Functional? Performance?
View attachment 48652
And that poor ET will never fall back into the atmosphere.
(if it like real life space shuttle, then at SFS scale you should drop the ET at about 31km and with periapsis still in atmosphere)
Finally the orbiter went too high, you took it a practically all the way to MEO (if you go by the scale of SFS earth radius, not the atmosphere thickness).
I'm only mentioning this because it's clearly intended to be a STS replica.
Or the magic one from
Armageddon that could go to like moon orbit.