Chapter 3
Stacks

Eisenhower began his last two years as President.   Legislation brought forth research funding for the Federal Aviation Administration, particularly in Air Traffic Control.  The FAA inherited a former military base near Atlantic City, a ragtag complex of pale-green barracks and crabgrass lawns.  It was named NAFEC for National Aviation Facilities Experimental Center.

NAFEC needed computer consultants and contracted with my company (TRW).  I needed the down payment for a house and accepted the offer, which included per-diem.  Besides, the assignment involved aviation, didn't it.

"Your assignment," said Henderson, while shaking my hand, "is to get rid of the stacks."

There was more to the air traffic control problem than that, but at the time I did not know it.  I had just arrived at NAFEC that afternoon from Harrisburg, my last overnight stop in an exhausting four-day drive from California.  The family Ford, loaded with dishes and linens and baby furniture, drooped in the parking lot outside the clapboard building.  On Saturday, my wife and our two infant children would be arriving in New York aboard a Boeing 707, one of those new-fangled jets.  The first member of the technical team on the scene, I had hoped to spend the first day looking for a place to rent.  Then I was introduced to Henderson.

My work at TRW was in the earliest applications of computers in process control systems for chemical factories, oil refineries, and nuclear reactors.  "What are stacks?" I asked wide-eyed.

Henderson shook his head and led me into a makeshift conference room.  There he erased a corner of the blackboard and lit up a Lucky Strike.  He was the first of many air traffic controllers with whom our research team would collaborate for the next year and a half.  I noticed the tiny blood vessels that marked the whites of Henderson's eyes, possibly the consequences of his years spent riveted to a radar screen.  He was forty or so, half again my age, balding and gray -- like the others at NAFEC, mostly gray.  Trying to be patient now, Henderson explained the "four-minute holding pattern" to his new associate.

"We simply have to get rid of them," he concluded.  "Stacks are the main cause of delay in the terminal area.  Now, you computer guys are supposed to help us figure out how to do that."

"Terminal area?"

Henderson tapped ashes into his palm.  "That's the controlled airspace near airports."  He drew diagrams and assailed me throughout the afternoon with an explanation of the structure of the airway system.  He laced the tutorial with plenty of his own opinions and priorities.

"Forget the 'enroute centers,' " he said at one point.  "There are 26 of them around the country, controlling planes on the airways between airports.  They just think they have conflict problems.  No comparison with what you get in the terminal area.  Sure, I know all about the Grand Canyon.  They didn't have radars then.  Enroute guys have plenty of time and space to play with.  They can vector the bastards all over the sky, if they want to."

Henderson was warming to his subject.  "Even in the terminal area, departures are not a problem at all," he went on.  "You don't need stacks.  If there's no room up ahead, you hold the planes on the ground, see?  The sons-a-bitches may not like that, but at least you're not stacking 'em up in holding patterns for separation.  After take-off, the blips stay away from each other anyway, simply because their flight paths..."  Henderson gestured, hands sweeping outward.

"Diverge," I prompted brightly.

"Spread out," Henderson grumped.

I loosened my tie.

"The real problem is 'approach control.'  It's the pressure cooker," said Henderson with finality.  "That's where you have the damned stacks.  Planes comin' at you from everywhere.  No place to put 'em.  Fast ones, slow ones.  You ever been in a radar room?"

I shook my head.

Henderson sighed.  "Better get you up to Idlewild, first chance.  Those poor sons-a-bitches got it tougher than anybody.  They got weather, they got satellite airports: La Guardia, Teterboro, Floyd Bennett, Roosevelt Field...  Jeez, and half the pilots that fly in there don't even speak English.  And stacks?"  He sketched a map.  "We're talking about Idlewild, here.  There's a stack called Lido up on Long Island -- forty, fifty miles away.  Also, Point Pleasant down in Jersey.  Six -- sometimes eight -- planes holding in each one.  We don't need computers to tell us: gotta have more runways.  Hell, you'll see."

Many of the people I would meet at NAFEC came out of the military.  Henderson had been a fighter pilot in WWII.  I never learned his first name, nor he mine.  For some reason the man had not joined an airline.  Right away, I admired Henderson, in no small measure because of his status as a former wartime aviator.  Later, though, I observed that the combat stories he spun related only to the experiences of other pilots.

None of the controllers assigned to the research projects at NAFEC had technical backgrounds.  They were GS13s and made no effort to conceal their disdain for the young, overpaid technocrats who, when it came to understanding air traffic control, "couldn't find their ass with both hands in three tries."

It was true that none of the members of our company's research team had any previous experience in aviation.  Numbered among the seven of us were mathematicians, engineers, and physicists -- but no pilots.  As for my two measly solo flights in 1957, I found no occasion to mention them.  The FAA chose our company for its reputation in real-time control computers, skills newly honed in the fledging space program and applied in the process industries.

Directing airplanes in the sky, we soon learned, was nothing like controlling a chemical plant.  Still, computer technology was in its infancy, and so, too, was air traffic control,   I was chosen partly because of my research at UCLA in vehicular flow problems.  The official assignment for the TRW team was to design and build a huge man-machine simulator for testing technologies and procedures in the terminal area environment.

From our point of view, NAFEC was an earnest but ill-equipped operation.  The FAA, it seemed to us, had looked around the country and found this hapless bunch of burned-out controllers.  Nobody could figure out what to do with them.  So they sent them down to Atlantic City, made them instant experts, and told them to guide the research.  It was, we would mutter among ourselves, like sending dirt farmers to design tractor engines.  For the controllers, though, NAFEC was good duty.  Low pressure and lots of ego in it.

Initially, for example, none of us technical types from industry knew a "dog-leg vector" from our elbow.  That made for some sport.  Imagine the chortling by our mentors when we came along later and proposed an improvement in dog-leg vectoring procedures which benefited from "geometric properties of the isosceles triangle."

Many of our research recommendations were rejected out of hand ("You will never get the airlines to accept speed control").  Others became sidetracked through the inability of our counterparts to generalize from the particular ("What'll you do with the Lockheed Electra following a DC-3?").  Our contract provided no channel of appeal to a comprehending authority.

The air traffic controllers assigned to work with us, well-intentioned as they were, had little respect for the scientific method.  That was undeniably the most worrisome aspect of the FAA sponsored research. It was soon to become clear as hell.

"Like I say, stacks are the main cause of delay in the terminal area," said Henderson, clapping the chalk dust from his hands.

"Cause?" I queried.  "Or effect? -- of not having enough runways, I mean."

"You put a plane in a stack and you're causing delay."

"But that's the point, isn't it." I protested.  "Seems like the stack is merely a necessary evil.  No matter how many runways you have, won't you still need places to store airplanes in the sky? -- to accommodate periodic surges in traffic volume?"

Henderson pinched a flake of tobacco from the tip of his tongue and grimaced.


 
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