Having trouble getting UpVector while tweening to make a rocket, is there any solution to this?

Hello,

Im currently trying to figure out how to make a spaceship with the roblox TweenService and its all going good so far until i started 'tweening', there is nothing 'wrong' with my code. I want to get the UpVector of a part and tween it from there but the parts instead of going straight up they go a little to the side.

local tweenService = game:GetService("TweenService")

-- These three parts are wielded together with stage 2 as 'center' part
local Stage1 = script.Parent:WaitForChild("Stage1")
local Stage2 = script.Parent:WaitForChild("Stage2")
local finalStage = script.Parent:WaitForChild("FinalStage") --

local studs = script.Parent:WaitForChild("Studs").Value -- how high up it should go (set to 50)

local stage1Fire = Stage1:WaitForChild("Fire"):WaitForChild("ParticleEmitter") -- ignore this

local luanchButton = script.Parent:WaitForChild("Luanch"):WaitForChild("Detector")

local tweenInfo = TweenInfo.new(
    script.Parent.MaxVel.Value / 60, -- just so i could set studs per minute
    Enum.EasingStyle.Quad,
    Enum.EasingDirection.In,
    0,
    false,
    0
)

local function luanch()
    local properties = {
        CFrame = CFrame.new(Stage2.CFrame.UpVector * Vector3.new(1, studs, 1)) -- I think its somwhere here the problem is.
    }

    local tween = tweenService:Create(Stage2, tweenInfo, properties)

    tween:Play()
end

luanchButton.Triggered:Connect(luanch) -- Im using a ProximityPrompt 

I have created a video here if i have been bad at explaning

Thanks for taking your time!