Airport capacity is usually referenced as ability to handle xxx passengers per year (usually in terms of millions of pax). It seems that the more relevant figure and limiting factor would be the # of passengers per day that the airport can handle. So why is an annual figure used and how is this number determined?
I suspect annual numbers are used because that is what the annual report is based on. Capacity is some vague number based on the number of gates, the size of the airplanes that can use each gate the number of check-in counters, baggage carousels, nighttime curfews etc. Or somebody with a fresh MBA says each passenger takes up 2.9850769 square feet and will be in the terminal an average of 73.2 minutes therefore this airport has a capacity of xxxxx. (per year)
porterjet - FlightAware user avatar
Joined: 17 Jan 2006 09:00
I suspect annual numbers are used because that is what the annual report is based on.
But it seems irrelevant how many passengers can be moved through an airport in a year. All of the condtraints that you listed, including how much square footage each passenger would occupy are related to the daily throughput of the airport which would seem to be a much better gauge on whether the airport is correctly sized to handle the passenger flow than basing it on the total # of passengers for a year.
If an airport has 100 toilets but there are 300 people who need to use them at the same time, then it matters not that tomorrow there may be only 20 people who need them- as for today- the airport is over its capacity and THAT is relevant to those pax waiting for a seat, be it in an airplane, on a toilet or in the terminal. And these daily factors would be much more indicative of how the airport is handling its traffic.
Businesses and politicians typically only think in long term averages, one day variations don’t count. The difference between a daily average or a yearly average is just math.
I understand what you are saying but the board of directors will only pay to build an airport based on a yearly average, they are never ever going to fund an airport based on the number of passengers forecast for day before Thanksgiving. Let the people cram themselves in on those one or two record setting days and stand in line for the toilets, the rest of the year will be fine, and more importantly something the city or county can afford.
Keep in mind the capacity numbers you see are not the absolute maximum number of passengers that can fit inside the building but one where the architect says “this many can fit comfortably and still be served in a reasonable manner.” You see airports operating over the original design capacity using little fixes for decades before the politicians can come up with the money for a major expansion. When the line for the toilets gets to be too long, everyday, then the politicians will act.
Look at our freeways, they are always 10 years behind what is needed today.
Part of the reason for not using daily numbers is because it is constantly variable. Certain days of the week may be dead, while others are extremely busy. Throw in a holiday or special event, such as the Super Bowl, and any average you come up with won’t matter.