One other way to think of the Sukhoi/F22 etc. TVC is by drawing a vector diagram.
To pitch the nose up, the donks alter their axis of thrust giving a vertical component. Say, a 20 degree offset. Take an F22 at altitude producing 50,000lb combined thrust, that gives a vertical component of thrust (down) of about 17,000 lb which is countering lift, so is an extra "weight" to be borne by the wings. As far as the wings are concerned, the aicraft suddenly "weighs" 17,000 lb more.
50,000 lb gross weight, at corner velocity pulling 9G the airframe was producing 450,000 lb of lift. Add in TVC and it is now being asked to produce 467,000 lb of lift so something has to give - either G has to reduce (reducing turn rate) or the plane has to accelerate to produce the extra lift (also reducing turn rate). (Both in steady state, suddenly chucking in TVC would probably bend things!).
TVC also offloads the tail aero surfaces, reducing their trim drag and downforce... so it may end up all just cancelling out.
That's what thinking back to my Aero Eng tells me anyway!
Last edited by Deskscribbler; 18th Feb 2021 at 12:04.