United Airlines
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The disappointment that comes when you run through the airport only to realize you missed your connecting flight by a matter of minutes can be painful. And it might not seem rational – especially if there are other passengers and checked bags involved.

The reason behind strict gate closures is to obtain high “D-0” (D-zero) rates. The D-0 metric designates flights that depart on time and is monitored by the industry to evaluate airlines.

United Airlines is working on alleviating this issue by testing out a new program, named “Dynamic D-0,” at their Denver hub, that uses a new software to evaluate several factors to determine if it’s possible to hold a flight. Since about a quarter of United’s flights arrive at least 10 minutes early, the software examines these flights, then takes into consideration the list of connecting passengers to determine if there’s room to delay the departure time. United’s operation center then identifies flights with departure flexibility and alerts gate agents.

United president Scott Kirby said at an investor conference that this new software can see, for example, "here's five or six customers that are coming to this connection; they’re going to be five minutes late, but we know we can make up the time in flight on this particular flight.” However, he warns that sometimes holding the plane won’t make sense.

While still in its test phase, Dynamic D-0 has already saved thousands of connecting passengers from missing a flight. United is planning on rolling out the software at other large airports later this year, eventually using it for every flight. These calculated flight holds are expected to have “minimal impact on performance as the flights are expected to arrive on time, even with the hold,” explained United spokesperson Erin Benson.

Next time you run through the airport to make a connecting flight, consider yourself lucky if you’re flying United.