5
 anchor_bottom = 0.5
-offset_left = -74
-offset_right = 74
+offset_left = -234
+offset_right = -86
 offset_top = -74
 offset_bottom = 74
 script = ExtResource("10")
@@ -622,14 +626,70 @@ anchor_left = 0.5
 anchor_right = 0.5
 anchor_top = 0.5
 anchor_bottom = 0.5
-offset_left = -260
-offset_right = 260
+offset_left = -300
+offset_right = -20
 offset_top = 100
 offset_bottom = 200
-theme_override_font_sizes/font_size = 60
+theme_override_font_sizes/font_size = 32
 text = "Interceptor"
 horizontal_alignment = 1
 
+[node name="TransporterButton" type="Control" parent="UI/CraftMenu"]
+anchor_left = 0.5
+anchor_right = 0.5
+anchor_top = 0.5
+anchor_bottom = 0.5
+offset_left = 86
+offset_right = 234
+offset_top = -74
+offset_bottom = 74
+script = ExtResource("10")
+icon = 12
+glow_color = Color(0.95, 0.55, 0.85, 1)
+
+[node name="TransporterLabel" type="Label" parent="UI/CraftMenu"]
+mouse_filter = 2
+anchor_left = 0.5
+anchor_right = 0.5
+anchor_top = 0.5
+anchor_bottom = 0.5
+offset_left = 20
+offset_right = 300
+offset_top = 96
+offset_bottom = 176
+theme_override_font_sizes/font_size = 32
+autowrap_mode = 2
+text = "Transporter"
+horizontal_alignment = 1
+
+[node name="StoreOreButton" type="Control" parent="UI/CraftMenu"]
+anchor_left = 0.5
+anchor_top = 1.0
+anchor_right = 0.5
+anchor_bottom = 1.0
+offset_left = -74
+offset_top = -304
+offset_right = 74
+offset_bottom = -156
+script = ExtResource("10")
+icon = 3
+glow_color = Color(1, 0.78, 0.25, 1)
+
+[node name="StoreOreLabel" type="Label" parent="UI/CraftMenu"]
+mouse_filter = 2
+anchor_left = 0.5
+anchor_top = 1.0
+anchor_right = 0.5
+anchor_bottom = 1.0
+offset_left = -260
+offset_top = -148
+offset_right = 260
+offset_bottom = -24
+theme_override_font_sizes/font_size = 32
+autowrap_mode = 2
+text = "Store ore here"
+horizontal_alignment = 1
+
 [node name="CloseButton" type="Control" parent="UI/CraftMenu"]
 anchor_left = 1.0
 anchor_right = 1.0
@@ -794,33 +854,41 @@ horizontal_alignment = 1
 
 [node name="UnlockButton" type="Control" parent="UI/SkillMenu"]
 anchor_left = 0.5
+anchor_top = 1.0
 anchor_right = 0.5
+anchor_bottom = 1.0
 offset_left = -74.0
-offset_top = 1090.0
+offset_top = -304.0
 offset_right = 74.0
-offset_bottom = 1238.0
+offset_bottom = -156.0
 script = ExtResource("10")
 icon = 5
 glow_color = Color(0.45, 0.9, 0.55, 1)
 
 [node name="LoadOreButton" type="Control" parent="UI/SkillMenu"]
 anchor_left = 0.5
+anchor_top = 1.0
 anchor_right = 0.5
+anchor_bottom = 1.0
 offset_left = -256.0
-offset_top = 1090.0
+offset_top = -304.0
 offset_right = -108.0
-offset_bottom = 1238.0
+offset_bottom = -156.0
 script = ExtResource("10")
 icon = 4
 glow_color = Color(1, 0.78, 0.25, 1)
 
 [node name="LoadOreLabel" type="Label" parent="UI/SkillMenu"]
+mouse_filter = 2
 anchor_left = 0.5
+anchor_top = 1.0
 anchor_right = 0.5
-offset_left = -300.0
-offset_top = 1246.0
-offset_right = -64.0
-offset_bottom = 1296.0
+anchor_bottom = 1.0
+offset_left = -330.0
+offset_top = -150.0
+offset_right = -30.0
+offset_bottom = -14.0
+theme_override_font_sizes/font_size = 28
 horizontal_alignment = 1
 autowrap_mode = 2
 text = "Load ore"
diff --git a/Transporter.gd b/Transporter.gd
new file mode 100644
index 0000000..07b5103
--- /dev/null
+++ b/Transporter.gd
@@ -0,0 +1,38 @@
+extends Node2D
+
+# Purely visual: a transport vessel running a hub -> mothership -> building
+# supply route. Carries no state of its own; GameState owns the simulation
+# and TransporterField creates, positions and frees this to match.
