Dr. Ki-Hwan Bae on the logistics of Flight Planning

June 5, 2017

Headshot of Dr. Ki Hwan Bae

Consumer expectations for the return on their hard-earned dollars can prove a logistical challenge, especially for industries like supply chain, delivery, or transportation. Dr. Ki-Hwan Bae, an industrial engineer in the University of Louisville J.B. Speed School, is one of many professionals who work to make sure that the needs of both consumers and businesses are balanced and met. Bae specializes in operations research, a field of study that looks at mathematical algorithms for improving systems by working with simulations. His dissertation was on airline scheduling problems, an issue that remains elusive and difficult to manage.

Looking at the physical logistics alone, most airlines operate out of a hub and spoke system, where specific airlines have hubs of activity relative to a particular city. The spokes connect the hub flights, which serves as a central processing system. Airlines have to balance passenger demand and flight size, service issues for the vehicle, the needs of the crew, and any potential weather hazards that may pop up sporadically, all in the context of organizing around centralized locales.

“Sometimes airlines need to dispatch crews to provide continuous flight service,” says Bae of a further complication to scheduling, “We call that dead heading crews. The crews are dispatched, maybe as a substitute for available pilots, maybe they’re sick, and then brings that plane back to provide continuous service.”

The Airline Deregulation Act of 1978 ushered in practice like deadheading, in a bid to make the open the industry up to the free market. The act offered up leniency to airlines, which previously suffered stiff restrictions on when and how passengers could travel. The result was an increased number of flights and lower fare.

“The devil is in the details. The class code, within the economic class, business class, etc., it comes with different restrictions. For example, if you and I buy a ticket from Louisville to Chicago on United, but you may have paid $300 and I paid $500, it dictates what you can do. Airlines do that, because they want to maximize revenue. It’s called revenue management,” says Bae.

It’s all about balancing the many obstacles put to airlines with their bottom line. Airlines have system that is easily upset with weather and circumstance, but which they’ve evolved to try and work around.

Bae explains, “They have a sophisticated system. If the demand is really growing, say they come up with a seat, for a certain class, for a certain seat, if the demand is good, then they will increase that (cost) dynamically. If the demand is high, they will decrease that (cost) for that seat class. If the demand is low, then they will relocate that seat to someone who’s lower. Depending on when they booked the flight and when you book.”