I couldn't find sufficient info on this anywhere, so I was hoping someone might have some thoughts or insights on the topic.
From what I've read, maneuvering of the IXV within the atmosphere is performed by the two flaps and 4 thrusters. What I'm wonder is what kind of control authority the flaps can provide on their own. At the bare minimum, I would presume that they offer roll control, and perhaps nose pitch down, but is it possible that in conjunction with the lifting body shape that the flaps would be able to cause the craft to pitch up by reducing their downward deflection?
Most likely yes. However, if your angle of attack is positive with no active control required, the only degree of freedom that you actually need during reentry is roll control.
How much pitch control is typically necessary during the high-speed portion of the reentry phase assuming the pitch was correct at the beginning of atmospheric reentry? Is it not something that needs to constantly be adjusted?
And obviously you would want control if the craft performs a horizontal runway landing. I doubt the flap surfaces on the IXV would provide much control authority for pitching up at relatively low speeds (not that it can even do that, hence the parachutes).
My assumption is that you can rely on the shape of the craft along with its center of mass to naturally want to pitch up at certain AoAs, and use such rear-mounted flaps to manage its tendency to pitch up. Does that sound plausible?
I'm just curious about what the minimum requirements are for an RV of this shape, which can then revert to retractable rotors in autorotation for low speed control.