+
+const HULL_COLOR: Color = Color(0.95, 0.55, 0.85)
+
+var laden: bool = false
+
+
+func _ready() -> void:
+	add_to_group("transporters")
+	z_index = -1
+	queue_redraw()
+
+
+func set_laden(value: bool) -> void:
+	if laden == value:
+		return
+	laden = value
+	queue_redraw()
+
+
+func _draw() -> void:
+	# Squat and boxy, in the transport hub's own magenta, so it reads as
+	# "belongs to the hub" and not as an extractor hauler (green) or a fleet
+	# vessel (sharp cyan triangle).
+	var hull: PackedVector2Array = PackedVector2Array([
+		Vector2(0, -16), Vector2(10, -4), Vector2(10, 14), Vector2(-10, 14), Vector2(-10, -4),
+	])
+	NeonDraw.draw_glowing_polygon(self, hull, HULL_COLOR, 1.0)
+	if laden:
+		# A visible payload, so a loaded run is distinguishable from a
+		# deadhead back to the hub at a glance.
+		NeonDraw.draw_glowing_polygon(self, PackedVector2Array([
+			Vector2(-5, 0), Vector2(5, 0), Vector2(5, 9), Vector2(-5, 9),
+		]), HULL_COLOR, 0.85)
diff --git a/Transporter.gd.uid b/Transporter.gd.uid
new file mode 100644
index 0000000..317eb72
--- /dev/null
+++ b/Transporter.gd.uid
@@ -0,0 +1 @@
+uid://u8bqm1f03l2y
diff --git a/Transporter.tscn b/Transporter.tscn
new file mode 100644
index 0000000..d6555a6
--- /dev/null
+++ b/Transporter.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=3]
+
+[ext_resource type="Script" path="res://Transporter.gd" id="1"]
+
+[node name="Transporter" type="Node2D"]
+script = ExtResource("1")
diff --git a/TransporterField.gd b/TransporterField.gd
new file mode 100644
index 0000000..c47ab7d
--- /dev/null
+++ b/TransporterField.gd
@@ -0,0 +1,51 @@
+extends Node2D
+
+# Draws the transport vessels GameState is simulating, and only while they
+# are somewhere the player could see them. Same arrangement as HaulerField,
+# and for the same reason: the simulation is authoritative and the visuals
+# are optional, so a run happening far away costs nothing but still moves
+# ore. Position comes from the very same `progress` that decides when the
+# ore actually changes hands.
+
+@export var visible_radius: float = 2600.0
+
+@onready var fleet: Node2D = get_node("../Fleet")
+
+var transporter_scene: PackedScene = preload("res://Transporter.tscn")
+# index into GameState.transporters -> live node
+var active: Dictionary = {}
+
+
+func _process(_delta: float) -> void:
+	var centre: Vector2 = fleet.get_centroid()
+
+	for i in range(GameState.transporters.size()):
+		var t: Dictionary = GameState.transporters[i]
+		var pos: Vector2 = GameState.transporter_position(t)
+		if pos.distance_to(centre) > visible_radius:
+			_despawn(i)
+			continue
+
+		var node: Node2D = active.get(i)
+		if node == null or not is_instance_valid(node):
+			node = transporter_scene.instantiate()
+			get_parent().add_child(node)
+			active[i] = node
+
+		var previous: Vector2 = node.position
+		node.position = pos
+		node.set_laden(int(t.carrying) > 0)
+		var travel: Vector2 = pos - previous
+		if travel.length() > 0.5:
+			node.rotation = travel.angle() + PI / 2.0
+
+	for key in active.keys():
+		if key >= GameState.transporters.size():
+			_despawn(key)
+
+
+func _despawn(index: int) -> void:
+	var node: Node2D = active.get(index)
+	if node != null and is_instance_valid(node):
+		node.queue_free()
+	active.erase(index)
diff --git a/TransporterField.gd.uid b/TransporterField.gd.uid
new file mode 100644
index 0000000..a42478f
--- /dev/null
+++ b/TransporterField.gd.uid
@@ -0,0 +1 @@
+uid://mrx6p58dog66
diff --git a/tests/_build_menu_preview.gd.uid b/tests/_build_menu_preview.gd.uid
new file mode 100644
index 0000000..5292ec5
--- /dev/null
+++ b/tests/_build_menu_preview.gd.uid
@@ -0,0 +1 @@
+uid://cuns23tjgn7fg
diff --git a/tests/_cargo_readout_preview.gd.uid b/tests/_cargo_readout_preview.gd.uid
new file mode 100644
index 0000000..8434c7f
--- /dev/null
+++ b/tests/_cargo_readout_preview.gd.uid
@@ -0,0 +1 @@
+uid://djp66g3saubh4
diff --git a/tests/_craft_menu_preview.gd b/tests/_craft_menu_preview.gd
new file mode 100644
index 0000000..73dca1f
--- /dev/null
+++ b/tests/_craft_menu_preview.gd
@@ -0,0 +1,27 @@
+extends Node2D
+
+# Preview, not a test. Opens the CraftMenu so its layout can be checked on a
+# real viewport - the mothership's "Load ore" label was falling off the bottom
+# of shorter screens, which no headless test can see.
