Aug. 19--If you're planning to get on an airplane between now and Labor Day, prepare for delays.
You won't know exactly when, but you'll know where: Logan International Airport.
As part of a $7.5 million repaving and reconstruction project, Logan officials said, they have to shut down one of the airport's two major runways for 40 hours this weekend. And in the following two weeks, there will be four more runway closings, two of them scheduled for 40 hours, and two that could last up to about 56 hours.
The hitch is they can't predict when the shutdowns will occur. They all depend -- literally -- on which way the wind is blowing.
Logan officials hope to avoid a repeat of the situation that occurred during parts of the first shutdown, Monday evening through yesterday morning. It ended up lasting 58 hours. The prevailing winds shifted to the northwest, leaving just two operable runways at times.
The situation contributed to an estimated 205 flight delays, many lasting 30 minutes or longer, a Massachusetts Port Authority spokeswoman said.
Victor Viktorov, a senior management consultant with Axia Ltd. in Boston, was returning from New York on the Delta Shuttle at 4:30 p.m. Wednesday when the pilot warned "there's some kind of runway stoppage in Boston, and they don't know why." Viktorov's flight landed about 30 minutes late.
Marlin Collingwood, a managing director with the public relations firm Bell Pottinger USA, said he dreads the two flights he has planned for next week, to Pittsburgh and Harrisburg, both in Pennsylvania. He fears runway shutdowns could delay him.
"I find Logan, on the whole, to be a little more reliable than other airports in terms of delays, but there never seems to be any rhyme or reason to when you do have trouble," Collingwood said. "It will seem like a perfect day to fly, and something will happen. This runway issue just adds to that angst."
The Logan project involves resurfacing and repairing lights along the 10,000-foot runway called 4R/22L, which sends departing planes over Belle Isle Marsh in East Boston or Castle Island in South Boston, depending on wind direction. It's one of five runways at Logan.
Massport spokesman Phil Orlandella said the construction plan requires shutting down the runway for three more 40-hour intervals, and two 56-hour intervals.
"When they schedule that all depends on the winds," Orlandella said.
Massport aims to have the work done by Labor Day, or soon after.
David Donbek, a senior meteorologist at AccuWeather Inc., which provides data to thousands of businesses and media clients, said predicting the prevailing wind direction 24 to 48 hours out is not that difficult at this time of year in Boston.
"Late summer tends to be more of a 'steady as she goes situation' than winter or spring, but there are always exceptions," he said.
Boston can expect so-called Bermuda high weather formations this month that would generate steady and predictable winds from the southwest, Donbek added, which would be optimal times for runway closings.
Planes can have problems taking off with a strong tailwind. When the wind direction shifts to the northwest, that can sharply limit use of Logan's second 10,000-foot runway, which aims planes southeast, over Boston Harbor.
Once Massport decides to shut down a runway, it has to keep working -- even if the wind shifts and begins threatening to cause delays -- because of the high cost of sending home construction crews.
Northwest winds became a problem Tuesday and Wednesday, contributing to about 155 delayed flights during an eight-hour period Tuesday and 50 more flights delayed during two hours on Wednesday.
Yesterday, runway work did not cause any delays, Massport said.
Construction crews will try to schedule the remaining work for periods when the winds are forecast to blow mainly or solely from directions other than northwest. Summer winds normally blow from the southwest. However, Orlandella said, "There's going to be some delays."
Given the amount of work to be done -- and the short stretch of time when northwest winds are most rare -- Massport concluded it could not do the work solely on weekends, officials said.
Officials at American Airlines and Delta Air Lines, the biggest and second-biggest carriers at Logan, ranked by passenger volume, minimized the impact of the construction work. They said they are confident travelers won't experience major problems.
Delta and American said they were reluctant to blame flight delays earlier this week specifically on Logan's runway work, given the way rainstorms or tarmac snarls in New York, Chicago, or Washington can cause ripple-effect delays for planes headed to Boston.
"Delta is expecting little, if any, customer impact during the few days the runway is under construction, and we are eager to see the project completed, as it will help us deliver on our commitment to a safe, comfortable customer experience," Delta spokeswoman Chris Kelly said.
American spokesman Ned Raynolds said: "We understand that the work needs to be done. We've had so many arrival delays for other reasons, so we can't say if any of those are caused" solely by the runway work.
Neil Bergquist, a Brighton pharmaceutical industry consultant who flies out of Logan two to five times a month, said his view of the inconvenience caused by the shutdowns is that "it really underscores the need to expand the runways at Logan."
After decades of battles with East Boston airport-expansion opponents, Massport this spring began construction on a sixth runway, called 14/32. It's scheduled to open late next year and will allow takeoffs only over the harbor, for smaller jets and private aircraft.
"Given the recent uptick in air travel, now more than ever there's a need to do it," Bergquist said.