Help！Ship model dont show

[08848994d]

Im creating a new type of ship called battlecruisers,they supposed to use similar components with BBs,but with more utilities slots,however in ship designer,ship model didnt show.

Here is my file:

#BOW

ship_section_template = {
key = "BATTLECRUISER_BOW_L2M2"
ship_size = battlecruiser
fits_on_slot = bow
entity = "battleship_bow_L1M1S2_entity"
icon = "GFX_ship_part_core_bow"
icon_frame = 1

# Big guns
weapon_preferences = { weapon_type_kinetic }
ai_weight = {
modifier = {
factor = 1.0
OR = {
has_ai_personality = honorbound_warriors
has_ai_personality = evangelising_zealots
has_ai_personality = democratic_crusaders
}
}
}

component_slot = {
name = "LARGE_GUN_01"
slot_size = large
slot_type = weapon
locatorname = "large_gun_01"
}
component_slot = {
name = "LARGE_GUN_02"
slot_size = large
slot_type = weapon
locatorname = "medium_gun_01"
}

component_slot = {
name = "MEDIUM_GUN_01"
slot_size = medium
slot_type = weapon
locatorname = "small_gun_01"
}

component_slot = {
name = "MEDIUM_GUN_02"
slot_size = medium
slot_type = weapon
locatorname = "small_gun_02"
}

medium_utility_slots = 3
large_utility_slots = 3

cost = 720
}


In ship size file:

@battlecruiser_combat_speed = 0.7
@battlecruiser_combat_rotation = 0.025
@battlecruiser_collision_radius = 5




battlecruiser = {
max_speed = 3.75
acceleration = 0.25
rotation_speed = 0.175
combat_max_speed = @battlecruiser_combat_speed
combat_rotation_speed = @battlecruiser_combat_rotation
collision_radius = @battlecruiser_collision_radius
modifier = {
ship_evasion_mult = -0.5
ship_armor_add = 22
}
max_hitpoints = 2200
size_multiplier = 8
fleet_slot_size = 4
section_slots = { "bow" = { locator = "part1" } "mid" = { locator = "part2" } "stern" = { locator = "part3" } }
num_target_locators = 4
is_space_station = no
icon_frame = 5
base_buildtime = 720
required_spaceport_level = 6
can_have_federation_design = yes
enable_default_design = no #if yes, countries will have an auto-generated design at start

prerequisites = { "tech_spaceport_6" }

class = shipclass_military
required_component_set = "ftl_components"
required_component_set = "combat_computers"
required_component_set = "thruster_components"
required_component_set = "ship_sensor_components"
required_component_set = "ship_aura_components"
required_component_set = "ship_aura_components"
}