Airplane question! (Manuevering Speed and Weight)

Ok, so I've been trying to figure it out why Va (Maneuvering Speed) decreases with a decrease in weight, and this is what I came up with:

At a higher weight, Va is higher, because the plane is already flying at a high angle of attack, that a sudden full deflection of the controls wil cause the plane to stall before any structural damage is done to the airframe, while at low weights, since you're flying at a much reduced angle of attack, there is a greater possibility that you will do structural damage to the aircraft before you stall the plane.

So, am I right, or did I miss the barn?

I'm desperate for an answer, and I don't know who else to turn to...

Va (maneuvering speed) is defined as the speed at which full deflection of the control surfaces are prohibited to prevent structural overstressing of the airframe.

Stall is defined more or less as when the centre of pressure on the wing (where all of the aerodynamic forces act through) moves sufficently forward on the wing as to cause a sudden cessasion of the production of lift - rendering the aircraft unable to maintain level flight.

Angle of attack is defined as the angle that the wing (chord) makes with the relative airflow. Most wings stall between 12-15deg.

Jam it back in, in the dark.

I'm not an aviation expert, but I'm going to try attack this with a simplified physics example though I just may end up looking like an idiot since both areas aren't my strongest points.

Say you are driving a car with 1 person in it and you go over a bump. The car is going to bounce and the structure of the car is going to be under a lot more stress from the increased 'up and down' motion from the car frame bouncing.

Now consider the same car and load it up with 10 people. Going over the bump is going to result in almost no bounce and the cars frame won't be effected from the stress of the car bouncing up and down.

I imagine a plane in the air follows the same basic principles. A heavy plane isn't going to be effected by turbulent air as much as a light plane. Thus since the heavier plane isn't being tossed around in the air as much, the airframe isn't being subjected to such a high level of overall stress.

How ya doing, buddy?

So I've figured it out - if anybody is interested, here's an explanation:

First of all, we have to look at the effects of weight and g-forces on stall speed. As weight increases, so does the stall speed, because the wings are required to produce more lift to counteract the weight and remain in level, unaccellerated flight (all forces balance each other, lift and weight, thrust and drag). During a turn, or an abrubt climb, the g-forces also increase, which effectivly increases the airplanes weight (2Gs would double the aircraft weight). Hence, with an increase in g-forces, stall speed will also increase.

From this, we can determine that at higher weights, the aircraft will stall (elimating the largest force on the structure, lift) before the increasing g-forces will cause structural damage.

Cetra is also partly correct, inertia plays a big role as well. Heavier aircraft resist changes in acceleration more then lighter aircraft do. How it was explained to me was like this:

Imagine two vehicles speeding on a highway, a sports car (light aircraft) and a truck (heavy aircraft). If they both try to make a sharp corner, the sports car is going to flip, while the heavy truck is just going to swerve.

This thing is sticky, and I don't like it. I don't appreciate it.