Military News

Saturday, December 19, 2015

Airmen create works of art with metals technology

by Airman 1st Class Kyle Johnson
JBER Public Affairs


12/14/2015 - JOINT BASE ELMENDORF-RICHARDSON, Alaska -- Off Japan's east coast, The Continental Plate and the Pacific Ocean Plate meet to form the Japan Trench.

On March 11, 2011, the downward pressure from the Continental Plate on the Pacific plate suddenly released, causing it to surge more than 200 feet upward, triggering a magnitude 8.9 earthquake - named the fourth-largest earthquake in modern history.

The temblor and its subsequent tsunami killed more than 15,000 people and displaced more than 200,000 more. Amid the devastation, it also started the a ticking of a time-bomb 130 miles north of Yokota Air Base, Japan.

A nuclear power plant began to melt down.

"If they don't have cool water consistently pumping through the plant, it overheats. When the tsunami came, it wiped out their backup generators," said U.S. Air Force Staff Sgt. Jeremy Hamblin, 3rd Maintenance Squadron aircraft metals technology craftsman. "At that point they were unable to keep the plant cool, and with widespread power outages, they didn't have a good way to tell people what was going on, either."

In less than a week, the Royal Australian Air Force showed up with new water pumps, courtesy of the U.S. government, for immediate use in cooling down the reactor. However, the Japanese hoses did not fit the new water pumps, and they could not be used. The reactor continued to heat up.

Hamblin, then an Airman first class at his first duty station, was one of eight metals technology Airmen who immediately began 12-hour shifts.

Their task was not simple: draw, design, and create adapters so the Japanese hoses could securely connect to the U.S. water pumps - and do it quickly enough for them to be implemented before a nuclear meltdown.

Two days later, the parts were delivered, and a catastrophe was averted.

While this is by no means an average day for metals technology Airmen, it is what they're trained to do.

"We're here to support the aircraft and all the support equipment for the aircraft. We do everything from welding, to machining, to sometimes prototyping and manufacturing," Hamblin said. "The majority of our work is split between aircraft and support equipment."

Often, their work takes them out on the flightline to measure damage to aircraft. Even the most minute of damages, like a shallow scratch may render a piece of equipment non-mission-capable.

Aircraft metals technology Airmen are like the happy union between graphic designers and blacksmiths wrapped into one Air Force package, but before they draw, or put a piece of metal in their 2,900-degree furnace, they measure.

"The tools we use are hand tools like micrometers, dial calipers, and pick calipers - which have a point on them so fine you can measure the depth of a scratch. Some of the calipers we have can measure a 30th of a hair's thickness," Hamblin said. "So if you took a human hair, cut that into three pieces and cut each of those into 10 pieces, we can measure the thickness of that. It's really precise. We go out there and give them an exact measurement on the size of the damage so the engineers can go back, evaluate it, and decide if that's something that is repairable or if it's something that's going to have to be replaced.

Some parts may allow zero damage, but some parts may allow what we would consider quite a bit of damage," Hamblin said. "The standard is different for every part."

Often, if it is determined that a part is in need of replacement, and the part cannot be ordered in a timely manner, people turn to metals technology for help. This creates some unique opportunities: like creating adapters for coolant hoses to avert a nuclear meltdown.

More recently, Hamblin had a similar opportunity; he's now machining the first-ever Air Force manufactured F-22 Raptor Infrared Countermeasures bucket bracket.

"The IRCM bucket bracket holds the dispensers that go on the side of the aircraft. Whenever there's a threat, it can dispense countermeasures through those brackets," said Steven Mate, 3rd Maintenance Squadron, Aircraft Metals Technology foreman. "The original bracket in the airplane was damaged and it had to be replaced. Currently, the aircraft is only partly mission-capable with the damaged bracket in it, meaning they can't put any of the electronic countermeasures in on that side."

The IRCM, like many F-22, parts has been designed to be as thin as possible to save weight, Mate said. Because of this, there's not much room for damage before a part needs to be replaced entirely.

"Being an F-22 part, it wouldn't typically be made in an Air Force shop. It would be handled by the factory," Hamblin said. "We aren't typically allowed to make aircraft parts of this caliber, specifically on this aircraft."

"Lockheed was going to make the new part, but the soonest they could get it to us was the latter part of February 2016," Mate said. "So we started doing some research to see if we were going to be able to make it. After evaluating the drawings, we stated we could make it."

So Hamblin and his co-workers set to work measuring the model Lockheed Martin sent in with their portable coordinate measuring machine - which looks roughly like a high-tech hot-glue gun attached to a jointed carbon fiber arm and a red circle at the tip of the nozzle.

"Basically you're measuring coordinates in a 3-D space," Hamblin said as a 3-D printer hummed away on a different project behind him. "That machine can tell you exactly where every point on a specific thing is in that 3-D space."

The arm uses software and materials so complex, it costs upwards of $120,000, Hamblin said.

"We reverse-engineered it by measuring it with the Romer arm and feeding the measurements back into the computer with the blueprints," Mate said.

Once they had the measurements, the metals technology Airmen assumed the role of graphic designer and drew the part in their custom-built computer from scratch, using $15,000 3-D modeling software.

"The drawing part is the easy part. That's the part everyone picks up on," Hamblin said. "It's the same as using paint. When you're telling it how to cut that box, that's when it gets really complicated."

They draw the part by using a series of lines separated and organized in such a way that it looks like a 3-D blueprint. The program sees the lines as toolpaths, which are best described as digital "roads" it creates for the computer numerically controlled machine to follow with its tool bit.

"It converts the inputs into what's called G-Code," Hamblin said. "Then reads that to give the machine coordinates on where to move, how to move, what speed to move and we can cut pretty much any shape we want out of a piece of metal."

The program may be giving the machine those details, but someone has to tell the program what to translate, Hamblin does that, right down to the thousandths of an inch.

"This program is where the real parameters are. You're telling it how much material to cut per rotation, so say I only want to cut .001 inches per rotation, so every tooth on that cutter is going to cut one thousandth's thickness, I'm telling it how fast to spin the spindle, because that changes with the material, I'm telling it how fast to go in, how fast to come out, how fast to move across the machine, and what angle to do each of those at."

The Airman has to know the kind of metal they are working with too, and not just whether it's aluminum or steel, but what grade of aluminum or steel, because different qualities can take different levels of heat, which affects how fast the machine can carve the part out of the block of metal it's working with. That includes when to wash the block with coolant and how often, Hamblin said.

"This [program] is another tool, that's all it is."

Each of those details can affect another detail, so they compound together and create a complex web of commands the Airman is directly giving the machine.

Once those commands are laid out, they can run a simulation of the project and determine if the part meets their precise requirements. This is vital because a mistake by even one thousandth of an inch could cost the Air Force thousands of dollars in special alloys the jets need, Hamblin said.

At the end of the day, a metals technology Airman uses 3-D modeling programs like a graphics designer to sculpt precise parts out of a block of material much like an artist would out of marble. That's when they're not heat-treating metals like a blacksmith with a furnace so they can harden or soften them.

"What I love the most about my job is when somebody comes to us, we're the last thing there is. If we can't fix it, it's done, it's broke," Hamblin said. "You're going to have to get a new one."

Last resort indeed - when the Earth itself shakes, a few Airmen from the Aircraft Metals Technology Flight can help.

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