+#
+#   bash tests/screenshot.sh res://tests/_craft_menu_preview.tscn /tmp/m.png 20 720x1280
+#   ... and again at 720x960 to check a shorter screen format.
+
+
+func _ready() -> void:
+	GameState.buildings.clear()
+	GameState.extractors.clear()
+	GameState.transporters.clear()
+	GameState.rocks = 180
+	GameState.fleet_cargo = 24
+	GameState.unlocked = ["shipyards", "logistics", "freight"]
+	var main: Node = load("res://Main.tscn").instantiate()
+	add_child(main)
+	main.get_node("BuildingField").place(GameState.BUILDING_TRANSPORT_HUB, Vector2(400.0, 0.0))
+	var bc: Node = main.get_node("BuildController")
+	bc.craft_building_id = 1
+	main.get_node("UI/CraftMenu").visible = true
+	if "Craft" == "Craft":
+		bc._refresh_craft_status()
+	else:
+		bc._refresh_load_ore()
diff --git a/tests/_craft_menu_preview.tscn b/tests/_craft_menu_preview.tscn
new file mode 100644
index 0000000..677d6e0
--- /dev/null
+++ b/tests/_craft_menu_preview.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=3]
+
+[ext_resource type="Script" path="res://tests/_craft_menu_preview.gd" id="1"]
+
+[node name="CraftMenuPreview" type="Node2D"]
+script = ExtResource("1")
diff --git a/tests/_skill_menu_preview.gd b/tests/_skill_menu_preview.gd
index 2cb092d..4f74dbc 100644
--- a/tests/_skill_menu_preview.gd
+++ b/tests/_skill_menu_preview.gd
@@ -1,29 +1,27 @@
 extends Node2D
 
-# Preview scene - NOT run by run_tests.sh (underscore prefix). Opens the
-# mothership's research tree with one branch already bought and a node
-# selected, so the laid-out tree, its state colours and the detail panel can
-# all be checked in one render.
+# Preview, not a test. Opens the SkillMenu so its layout can be checked on a
+# real viewport - the mothership's "Load ore" label was falling off the bottom
+# of shorter screens, which no headless test can see.
 #
-#   bash tests/screenshot.sh res://tests/_skill_menu_preview.tscn out.png 30 720x1280
+#   bash tests/screenshot.sh res://tests/_skill_menu_preview.tscn /tmp/m.png 20 720x1280
+#   ... and again at 720x960 to check a shorter screen format.
 
 
 func _ready() -> void:
 	GameState.buildings.clear()
 	GameState.extractors.clear()
-	GameState.reset_progression()
-	GameState.rocks = 60
-	# One branch researched, so the render shows all three node states at
-	# once: done, reachable, and still locked further out.
