Anybody who’s seen the movie “Top Gun” has a clear image of the pilots slipping into their cockpits like a hand into a glove. It’s not by accident; the U.S. military has focused for years on designing cockpits that accommodate the pilot population and maximize their effectiveness. Today, we discuss a project that is also focused on airplanes, but not on the cockpit and the pilot. Instead, our fundamental task was to make sure the maintainers, who work on the planes, could fit well within the aircraft’s mechanical compartments, and could reach and manipulate the thousands of small parts that work together to make the plane so powerful.
Airplane designers have historically paid most attention to the cockpit of an airplane because that’s where the pilot sits. The planes’ maintainers, who regularly perform work on the airplanes when they are grounded, were hardly if ever considered. While pilots are mostly similar sizes – slim and not too tall – maintainers come in all shapes and sizes. Because the access points on many airplanes were not tailored to the larger maintainers’ frames, some maintenance workers could not fit within the area they needed to reach in order to perform work.
In 2000, we were approached by the United States Joint Strike Fighter (JSF) program’s multi-service initiative (which includes the Navy, Air Force and Marines), to address the problem. Leaders wanted the next round of aircraft designs to take into account the dimensions of the maintainers as well as the pilots. By this time, they were using CAD and digital human models (i.e. computer mannequins) to design airplanes, so our goal was to identify the dimensions of a set of computer mannequins that represented the body size range of the group of people who maintain the airplanes. The JSF human factors team could then create digital models based on those dimensions and put the models into computer mockup systems to make sure the maintainers could reach and work in the areas they needed to.
How Anthrotech Helped
Unlike many projects where we are building a database from scratch, we didn’t have to do any measurements for this project. We were able to utilize measurements from 1,450 people already in our ANSUR database (which is short for “anthropometric survey”; this database represents the 1988 Anthropometric Survey of U.S. Army Personnel).
We derived the dimensions of the finished mannequins so military leaders could create any number of different computer mannequin packages. We used Principal Component Analysis, a statistical technique previously used to create pilot cases, to combine many different dimensions to accurately characterize the maintainer population. We then identified sets of dimensions on the periphery of the distribution to represent, essentially, uncommon combinations of body measurements. The theory was that if a plane could be designed so that these uncommon individuals could maintain it, then the rest of the maintainers who are more typically sized could certainly also do their jobs within the space.
Planes based on this work are now being produced by Lockheed-Martin. These aircrafts will be utilized by the United States and its allies around the world, and they will accommodate not just pilots, but also those important folks who keep the planes working safely in the air, thanks in part to Anthrotech’s contribution.