Ground surveillance system

With close to half a million annual takeoffs and landings on six runways, ground traffic at Detroit Metropolitan Airport can get hectic. To avoid collisions, the airport relies on a ground surveillance system provided by Sensis, a company in East Syracuse, New York. The system uses information from radar and transponders to give air traffic controllers real-time details on the locations of aircraft and ground vehicles. CEO Jud Gostin developed air defense systems for General Electric before founding Sensis in 1985. The 650-employee company has installed systems at 30 airports across the country, including Boston's Logan International Airport.

Safety vest

High-visibility vests are a must for airport ground crews, given that jet noise and protective ear coverings make it difficult to hear danger approaching. The bright-yellow color and reflective stripes on this vest, custom made for Delta by M.L. Kishigo in Santa Ana, California, help keep workers out of harm's way. CEO Loren Wall founded the company in 1973 and named it after his late wife, Mary Lou Kishigo. It has 95 employees and makes a full line of safety clothing for the construction, energy, and public safety industries.

Belt loader

Detroit Metro serves as many as 36 million passengers a year. Ground workers get bags on and off planes with the help of this belt loader made by Tug Technologies, a Kennesaw, Georgia, company that supplies equipment to more than 100 airports worldwide. The loader, essentially a conveyor belt on wheels, can be raised or lowered to accommodate various airplane heights. Tug, which was founded in 1972 by Jack Cordray and Howard Walkenheim, was bought by private equity firm Jacobson Partners in 2005. Now run by CEO Stefaan Ver Eecke, it has 170 employees and $100 million in sales.

Tow bar

Jet fuel isn't cheap. To cut consumption on the ground, planes are often pushed away from gates by tractors equipped with tow bars. The tow bar shown here was manufactured by Hall Industries in Ellwood City, Pennsylvania. The company, founded by Harold Hall in 1966, makes components for bridges and mass transit systems, in addition to aviation equipment. Harold's son, Jonathan Hall, took over as CEO in 1994 and runs the 150-employee business with his three brothers.