-	GameState.unlock("shipyards")
-	GameState.unlock("coordination")
-
+	GameState.transporters.clear()
+	GameState.rocks = 180
+	GameState.fleet_cargo = 24
+	GameState.unlocked = ["shipyards", "logistics", "freight"]
 	var main: Node = load("res://Main.tscn").instantiate()
 	add_child(main)
-	main.get_node("AsteroidField").set_process(false)
-	main.get_node("EnemySpawner").set_process(false)
-
-	var controller: Node = main.get_node("BuildController")
-	controller.skill_menu.visible = true
-	controller.skill_tree.selected_id = "wing"
-	controller._refresh_skill_menu("wing")
+	main.get_node("BuildingField").place(GameState.BUILDING_TRANSPORT_HUB, Vector2(400.0, 0.0))
+	var bc: Node = main.get_node("BuildController")
+	bc.craft_building_id = 1
+	main.get_node("UI/SkillMenu").visible = true
+	if "Skill" == "Craft":
+		bc._refresh_craft_status()
+	else:
+		bc._refresh_load_ore()
diff --git a/tests/_transporter_preview.gd b/tests/_transporter_preview.gd
new file mode 100644
index 0000000..68d2b55
--- /dev/null
+++ b/tests/_transporter_preview.gd
@@ -0,0 +1,38 @@
+extends Node2D
+
+# Preview, not a test. A transporter mid-run between the mothership and a
+# building it is supplying, so the #19 vessel can actually be looked at
+# alongside the hub that stations it. Headless draws no pixels.
+#
+#   bash tests/screenshot.sh res://tests/_transporter_preview.tscn /tmp/t.png 25 1280x720
+
+
+func _ready() -> void:
+	GameState.buildings.clear()
+	GameState.extractors.clear()
+	GameState.transporters.clear()
+	GameState.rocks = 200
+	GameState.add_building(GameState.BUILDING_MOTHERSHIP, Vector2(-420.0, 0.0))
+	GameState.add_building(GameState.BUILDING_TRANSPORT_HUB, Vector2(420.0, 0.0))
+
+	# One laden, mid-leg, and one running home empty, so both states show.
+	GameState.transporters.append({
+		"hub_id": 2, "state": GameState.TRANSPORTER_TO_BUILDING, "target_id": 2,
+		"carrying": 8, "progress": 0.45,
+		"from": Vector2(-420.0, 0.0), "to": Vector2(420.0, 0.0),
+	})
+	GameState.transporters.append({
+		"hub_id": 2, "state": GameState.TRANSPORTER_RETURNING, "target_id": 0,
+		"carrying": 0, "progress": 0.5,
+		"from": Vector2(-380.0, 150.0), "to": Vector2(420.0, 150.0),
+	})
+
+	var main: Node = load("res://Main.tscn").instantiate()
+	add_child(main)
+	main.get_node("AsteroidField").set_process(false)
+	main.get_node("EnemySpawner").set_process(false)
+	# Freeze the simulation so the vessels stay where they were placed.
+	GameState.set_process(false)
+	main.get_node("Fleet").move_to(Vector2(0.0, 260.0))
+	var cam: Camera2D = main.get_node("Camera2D")
+	cam.zoom = Vector2(0.85, 0.85)
diff --git a/tests/_transporter_preview.gd.uid b/tests/_transporter_preview.gd.uid
new file mode 100644
index 0000000..7fbf0dc
--- /dev/null
+++ b/tests/_transporter_preview.gd.uid
@@ -0,0 +1 @@
+uid://cqc5de83g4tr2
diff --git a/tests/_transporter_preview.tscn b/tests/_transporter_preview.tscn
new file mode 100644
index 0000000..f3c7618
--- /dev/null
+++ b/tests/_transporter_preview.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=3]
+
+[ext_resource type="Script" path="res://tests/_transporter_preview.gd" id="1"]
+
+[node name="TransporterPreview" type="Node2D"]
+script = ExtResource("1")
diff --git a/tests/test_building_stock_queue.gd.uid b/tests/test_building_stock_queue.gd.uid
new file mode 100644
index 0000000..d21c584
--- /dev/null
+++ b/tests/test_building_stock_queue.gd.uid
@@ -0,0 +1 @@
+uid://b0364sukgpwow
diff --git a/tests/test_cargo_readout.gd.uid b/tests/test_cargo_readout.gd.uid
new file mode 100644
index 0000000..9d85839
--- /dev/null
+++ b/tests/test_cargo_readout.gd.uid
@@ -0,0 +1 @@
+uid://bpldq0su02w1v
diff --git a/tests/test_manual_supply_route.gd.uid b/tests/test_manual_supply_route.gd.uid
new file mode 100644
index 0000000..1b3c8ab
--- /dev/null
+++ b/tests/test_manual_supply_route.gd.uid
@@ -0,0 +1 @@
+uid://bjkqin5w5tah2
diff --git a/tests/test_transport_hub_building.gd.uid b/tests/test_transport_hub_building.gd.uid
new file mode 100644
index 0000000..4599336
--- /dev/null
+++ b/tests/test_transport_hub_building.gd.uid
@@ -0,0 +1 @@
+uid://ctplk4adbsi3a
diff --git a/tests/test_transporter_supply.gd b/tests/test_transporter_supply.gd
new file mode 100644
index 0000000..dbc43e4
--- /dev/null
+++ b/tests/test_transporter_supply.gd
@@ -0,0 +1,207 @@
+extends SceneTree
+
+# Headless gameplay test: run with
+#   godot --headless -s res://tests/test_transporter_supply.gd
+# Forgejo #19 (part 6 of #12): transporters stationed at a hub fetch ore from
+# the mothership and deliver it to whichever building is waiting on it, with
+# no player input at all.
