In order to become a crew chief you must first decide what type of chief you want to be. Crew chiefs are important managers of people and equipment in the military, auto racing and on construction sites. Each job requires almost completely different skills and responsibilities. The one thing that doesn't change from job to job is that crew chiefs are excellent personnel managers with a lot of technical knowledge.
If you want to become a crew chief in the Army, you must be prepared to learn three different jobs. The primary responsibility of crew chiefs in the United States Army, for example, is overseeing a crew to repair and perform mechanical pre-flight checks on military helicopters. The second job of an Army crew chief is to be able to take over the gunner's job if he becomes incapacitated. Also, you must be able to fly the helicopter if the pilot cannot perform his duties. This means you need to research and work up the ranks not only to fix helicopters, but also to shoot their guns and fly them.
You don't need to juggle as many responsibilities to become an air crew chief. A crew chief in the United States Air Force, for example, is the person in charge of maintenance on various aircraft. An air crew chief needs to understand the mechanics of everything from a state-of-the-art fighter jet to a jumbo transportation plane in order to spot problems and get them fixed. People with a high aptitude for science, math and mechanics excel in this position.
An auto racing crew chief involves a much different collection of duties. You will need to have a sharp mind for mechanics, but you need to be even better at managing people if you are to be successful. If you become a crew chief for a race car team, you will oversee the entire crew and the driver, ensuring that the team has the best chance of winning. You also will report to the owner and sponsors, making sure they are informed and happy with the team's direction. Understanding the physics of racing and every single part of the car is essential, but so are your communication skills.
In order to become a crew chief on a construction site, instead of needing mechanical knowledge, you will need to know all about construction. You also must be an expert in handling personnel management because crew chiefs must oversee dozens or even hundreds of workers on a single project. You must make sure the project is being built on time and within its budget, so math skills are just as important as interpersonal ones.