OSAN AIR BASE, South Korea - The bulk of the Air Force’s aircraft fleet
are several decades old, so preventive maintenance is very important to
the mission. A simple wash down and paint touchup can prolong the life
of a jet.
Aircraft structural maintenance Airmen from the 51st Maintenance
Squadron perform these maintenance procedures in the corrosion control
shop, also known as the “paint barn.” They identify, remove and treat
corrosion using mechanical and chemical procedures.
“Metals have a tendency to return to their natural state,” said Tech.
Sgt. Sameth Mao, 5st MXS NCO in charge of corrosion control. “Being
outside in the elements and even time can accelerate the corrosion
factor. It’s a man-made object so it will always corrode.”
Corrosion is a natural process that causes refined metals to convert to
more stable elements and compounds such as oxygen and hydroxide.
Prolonged exposure to air starts the process, so a sealed layer of
advanced protective coating paint is required for proper prevention.
According to studies performed by Bio Water Synergistics, a company that
specializes in aerospace wash equipment for the military, up to 80
percent of maintenance costs during an aircraft’s life span can be
attributed to corrosion, hence the importance of corrosion-control
procedures.
Aircraft are washed down every 90 days to remove the dirt, grime and
grease built up during flight that can hide any chips or gouges in the
paint.
“The advanced protective coating is expected to last for 10 years,” said
Staff Sgt. Alan Johnson, aircraft structures maintainer. “Per the AFI,
every 10 years the aircraft are repainted, but required touchups are
often done in the meantime.”
When aircraft go through phase, they are thoroughly inspected for
scrapes and gouges in the paint coating which might require touchups
after the maintenance is complete. If any are found, the aircraft is
delivered to the corrosion shop for the required painting.
“After we figure out which areas of the aircraft we need to paint, we’ll
start masking, putting down tape and paper, off all the areas that
cannot be painted,” said Johnson. “Once all areas are masked, we sand
the areas feathering and blending any chipped or nicked areas to provide
a smooth surface so the finished product looks even.
“After sanding is complete we wipe the areas to be painted to remove all
dust and debris, and once the areas are clean we spray a light coat of
primer,” continued Johnson. “When the primer has dried we spray the top
coat then let it dry.”
Mao explained that from start to finish, it takes about five work days
to completely sand, prime and paint an aircraft, then another 72 hours
for the paint to properly dry or “cure.” For the coating to dry properly
the hanger must being kept between 60-90 degrees Fahrenheit.
Once all preventive maintenance procedures are completed the aircraft is deemed serviceable and returned to active status.
Corrosion control’s aircraft structural maintainers extend the life of
each aircraft system that they work on keeping Osan’s aircraft
presentable and mission ready to fight tonight.