(CNN) -- Percy von Lipinski figures he flies about 100,000 miles a year. He knows he's going to see a healthy share of flight delays regardless of where he goes.



A new study says delays will continue to frustrate fliers like this man at Washington's Dulles International Airport.



But he especially anticipates them at the larger airports, such as Chicago's O'Hare International -- "You can't possibly put that many planes there and not have a delay," he said -- and New York's John F. Kennedy International. So when he has a choice between two connecting cities, he said he'll generally choose the smaller one.



Delays at the larger airports, he said, are compounded by other hassles such as longer distances between terminals.



"There's wear and tear on your travel psyche -- which bus you need, which terminal you should be at," said von Lipinski, a 54-year-old Vancouver, British Columbia, resident who owns businesses around the globe. "By the time you get to your destination, you're bound to come up frazzled."



Delays contribute to that frustration, and there may be more of it to go around these days.



Though the percentage of delayed U.S. flights has dipped recently because fewer planes are flying during the recession, there's been a 20-year trend of increasing delays, and the increases should continue once economic growth returns, a study released Thursday by the Brookings Institution said.



The average length of U.S. flight delays rose from 40.9 minutes in 1990 to 56.5 minutes in June 2009, according to the study, "Expect Delays: An Analysis of Air Travel Trends in the United States."



It also found that among delayed flights, the share of those that landed at least two hours late more than doubled from 4.3 percent in 1990 to 10.1 percent in May 2009.



And in a 12-month period ending in June 2009, the majority of delays was concentrated in 26 metropolitan areas, or hub cities, the study said. Of these 26 hub cities, six had worse-than-average, on-time percentages for both arrivals and departures: New York; Chicago, Illinois; Philadelphia, Pennsylvania; Miami, Florida; Atlanta, Georgia; and San Francisco, California.



The nationwide on-time arrival rate was 78.9 percent, and the departure rate was similar, study co-author Robert Puentes said. New York's on-time arrival rate, 66.3 percent, was worst in the nation, said the study, which analyzed air travel between metro areas rather than airports.



Delays are going to get worse, study co-author Adie Tomer said.



"On-time performance has improved recently because the number of people flying is at its lowest point since 9/11, but as the economy bounces back, air passenger levels will grow, and on-time performance will likely resume its decline."



The hub cities that did better than the national average for both arrivals and departures were Salt Lake City, Utah; Phoenix, Arizona; Detroit, Michigan; and Washington.



The study said on-time performance generally decreases as air travel increases. In 1990, with more than 400,000 domestic passengers nationwide, the country's on-time flight percentage was just under 80 percent. In 2007, with nearly 700,000 domestic passengers, the on-time rate was around 74 percent.



The authors recommend Congress and other authorities use the findings to help decide where to invest in high-speed rail projects and other measures to ease airport congestion.



Michael Boyd, president of Colorado aviation consulting firm Boyd International Group, is critical of the recommendation, saying the country could handle the current flight demand -- and cut delays -- by improving its air traffic control system.



The old system, he said, is outdated, doesn't use all of the sky and directs planes to fly farther and longer than they need to.



"Instead of saying, 'Let's get a system that can handle the traffic,' Brookings wants to lessen the demand. That's a caveman mentality," Boyd said.



Deron Lovaas, transportation policy
What does the study's author recommend What does a frequent flier advise whenever possible? What are major city hubs What does a frequent flier recommend
Congress and other authorities use the findings to help decide where to invest in high-speed rail projects and other measures to ease airport congestion. when he has a choice between two connecting cities, he said he'll generally choose the smaller one. New York; Chicago, Illinois; Philadelphia, Pennsylvania; Miami, Florida; Atlanta, Georgia; and San Francisco, California. choose the smaller one.
question: What does the study's author recommend, answer: Congress and other authorities use the findings to help decide where to invest in high-speed rail projects and other measures to ease airport congestion. | question: What does a frequent flier advise whenever possible?, answer: when he has a choice between two connecting cities, he said he'll generally choose the smaller one. | question: What are major city hubs, answer: New York; Chicago, Illinois; Philadelphia, Pennsylvania; Miami, Florida; Atlanta, Georgia; and San Francisco, California. | question: What does a frequent flier recommend, answer: choose the smaller one.