+#
+# Verifies:
+#   1. a transporter is built at the CRAFTER and takes itself to the nearest
+#      hub, rather than appearing at the hub out of nowhere
+#   2. a queued order the crafter cannot pay for is fulfilled end to end
+#      automatically - the whole point of the ticket
+#   3. ore is conserved across the entire route (bank + hold + every
+#      building's stock), at every step, not just at the end
+#   4. ore leaves the bank when it is LOADED, not when the order is placed -
+#      the vessel is carrying something real
+#   5. transporters are not ordered when there is no hub to station them at
+#   6. no unbounded node accumulation: the fleet of transporters is exactly
+#      what was built, however many runs they make
+
+var game_state: Node
+var scene: Node
+var fleet: Node
+var field: Node
+var crafter_id: int = 0
+var hub_id: int = 0
+var stage: int = 0
+var elapsed: float = 0.0
+var total_at_start: int = 0
+var bank_when_ordered: int = 0
+var conservation_broken: bool = false
+# Ore legitimately consumed by completed production. Conservation means
+# "nothing vanishes in TRANSIT", not "the total never falls" - building a
+# vessel spends ore, and that is the one way it is allowed to leave.
+var consumed: int = 0
+
+const MOTHERSHIP_AT: Vector2 = Vector2(0.0, 0.0)
+const HUB_AT: Vector2 = Vector2(600.0, 200.0)
+const CRAFTER_AT: Vector2 = Vector2(900.0, -300.0)
+
+
+func _total() -> int:
+	var sum: int = game_state.rocks + game_state.fleet_cargo
+	for b in game_state.buildings:
+		sum += int(b.get("stock", 0))
+	for t in game_state.transporters:
+		sum += int(t.get("carrying", 0))
+	return sum
+
+
+func _initialize() -> void:
+	game_state = root.get_node("GameState")
+	game_state.buildings.clear()
+	game_state.extractors.clear()
+	game_state.transporters.clear()
+	game_state.rocks = 200
+	game_state.fleet_cargo = 0
+	game_state.ships_owed = 0
+	game_state.unlocked = ["shipyards", "logistics", "freight", "coordination", "wing", "squadron", "armada"]
+	scene = load("res://Main.tscn").instantiate()
+	root.add_child(scene)
+	fleet = scene.get_node("Fleet")
+	field = scene.get_node("BuildingField")
+	game_state.order_completed.connect(_on_order_completed)
+
+
+func _on_order_completed(_building_id: int, product: String) -> void:
+	consumed += game_state.product_cost(product)
+
+
+func _process(delta: float) -> bool:
+	elapsed += delta
+
+	# --- 3. conservation, checked EVERY tick ------------------------------
+	# Ore in flight is the easy thing to lose: a leg that loads without
+	# debiting, or delivers without crediting, would show up here and nowhere
+	# else. Checked continuously rather than at the end, so it cannot be
+	# masked by a later correction.
