The F-21B is the second variant of the LJ Dynamics 21 series, and now has VTOL capabilities. It is carrier operable, in VTOL mode AND in normal flight mode. It can carry up to 200lb per pylon, and through that is not capable of heavy bombing. It uses the same 25mm cannon as the A variant. The four pylons are located under the fuselage, no longer under the wings. For maneuvering in vertical flight it has RCS nozzles on the wingtips of main wing and canards and in the back on each side of the engine exhaust. It also has two vertical stabilizers, in order to fit the engine, which rotates up, with the intake between the stabilizers. In vertical flight it uses two engines in front and the engine in the back. If necessary there will be following Blocks (versions/improvements) to improve the performance.

CONTROLS

AG-1: VTOL mode
AG-2: arresting hook
AG-8: RCS systems

FLYING:

For vertical takeoff, you cant just use full throttle, because it will almost immediately tip over, not being recoverable. You have to use 20%-30 prevent throttle, it lifts at about 18%.
In order to go on normal flight mode, you have to accelerate to at least 100mph GS, and then deactivate VTOL mode. If you want to make completely sure you don't stall, accelerate as much as you can in VTOL mode, and then after activating normal flight mode go full throttle.

For suggestions what I could improve for following versions, or have ideas for future variants, please tell me in the comments!