JOINT BASE SAN ANTONIO-RANDOLPH, Texas –
For years, members of the 12th Flying Training Wing
Maintenance Directorate corrosion control section washed the wing’s trainer
aircraft outdoors, where temperature extremes, inclement weather and water-use
restrictions often interfered with their work.
Those days are over.
The 14-member corrosion control team now has its own indoor
wash rack in Hangar 42 with benefits that include washes unimpeded by weather
conditions and an environmentally friendly water-recycling system that
conserves water, saving the Air Force $174,000 per year, said Lincoln Sundman,
12th FTW Maintenance Directorate aircraft maintenance supervisor.
The new wash rack represents the merger of two projects, he
said.
“We’ve got a good news-good news story here,” Sundman said.
“We have two different contractors … and we’re able to meld the two projects together
– one to turn the building into the wash rack and capture the water through the
ditch system that’s already in the building and the other to provide the water
recycling, which saves 1.4 million gallons of water per year.”
Not only does the water-recycling system conserve water, it
prevents contaminants from entering the San Antonio River Authority wastewater
system, he said.
Yet another benefit is the availability of soft and warm
water during washes and rinses, Sundman said. Soft water during the final rinse
helps prevent spotting, which can lead to corrosion.
Vernon Turnbull, 12th FTW Maintenance Directorate Fabrication Branch chief, sees three distinct advantages to the
indoor wash rack.
“First and foremost is getting the folks out of the elements
– San Antonio’s summer weather,” Turnbull said.
He said the optimum temperature range for washes is 40 to 90
degrees Fahrenheit.
Another plus is the wash rack’s new recycling capabilities,
Turnbull said.
“Recently we’ve been under water-usage restrictions and had
to defer washing aircraft for several months,” he said. “The new wash rack
allows us to keep the wash schedule mandated by Air Force Instructions.”
Turnbull said the wash rack also enhances efficiency.
“Going back to San Antonio’s weather, before we had to wash
each aircraft in sections as to not allow the soap to dry,” he said, noting
that soap drying on the aircraft causes corrosion. “This would effectively turn
a two-hour job into a four-hour job, so indirectly it increases productivity by
freeing up personnel sooner to focus on other maintenance tasks.”
The washing process begins with masking the aircraft for
water intrusion, followed by washing it with soap using scrub pads that won’t
scratch the paint, said Danny Rodriguez, 12th FTW Maintenance Directorate
corrosion control supervisor.
“We then rinse the aircraft with recycled water as we move
along, not letting the soap dry,” he said. “Once the aircraft is completely
washed and rinsed, we do a spot-free rinse. Then we de-mask the aircraft and do
a corrosion inspection.”
Water captured in the drain first goes to an oil-water
separator, where contaminants are captured and removed for disposal, and
travels through piping to the recycling system, which was installed by a
company that specializes in large-scale wash technologies and corrosion control
facilities designed for aircraft, military and other applications.
The recycling system is housed in a shipping container near
the front of the hangar and features a series of filters ensuring water in a
2,300-gallon water holding tank meets minimum filtration standards. The wash
rack also contains eight electric rewind hose reel stations.
“Water from the drain goes into the filtration tanks,”
Rodriguez said. “The tanks are stainless steel settling and oil-separation
modules. Water is filtered, then run through a reverse-osmosis system before
being introduced back into the wash cycle.”
The corrosion control section washes aircraft at a rate of
two per day, four days a week, Sundman said. Most of the wing’s aircraft have a
90-day wash cycle.
Sundman said aircraft are subjected to temperature extremes
and condensation, which causes metals to corrode, so washing aircraft on a
regular basis is important to combat corrosion.
“The last thing you want for high-performance aircraft is
for the structure to get weakened by corrosion,” he said.
Sundman said converting Hangar 42 into a wash rack was
challenging, but the conclusion of that 15-month project merged seamlessly with
the installation of the recycling system, which was completed in one month.
“You don’t see what this building used to look like,” he
said. “It used to have insulation sprayed everywhere inside that had to be
removed. So we had about three or four months when people were in here in
spacesuits trying to take all that insulation off everywhere – from the roof,
the walls and all over.
“By the time the building was released to us,” Sundman said,
“the water recycling system was also done, so we were able to start our very
first washes with recycled water and not ever waste any water or put any
contaminants into the sewage from this operation.”
Although the hangar, which had most recently been used for
storage, was challenging to retrofit from an environmental standpoint, it
already had a drain ditch to capture water from the washing and rinsing process
for recycling.
Sundman concurred with Turnbull that being indoors is one of
the big advantages of the new wash rack.
“This allows us to
wash aircraft year-round,” he said. “We don’t have to worry about it being too
cold, too wet, too hot or too sunny. We also don’t have to worry as much about
corrosion on the aircraft.”
Mario Tarin, 12th FTW Maintenance Directorate corrosion
control work leader, gave the hangar and recycling system high marks.
“We really like it,” he said. “It takes us out of the
elements and makes our job easier.”