+	if stage >= 2 and _total() + consumed != total_at_start:
+		conservation_broken = true
+
+	match stage:
+		0:
+			scene.get_node("AsteroidField").set_process(false)
+			scene.get_node("EnemySpawner").set_process(false)
+			for a in get_nodes_in_group("asteroids"):
+				if is_instance_valid(a):
+					a.queue_free()
+
+			field.place(GameState.BUILDING_MOTHERSHIP, MOTHERSHIP_AT)
+			field.place(GameState.BUILDING_SHIP_CRAFTER, CRAFTER_AT)
+			crafter_id = int(game_state.buildings[-1].id)
+
+			# --- 5. no hub yet: a transporter cannot be ordered ----------
+			if game_state.queue_order(crafter_id, GameState.PRODUCT_TRANSPORTER):
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (ordered a transporter with no hub to station it at)")
+				quit(1)
+				return true
+			print("no hub -> transporter order refused")
+
+			field.place(GameState.BUILDING_TRANSPORT_HUB, HUB_AT)
+			hub_id = int(game_state.buildings[-1].id)
+			elapsed = 0.0
+			stage = 1
+			return false
+		1:
+			if elapsed < 0.2:
+				return false
+			# --- 1. build a transporter at the crafter ------------------
+			if not game_state.queue_order(crafter_id, GameState.PRODUCT_TRANSPORTER):
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (could not order a transporter with a hub built)")
+				quit(1)
+				return true
+			game_state.deposit_to_building(crafter_id, GameState.TRANSPORTER_COST)
+			elapsed = 0.0
+			stage = 2
+			total_at_start = _total()
+			return false
+		2:
+			if elapsed < 0.3:
+				return false
+			if game_state.transporters.size() != 1:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (built %d transporters from one order)" % game_state.transporters.size())
+				quit(1)
+				return true
+			var t: Dictionary = game_state.transporters[0]
+			if int(t.hub_id) != hub_id:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (transporter did not take the nearest hub)")
+				quit(1)
+				return true
+			# It must fly FROM the crafter TO the hub, not appear at the hub.
+			# Checked on the leg's endpoints rather than its current position,
+			# which is already partway there by now - and being partway is
+			# the correct behaviour.
+			if (t.from as Vector2).distance_to(CRAFTER_AT) > 1.0:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (transporter's first leg starts at %s, not at the crafter that built it)" % t.from)
+				quit(1)
+				return true
+			if (t.to as Vector2).distance_to(HUB_AT) > 1.0:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (transporter's first leg does not end at the hub: %s)" % t.to)
+				quit(1)
+				return true
+			print("transporter built at the crafter, heading for hub %d" % hub_id)
+			elapsed = 0.0
+			stage = 3
+			return false
+		3:
+			# Give it time to reach the hub and go idle.
+			if elapsed < 4.0:
+				return false
+			if game_state.transporters[0].state != GameState.TRANSPORTER_IDLE:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (never settled at its hub: state=%s)" % game_state.transporters[0].state)
+				quit(1)
+				return true
+			print("stationed at the hub, idle")
+
+			# --- 2 + 4. an order it cannot pay for ----------------------
+			game_state.queue_order(crafter_id, GameState.PRODUCT_SHIP)
+			bank_when_ordered = game_state.rocks
+			elapsed = 0.0
+			stage = 4
+			return false
+		4:
+			# One tick: placing the order must not touch the bank.
+			if elapsed < 0.1:
+				return false
+			if game_state.rocks != bank_when_ordered:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (bank moved on placing the order, before anything was loaded)")
+				quit(1)
+				return true
+			print("order placed, bank untouched at %d" % game_state.rocks)
+			elapsed = 0.0
+			stage = 5
+			return false
+		5:
+			# --- 2. the whole run, with no player input -----------------
+			if game_state.pending_orders(crafter_id) > 0:
+				if elapsed > 25.0:
+					print("TEST_TRANSPORTER_SUPPLY: FAIL (order never fulfilled: transporter state=%s carrying=%d crafter stock=%d)" % [
+						game_state.transporters[0].state,
+						int(game_state.transporters[0].carrying),
+						game_state.building_stock(crafter_id),
+					])
+					quit(1)
+					return true
+				return false
+			if conservation_broken:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (ore created or destroyed somewhere along the route)")
+				quit(1)
+				return true
+			print("order fulfilled automatically in %.1fs, no player input" % elapsed)
+
+			# --- 6. no vessel accumulation ------------------------------
+			if game_state.transporters.size() != 1:
+				print("TEST_TRANSPORTER_SUPPLY: FAIL (%d transporters exist after the run, one was built)" % game_state.transporters.size())
+				quit(1)
+				return true
+			print("still exactly 1 transporter after a full round trip")
+			print("bank=%d crafter stock=%d total=%d + %d consumed = %d (started %d)" % [
+				game_state.rocks, game_state.building_stock(crafter_id), _total(),
+				consumed, _total() + consumed, total_at_start
+			])
+			print("TEST_TRANSPORTER_SUPPLY: PASS")
+			quit(0)
+			return true
+	return false
diff --git a/tests/test_transporter_supply.gd.uid b/tests/test_transporter_supply.gd.uid
new file mode 100644
index 0000000..bfc9fcf
--- /dev/null
+++ b/tests/test_transporter_supply.gd.uid
@@ -0,0 +1 @@
+uid://dxu5orxbivfpa