(CNN) -- Every day 1,300 aircraft pass through London's Heathrow Airport. Making sure all those planes are in the right place at the right time is the job of the aircraft marshal.
We've all seen aircraft marshals at work, standing in front of an airplane as it prepares to park, waving their arms in apparently random directions like they're leading an aerobics class.
But what does all that arm waving mean? And what if you had to step into an air marshal's shoes, would you be able to park a plane? Take the quiz above and find out if you've got what it takes.