Penguin, despite your figures earlier in the thread, I don't think it's so far fetched that you could shoot down an RC airplane with an airsoft gun, provided a couple of conditions are met...
a) the airplane would probably have to be flying not much further than 50ft from the shooter
b) the airplane would probably have to be made of foam or maybe with a balsa frame or a similarly strong (or I should say weak) material
c) you'd have to have a couple hundred rounds to throw out

I have no doubts that an airsoft gun would rip an RC plane up under these conditions.
There's a few issues with trying to apply an airsoft gun for this purpose, all of which trace themselves back to the projectile;
BB's are spheres, which are decidedly unaerodynamic shapes.
An airsoft BB is large and made of plastic, so that it transfers little energy on impact, and over a wide surface area (as to not penetrate the target).
Since airsoft BB's are large, not very dense, unaerodynamic objects, they don't fly all that well, are easily affected by the wind, and don't have that much range, especially if the range you're measuring is that at which it can actually do damage to its target (which we are in this case).
Of course now you're throwing in a moving target, which drew me to the criteria above.
Now, if you'd like some real numbers, listen up

Brought the camera and gear out today (mainly because I wanted to see if my chronograph still worked and re-sight in my gun... and take some purdy pitchers), with the intention of recording some numbers for you and demonstrating what is realistically possible...
First off, testing materials...

Madbull Chronograph, AE .25g BB's (the 25% increase in weight over a standard .2g is worth it

), full can of Diet Pepsi (real men drink HFCS!) camera (not pictured, mainly because it's taking the picture

), LCT AKS-74, and a couple of magazines of BB's.
The chronograph is designed with this purpose specifically in mind so it has some fun, useful functions. First we have FPS and M/S (respectively). Colors are manipulated because my camera doesn't seem to like LCD's.


Then rate of fire in RPS and RPM respectively.


A nice thing that this chronograph does, as it's purpose designed for airsoft, is allow you to select BB weight, and the chronograph will take that weight and the speed measurement and convert it into joules, giving you a measurement of the energy of the BB at the muzzle. You can see what I mean by low energy of an airsoft BB, IIRC a paintball carries something like 16-17 joules of energy at the muzzle.

These are pretty standard figures for a mid to high end airsoft gun, with exception to the ROF because I have a crappy motor in it.
Now for some tests that look a bit more meaningful than some numbers... watermelons are to R. Lee Ermey as aluminum cans are to me. If you've never watched Mail Call then you don't deserve to understand what I mean

There's not much more fun than blowing up a full can of soda, and since the results seem to be more explosive (nyuk nyuk) with more power going to the can I shot it from only 6 feet away... however my AK is capable at penetration at much further distances.
'Look at him squirm'

Seconds later...

I should have video taped it... it's actually pretty entertaining

All of the soda is gone instantaneously... nothing but residue is left in the can. It's really cool.


Next I set up 45 feet away & fired about 15-20 shots. I really should have done this with an empty, but pristine can as the results are more useful; with the can split like it was, there's a lot more give in the aluminum and the BBs ricochet a lot more. You can see, however, where a couple of BB's found their way through the split, and hit an area of the can that was more or less intact; they had no problem making their way through.

As much as I'd like to try this with a plane I don't own an RC aircraft. It would be pretty fun, though
