The Federal Aviation Administration (FAA) requires that, in the event of an emergency, all airplane passengers must be able to evacuate any aircraft within a 90-second window. But is that a realistic requirement, particularly given the increasing number of elderly passengers who might need more time and assistance? According to a new paper published in the journal AIP Advances, it is not. Various simulated scenarios showed evacuation times significantly higher than the 90-second requirement.
This isn't the first time scientists have puzzled over this kind of optimization problem. Back in 2011, Jason Steffen, now a physicist at the University of Nevada, Las Vegas, became intrigued by the question of the most efficient boarding method; he applied the same optimization routine used to solve the famous traveling salesman problem to airline boarding strategies. Steffen fully expected that boarding from the back to the front would be the most efficient strategy and was surprised when his results showed that strategy was actually the least efficient.
The most efficient, aka the “Steffen method,” has the passengers board in a series of waves. Field tests bore out the results, showing that Steffen’s method was almost twice as fast as boarding back-to-front or rotating blocks of rows and 20–30 percent faster than random boarding. The key is parallelism: The ideal scenario is having more than one person sitting down at the same time.