Maintenance: Hangar Stacking Wizards Share Their Best Practices

Stacking a hangar – safely arranging as many aircraft as possible in a hangar without damage – takes patience, teamwork and skill. This work falls to line technicians, who can spend hours moving aircraft of different dimensions in and out of crowded hangars.

“In planning optimal parking, stack with unstacking in mind,” said Gene Velazquez, president and founder of One Mile Up Inc. “Somebody has to get that aircraft out of that hangar, probably the night shift, maybe with different towing gear.”

“When trying to maneuver in and out of a hangar, you need a team,” said Michael Beasley, who spent several years at Galvin Flying and Landmark Aviation at Seattle’s King County International Airport – Boeing Field (BFI). “You must think three-dimensionally and your walkers are more eyes for you. Go slowly and give them time to react and warn you if you’re getting too close to something.”

“The wing walkers need to know they’re not just holding a wand with a whistle in their mouth. They’re irreplaceable to safely filling a hangar,” Velazquez added.

Take Care With Swept-Wing Aircraft

Experienced Line Service Technician Adam Castle, currently at Skyservice, shared tips on towing swept-wing aircraft. “These planes have wings that are at a strong backwards angle from the nose,” Castle said. “When they’re turned, the wing on the outside of the turn will seem to ‘grow.’ You need to be very careful about the clearance you leave on the outside wing as it will sweep outwards much faster than you would expect.

“The pivot point of the plane plays a large role in how to approach the parking spot,” he continued. “If the plane has a long wheelbase, from mains to nosewheel, then at the right angle you can get the inside wingtip to stand still as the rest of the plane seems to pivot around it.”

It is also important to disengage rudder locks before an aircraft is towed, Castle said, and be careful about the angle of a turn when pushing the aircraft back as it is possible to jackknife the towbar.

“Always keep one eye on the tail of the aircraft as that will give you a much more visible cue as to which direction the plane is turning,” said Castle. “When pushing the plane, the sharper the angle gets, the faster it will continue to turn. Looking at the tail will allow you to anticipate this rapid turn quicker and adjust for it.”

Game Out Your Hangar Stack

Line Service Technician Kristina Fudge, with Modern Aviation, advises techs to take time in advance to create a specific plan that includes the least amount of tow movement possible.

“Pull large aircraft and push small aircraft into the hangar,” Fudge said. “The way most hangars are designed, it’s typically the best fit to have the noses of the larger aircraft in the corners and have smaller aircraft tails tucked in behind. This allows for the best use of the space. Every tow movement has risk, so having the best placement strategy is a must.”

Putting airplanes straight back into the hangars doesn’t usually work, said Fudge. “Angling, working from the corners inwards, typically allows for the best fit.”

“Following a parking plan takes prudence,” Velazquez added. “That means wisdom in action.”

Review NBAA hangar safety resources at nbaa.org/hangar-safety.