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How do aircraft like the V-22 not tilt under an unbalanced load? if they are only supported by 2 forces on either side a large weight in the back should cause it to lean backward when stationary, should it not? its hard to put this into an image but here goes nothing:
A large weight in the back would surely cause it to lean; original image source
If you think about it, your question applies in exactly the same way to a conventional helicopter. You might expect that it would pitch nose-down if the weight is forward, and nose-up if the weight is aft. In fact, it's even worse for a conventional helicopter, because with only one rotor it would roll (tilt left-right) as well as pitch.
The answer is the same for the Osprey as for a conventional helicopter: the pitch is controlled by cyclic control of the rotor. As the rotor spins, a mechanism inside it changes the angle of attack of the blade (the pitch of the blade) as it rotates. This change can cause it to generate more lift when it's at the rear than at the front (or vice-versa, or left-to-right). This creates a turning moment about the centre of the rotor disk, which counteracts the moment of the unbalanced weight.
You only get so much of a moment with it, though. The aircraft needs that moment in order to change its pitch to manoeuvre. If you had to use the full range of blade pitch (the maximum cyclic control) just to counteract the unbalanced weight, you wouldn't be able to pitch the aircraft any further in that direction. For this reason, the maximum moment of rotorcraft (how far the centre of mass can be away from the centre of lift) is typically smaller than for airplanes.
According to various bits of online documentation, the rotors have cyclic pitch control like a helicopter as well as collective pitch control like a helicopter and most high-performance propeller airplanes (often referred to as having a "variable pitch" propeller). The cyclic on the Osprey is controlled with a swashplate that apparently has only front-to-back cyclic control since side-to-side is not needed. To move sideways, the Osprey would simply increase the collective pitch of one rotor while reducing the collective of the other. Here's a passage from one document I found:
Specifically by axis, pitch is controlled through longitudinal cyclic, lateral control is obtained through differential collective combined with lateral cyclic, and height control is via symmetric collective commands.
So it works like a typical helicopter and the lift can be adjusted as needed to deal with a variable center of gravity.
I suppose it could, if improperly loaded. But V-22s, like any other aircraft, have weight and balance envelopes to prevent this from happening. And any competent loadmaster and flight crew would load the aircraft accordingly and double check it prior to flight.
