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Weathering heights: Crane operator makes the climb for hospital expansion

Crane operator A.J. Barker climbs 200 feet each workday as he helps assemble the framework for the expansion of Lucile Packard Children's Hospital Stanford.

- By Ruth Schechter

About 200 feet off the ground, A.J. Barker spends his days at the controls of a tower crane “flying iron.”

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A.J. Barker might not have a long commute to work in the morning, but he probably has one of the highest.

Each workday, he climbs 200 feet of steel to position himself in the cabin of one of the two enormous, yellow tower cranes at the Lucile Packard Children’s Hospital Stanford expansion work site. He then spends the next eight or nine hours “flying iron” — moving steel girders and beams throughout the construction site and helping to assemble the framework of a new state-of-the-art center for pediatric and obstetric care. 

Sitting almost 16 stories in the air, Barker uses two handheld joysticks to maneuver the crane’s 267-foot working arm, or jib, into position, lowering a hook or coupling it into place, coordinating the connection, and then moving the object to the desired location — all while keeping an eye on the activity on the ground, other cranes, the direction of the wind, even the arrivals and departures of the hospital’s Life Flight helicopters.

“I have the coolest office view, and it changes all the time,” said Barker, who is working with a subcontractor to DPR Construction, the firm overseeing the expansion project. He is one of the more than 200 contractors, subcontractors, architects, and trade specialists building the hospital’s 521,000-square-foot addition. There will be 7,900 tons of steel in the entire superstructure when complete.

Sitting almost 16 stories in the air, Barker uses two handheld joysticks to maneuver the crane’s 267-foot working arm, or jib, into position, lowering a hook or coupling it into place, coordinating the connection, and then moving the object to the desired location.

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Scheduled to open in early 2017, the expansion will add more beds, private rooms, state-of-the-art operating suites, family-friendly amenities and the flexible floor space the hospital needs to adapt to new technologies and streamline services. The children’s hospital expansion is part of the Stanford University Medical Center Renewal Project, the largest construction project in Palo Alto’s history.

Man and machine

Barker is a second-generation crane operator, who learned the ropes by shadowing his father at work. By the time he was 10, he had soaked up the basics. Now, with 13 years of professional experience, Barker is so attuned to the nuances of his equipment that he can maneuver a joystick to pick up a five-gallon bucket, adjust its lid and place it on a table. A computer console displays the weight he is carrying, the trolley location, the degree of swing on the hook and the wind speed, though Barker said he only uses the computer for additional reference, focusing more on the crane and its load.

“It’s like driving a car,” he said. “Most of it is about feel. It’s a matter of making a connection to the movements of the machine. Though the models may be different, the basics remain the same. You have to adjust to how it handles, how quickly it responds. You learn to feel what to do and what not to do.”

Barker is familiar with the basic laws of physics, adjusting his speed and movements depending on the weight of his load and how far the trolley is positioned on the jib. The closer the load is positioned to the tower, the more weight the crane can lift safely. He needs to compensate his movements when there is a load of 8,000 pounds at the tip of the jib very differently from when there is a maximum load of 22 tons close to the tower. “The trick is to make only movements to control the load,” he said.

Barker stands on the counter-jib of the crane. 

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All channels open

He remains in constant communication with the men on the ground through two-way radios, while a direct phone line to the other crane operator prevents any overlaps of loads between the two massive jibs. Though the jibs are different heights and lengths —Barker’s is 267 feet long — the cranes’ loads could infringe on the other’s perimeter without perfect coordination.

“When the job starts you can see everything. But once the building goes up, you lose visibility, and there are a lot of blind spots,” said the 36-year-old father of three. “You have to rely on the guys on the ground to keep everything safe and up to speed. When you’re in the blind you depend on the riggers and signalmen.”

The signalmen give him explicit details so he knows how heavy a load to expect and where to move the trolley along the jib before he can lower his hooks. While placing gingerbread — smaller I-beams that reinforce the steel framework of the building — Barker responds to a series of nonstop radio instructions:

The site of the Lucile Packard Children’s Hospital Stanford expansion. 

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“Move it up a dog.”

“Left easy. Down easy.”

“Swing left. Up easy.”

“OK, we’re working. Down.”

'No room for error'

“You have to pay attention at all times,” he said. “There’s no room for error when you are flying iron and sending a load weighing thousands of pounds over to guys who are standing five stories high on beams that are 8 inches wide.” 

After climbing up to the cabin, Barker starts each shift with a safety inspection of the equipment on the counter-jib behind the cabin, eyeballing the hoist cable for signs of stress, lubricating the moving parts, and checking the tension on the tower section’s bolts and lattice. He’ll go over the plans with the signalmen for safety and efficiency, and discuss options for flying the loads. The crane operates in all weather, except in very high wind or lightning storms.

For Barker, working on the hospital expansion project is not a typical job site. While he can’t see patients through the existing hospital windows, he knows that his crane holds special fascination for little kids, and he makes it a point to wave or blast his horn whenever he sees families looking up at him from Welch Road.

Early next year, when all the structural steel is scheduled to be in place, Barker will move on to his next job, and the two tower cranes will be taken down section by section by smaller mobile cranes.

“I’m proud to be a part of a project that will make such a positive impact on so many children and families,” he said.

Stanford Medicine integrates research, medical education and health care at its three institutions - Stanford University School of Medicine, Stanford Health Care (formerly Stanford Hospital & Clinics), and Lucile Packard Children's Hospital Stanford. For more information, please visit the Office of Communication & Public Affairs site at

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