Military News

Friday, June 19, 2015

Building barriers, aircraft arresting system protects planes, pilots

by Airman 1st Class Kyle Johnson
JBER Public Affairs

6/19/2015 - JOINT BASE ELMENDORF-RICHARDSON, Alaska -- The Air Force has a long history of breaking barriers. The Tuskegee Airmen broke the race barrier, Brig. Gen. retired Chuck Yeager broke the sound barrier, and then-Col. Robin Olds broke the mustache barrier.

However, there are some Airmen whose mission is to build barriers, not break them.

They build barriers designed to stop machines, which routinely blow through the sound barrier.

"A lot of people don't realize we have aircraft rescue systems on flightlines," said Chris Meyer, the foreman of power production with the 773d Civil Engineer Squadron. "We have five systems out there, and 365 days a year we are maintaining these systems to make sure they are fully operational and ready to go at all times."

These men and women are the power production specialists assigned to the barrier maintenance crew, 773d CES, and their job is to set up and maintain the BAK-12 aircraft arresting system.

"Electrical power production is broken into two different sections," said Staff Sgt. Jared O'Neill, a power production specialist assigned to the barrier. "The generator section deals with all the emergency standby power for the mission-critical locations here on JBER.

"The other side of the house is us, the barrier maintenance crew."

Every morning at 6 a.m., two crews of Airmen head out to the flightline to set up the BAK-12 systems that were not left up for night-time flight operations and perform their daily maintenance checks to ensure each system is fully operational, said Airman 1st Class John Arcarola, also a power production specialist with the 773rd CES.

"We check for leaks, the oil, the hydraulic system, the fuel, and the pumps inside the [shelters]; we also do weekly, monthly, quarterly, semi-annual and annual checks," Arcarola said.

The BAK-12 is not a barrier per se, but rather a steel cable strung across the flightline suspended two inches off the asphalt by a combination of tension and small rubber doughnuts wrapped around it. Those two inches of space are vital for allowing the incoming aircraft to reliably snag the cable, O'Neil said.

Attached to the cable is a nylon tape woven into a rubberized compound similar to the material of a golf ball, O'Neill said.

The tape extends from the cable for a few feet before dropping underground and connecting to 66-inch storage reel attached to a 65 horsepower, four-cylinder diesel engine in a small shelter on either side of the runway. The tape is held at a tension of approximately 170 pounds per square inch.

Once an aircraft takes the cable, the pressure on the tape is dramatically increased. This causes the hydraulic brakes to be incrementally applied to the turning reels of tape, providing the resistance needed to slow the aircraft to a gradual and safe stop.

"The reels spin at more than 600 revolutions per minute and hydraulic pressures can exceed 1,000 psi," said Meyer.

After the aircraft has been secured and the tailhook removed, barrier maintenance crew members have 10 minutes to reset the system so as to cause minimal interruptions to flightline operations, Arcarola said.

Because of this need for timeliness, two Airmen are on standby at all times, O'Neill said.

"We have a crash phone in here, much like a fire station would," he said. "in case there's an in-flight emergency."

When an aircraft comes to catch the cable, conditions may not be ideal, and sometimes the aircraft will not be able to strike the cable in the center.

"If the aircraft catches the cable on the left side, the right side is going to brake faster," O'Neill said. "It will allow the aircraft to be pulled back to the middle.

"We want him to come back into the middle and stay away from the edges as much as possible, to be as safe as possible."

This too, is checked quarterly.

When there are no checks to be performed, barrier crewmembers stay busy repairing generators, Arcarola said.

The power production specialists who are not assigned to barrier crew maintain about 85 generators around base, and the barrier crewmembers assist with that as well as all the mobile generators that can be deployed for anything from emergency operations to an installation picnic.

The barrier crew rotates with the regular power production crew every six months, O'Neill said. This ensures the Airmen are all able to fill whatever capacity they are asked in a deployed environment.

"With Northern Edge coming up, we will have 88 fighters out here, and these systems are going to be their final lifeline in the event of an emergency."

"Our [systems] have a huge impact on the Air Force mission," O'Neill said. "Without us, the Air Force could potentially lose billions of dollars in aircraft; and we [potentially] save the life of every pilot that uses one of our barriers."

No comments: