SpaceBird Heavy Reusable Shuttle on the shoulder of a Modernized Saturn VM stage. Saturn VM stage uses four smaller ignitable descent Rocket engines replace its original centre engine, and other F1 engines of Saturn V have been kept.

Its landing status is here:
https://www.simpleplanes.com/a/iE8J8t/SpaceBird-Heavy-Reusable-Shuttle-block-2

General Instructions:
AG 1 to open payload bay.
AG 2 to release drag parachute.

Spacebird Reusable Shuttle Aerodynamic Concept Plane Optimized Version, using NACA 0009 airfoil inner, NACA0013.5 airfoil outer wing.

When the wings unfolded, its aerodynamic would be similar with Republic XF91.

SpaceBird Reusable Shuttle Aerodynamic Concept plane is a kind of small Slace shuttle using retractable wing in order to decrease the area of heat shield bricks, making it safer and more efficient than space shuttle.

The engine arrangement of Recycleable Booster:

This design aims at decreasing the area of heat shield as much as it could while reentry the atmosphere. Heat shield bricks are not only heavy but also more dangerous if it had a hole while reentry.

Its primary wings fold up while reentry, it uses RCS, V-shaped tail and body flaps to control its attitude. Its V-Shaped tail could control its Pitch and Yaw, while its body flaps controls its Roll. After its speed slower than Mach 2 at 10000m altitude, its primary wing would retract and it uses its primary wings to land.

Its primary wings uses thick and low-speed airfoil in order to reduce its approach speed.
Primary wings 45 degrees sweepback for stability.
Because its upper wing surface does not Stand high pressure and high temperature, its upper wing surface could be made from Polymethyl methacrylate (PMMA) as a solar panel similar to the Soyuz spacecraft.
Its payload area is around its cockpit, its main fuselage is used to store rocket propellant.

It has a capability of recycable Serving as the second stage of 2300-ton Recycleable Saturn V Modernized Improved Combined Stage.
Its space is similar with Gemini spacecraft.
Its LEO Performance is generally estimated to be no less than 60 tons of LEO capacity on the shoulder of a 3000-ton first stage.

LEO Estimate: about 60 tons capacity, crew:0.
Could be launch on the shoulder of 2300-ton Recycleable Saturn V Modernized Improved Combined Stage.

TO Weight with propellant: about 500,000kg.
TO Weight with First stage: Depend on first stages, about 2700,000kg in total at takeoff.
Empty Weight: 60 tons estimated.