There is an extremely serious design issue that continues to plague the travellers of the world. I estimate that this problem has existed for centuries -- or at least since the invention of the armrest.

We often find ourselves sitting next to people. People we don't even know. Be it a bus, a train, a movie theatre, or any public place where seats are placed side-by-side. The "situation" I'm about to discuss becomes especially relevant on an airplane, where space is scarce, and sitting is a mandatory position for any number of hours.

It's about sharing. Something that the world has shown little interest in. It's also about the armrest, and how it's precious few inches of solid existence can be a war zone -- a battle between two elbows jockeying for position.

The problem

Taking a look at Figure 1, you'll notice how the scenario usually plays out (for me at least). My arm is shown in blue, while my neighbor's to my right is shown in green. My neighbor has taken up the entire armrest that's designed to be shared between the two of us. Rude? Yes. He or she gets the armrest, and I get nothing. I'm forced to sit as if I'm in a bobsled, with arms straight as an arrow at my sides.

Figure 1

Possible solutions

One solution (and there are a few of them) would be to divide the armrest in half (width-wise), where we each get to rest our elbows on the inside edges (Figure 2). This method works OK -- and if you have an elbow-conscious neighbor, this is usually what happens. Consider yourself lucky if you run into this scenario. But it's hardly ideal, with neither one of you getting a comfortable position.

Figure 2

But there is a better way -- one that gives enough support for each elbow. It just requires some clever geometry.

Dividing the armrest into equal halves (front to back), one person places their elbow in the front half, pointing their arm diagonally in towards themselves. The other person takes control of the back half in the same manner. There's now ample room for both -- each with proper support (Figure 3). The result is a Jenga-like interlocking of arms. A yin and yang at 30,000 feet. All it takes is some cooperation between the two passengers.

Figure 3

In a perfect world, each airline and bus company would have these diagrams attached to the back of every seat, right alongside instructions for using your seat cusion as a floatation device. The result would be ultimate harmony -- with no arm left behind. Consider yourself now an ambassador for armrest equality.