Taking an airplane flight today is quite common. Literally millions of people board an airplane each day, traveling to virtually every part of the globe. Some will find their ride slightly uncomfortable, because airplane seats are a little smaller.

The average airplane seats measure 17.2 to 18 inches across (43.68 to 45.72 cm). This means anyone with more than a 36 inch (91.44 cm) hip measurement is likely to feel a little squeezed upon sitting down. There are some exceptions. Midwest Express, for instance has a 21-inch (53.34 cm) seat width. First class and sometimes business or executive class flights may offer wider seats.

Some airlines insist that airplane seats measurements have not changed. It is true that North Americans have changed in size. There are now more people who need the extra width, and some for whom this width will still be very uncomfortable.

Another, and perhaps more crucial difference in airplane seats comes from the measurements between seats aligned vertically. This measurement, called the pitch, has changed considerably. While we are also a bit wider, we are also considerably taller. Much discomfort in long flights comes from the inability to move one’s legs properly due to small pitches.

In first class airplane seats, pitch is seldom an issue. Most have a generous 80-inch (203.2 cm) pitch. On coach or economy class planes, pitch tends to be about 31 inches (78.74 cm). Some companies offer a larger pitch of 33-34 inches (83.82-86.36 cm). Boeing, in fact, has standardized a 33 inch (83.82 cm) pitch for airplane seats in its 777s. Smaller planes are likely to offer the smallest pitch, and international flights the largest pitch.

In all, however, pitch is still by many accounts too small, which in turn makes airplane seats feel too small. A person over six feet (1.82 m) tall, with hips wider than 3 feet (.91 m) is likely to feel squeezed both vertically and horizontally on the smallest airplane seats with the smallest pitch. Anyone who has had the experience of having one’s seat kicked by a small child in a seat directly behind one, will also realize that smaller pitch makes this possible.

Airplane seats are often criticized because adding more seats to a plane often means reducing pitch. Even when a plane is only half-full, pitch is still likely to cause discomfort on long flights, and perhaps on short flights as well. Some companies are attempting to increase pitch, but this then leads to greater ticket prices, because the same amount of fuel transports fewer people.