Problem spawning a prop

I made a sort of set adv.dupe code, where it spawns a very simple plane. It spawns fine, but when i get to Body:Spawn() or Wing1:Spawn() it says it cant create the physics object for {insert model name here}!
Why would this be?

[lua]
function spawnplane()
Ents = ents.FindByClass(“info_player_start”)
SpawPos = Ents[math.random(1,#Ents)]:GetPos()

Wing1 = ents.Create(“prop_physics”)
Wing2 = ents.Create(“prop_physics”)
Body = ents.Create(“prop_physics”)

Wing1:SetModel(“models/props_phx/construct/metal_plate1x2.mdl”)
Wing2:SetModel(“models/props_phx/construct/metal_plate1x2.mdl”)
Body:SetModel(“models/hunter/blocks/cube075x3x075.mdl”)

Body:SetPos(SpawPos+Vector(5,0,20))
Wing1:SetPos(SpawPos + Vector(50,0,25))
Wing2:SetPos(SpawPos + Vector(-50,0,25))

Body:SetAngles(Angle(0,0,0))
Wing1:SetAngles(Angle(0,90,0))
Wing2:SetAngles(Angle(0,90,0))

Bodbone = Body.PhysicsBone
W1bone = Wing1.PhysicsBone
W2bone = Wing2.PhysicsBone

Body:Spawn()
Wing1:Spawn()
Wing2:Spawn()

constraint.Weld(Body,Wing1,Bodbone,W1bone,0,1)
constraint.Weld(Body,Wing2,Bodbone,W2bone,0,1)
return Body
end
[/lua]