(The second in a three-part series, by SCAA Board Member Chas. Talbot, examining the proposed third runway at Sea-Tac Airport.  Last issue, the case for looking for a second regional airport;  next issue, environmental issues, and conclusion.)

The Port of Seattle, owner-operator of Sea-Tac Airport, has two simple explanations of the need for an additional, 8500-foot runway, to be built 2500 feet west of the present main runway. One explanation is that this new runway, to be used for arrivals only, will eliminate - or at least reduce - costly delays in flying into the Airport during bad weather. The other explanation is that the new runway will increase "capacity";  that is, handle more airplanes, more passengers, and more freight.
Some bad weather closes the airport entirely. Flight-safety rules require that in other bad weather, aircraft stay farther apart upon landing than during good weather, which reduces capacity. The new runway would allow closer spacing, but it is still too close to the other runways to permit the same rate of landing in bad weather as in good.
In all the planning documents and in the lawsuits, the Port, its experts, and its lawyers (joined by the local FAA) have steadfastly asserted that the future capacity at Sea-Tac will be the same with or without a third runway. Therefore, they say, there will be no new environmental impacts - no additional noise, no new air pollution, no additional ground traffic - as the result of the third runway. In this way, based on their "best professional judgment", the two agencies avoid any discussion of future environmental harm.
However, to the general public, and especially to business-oriented audiences, the Port tells a different story: the runway is needed to accommodate additional traffic in the future, so that it would be used both for landings and take-offs, which would not be possible without the runway - an exact contradiction of what it told the State and Federal courts. The Port says that unless the Airport provides for those additional flights, the result will be devastating to the local economy. As a corollary, the Port argues that airports are a major creator of

non-aviation jobs. As a second corollary, the Port argues that it has the only airport (or site) in all of Western Washington that could possibly be used for ordinary commercial traffic. Each of the Port's arguments has a grain of truth.
"Delay" costs airlines and travelers money, and Sea-Tac says that some time in the future, these delays will amount to hundreds of millions of dollars every year. Building new runways costs money, too, and it's the same airlines and travelers who pay the bill, so a careful needs-benefit analysis is needed.
As to need, Sea-Tac is not measuring delay as is done for almost all other purposes.  Ordinarily, "delay" means that a plane arrives or departs 15 minutes or more after the scheduled time. But to justify the runway, the Port says an aircraft is delayed if it arrives even one second after the scheduled touch-down. It is also said that travelers' time is worth $40-plus per hour.   For this, we need a $773 million dollar runway, the most expensive ever built in a non-marine environment?
Delay is more expensive to airlines than to travelers. There would be a slight gain in efficiency from a replacement second runway. However, the cost benefits are grossly overstated, and several major airline users reject the proposal on that ground. And a large part of the delay problem is actually caused by unsound scheduling. Especially at peak periods, some airlines consciously schedule many more arrivals and take-offs than airports can handle -- and travelers cheerfully go along with the gag.  The Port has great trouble

in explaining how many flights in its survey were delayed just because of bad weather at Sea-Tac. What about delays at the point of departure? What about delays because departing airlines are held on the ground here because of problems at destination airports? What about bad weather en route? What about problems with the nation-wide air-traffic-control system?
And it is true that air traffic continues to grow (see figure below). However, if traffic grows as projected, Sea-Tac will soon run out of everything - air space (shared with King County International Airport), runways, gates, terminals, ground access, and level ground to build on. There will be delays from many causes, and the more activity that is crammed into the site, the worse the problems.
And, finally, we agree that airports are a necessary part of the infrastructure for a modern society. However, industry is not created by infrastructure. Look at Moses Lake, with the longest runway in the State, and over 300 days of good weather per year. Where's the industry created by that runway?  It's industry and people first, then infrastructure.
Long before delays become so intolerable that it's worth $773 million for a partial solution, common sense will take over. The brighter airline executives, and savvy travelers, will use other facilities, some already in existence, some yet to be developed in response to market demand.  And, if the airlines cannot figure this out for themselves, why should the public pay to bail them out of their jam?