The other thing I'll point out is that you're talking about a plane at 36,000 feet and travelling at ~360mph. That tranlates to roughly 528 FPS. The speed of gravity is around 32 FPS, and that excludes any kind of drag that the plane may have which means it's likely that the plane will take longer than 36,000/32=1,125 seconds (almost 19 minutes.) This means that you can be talking about 1125*528/5280=112.5 miles that pieces of the plane could be dispersed PROVIDED the ocean currents don't do anything to it, there's not any drag on the pieces that slow their movement down, the plane lost power 100% in the mean time etc. I'm probably botching the math on this a horrid amount but the point is if they just dropped out of the sky 19 minutes is a long damn time for something to happen when you're moving at 360 mph.
WARNING!!! Boring physics content below!!!
I had a somewhat challenging time understanding part of your post, but I think it alludes to the potential for the debris to be spread across a large area. That assumes that the plane was breaking up in mid-air. Your physics math is pretty far off though. I can see where you were going, but you made an error with the unit of measure of your 32fps gravitational free-fall figure. Remember that earth's gravity accelerates objects falling at a rate of 9.8 meters per second squared (-9.8m/s^2) or 32 feet per second squared. So, in the initial second of falling towards earth, assuming zero drag, it would fall roughly 32 feet. However, that's just the first second of falling, it will continue to accelerate to a velocity beyond what the initial first second exhibited, and so on until it reaches terminal velocity due to aerodynamics. Remember that there is a large difference between acceleration and velocity. This also doesn't take into account that the plane's direction of natural aerodynamic travel will point from the tail and towards the nose (aka, the plane would fly like a dart). Because of this tendency for it to fly like this, you would also have to take into account the plane's starting forward X axis velocity of somewhere around 600-700mph (international flights usually travel that fast in my experience). So, this initial velocity would propel the plane even faster towards the ocean if the engines suddenly lost power and the pilot could not pull out of a dive.
So, physics math below!
V^2 = Vo^2+2ay, when V=final y axis velocity, Vo=initial y axis velocity, a=gravity, and y=total fall height
The final velocity right when an object that falls from 36,000'(10,972m) is actually right at 464m/s (1,522fps), assuming zero drag, which is obviously not the case in the real world, but we will keep this simple for the sake of argument.
The total fall time would be computed using:
V = Vo+at, when V=final y axis velocity, Vo=initial y axis velocity a=gravity, and t=elapsed time.
Using that formula, the total fall time for an object free-falling from 36,000feet, assuming no drag, would be only 47.3 seconds. That's a lot quicker than your estimation of 1,125 seconds. Yes, this doesn't factor in drag coefficients, which would be immense, but it also doesn't factor in the "dart flight" tendencies of the plane coupled with its initial forward velocity either. So, for simplicity sake, we will call that a wash between the two.
In short, if a plane lost power, and somehow could not glide for a while/otherwise just sort of plunged in a parabolic downward dive, theoretically it could fall to Earth within less than a minute. That means that there may not be a large area across which debris could be initially spread. Still, since junk likes to float, I would think there should be all sort of cushions, plastics, etc floating in the ocean afterwards.