An F/A-18C Hornet from the “Wildcats of Strike Fighter Squadron (VFA) 131” hooks an arresting gear wire on the flight deck of Nimitz-class aircraft carrier USS Dwight D. Eisenhower (CVN 69).
LANDING AN AIRCRAFT ON A FLIGHT DECK IS ONE OF THE HARDEST THINGS A NAVY PILOT WILL EVER HAVE TO DO.
U.S. Navy photo by Mass Communication Specialist 3rd Class Ryan D. McLearnon/Released.
Assisted Take-Off But Arrested Recovery) essentially describes a system that both launches and receives an aircraft, with the catapult sending the plane forward, and hopefully aloft, and the arrestor wires catching it upon landing. STOBAR (Short Take-Off But Arrested Recovery) combines several methods of short takeoff and vertical landing, as well as catapult-assisted and arrested recovery. An aircraft carrier can launch a plane every 20 seconds from its four catapults. About 300 feet long, the catapults consist of a large piston beneath the deck—while only a small piece of the shuttle system engages the aircraft’s nose gear above deck. After all final checks are made, the pilot fires up the jet’s engines to full power. When the engines are steady at full, the catapult is fired, and the plane accelerates from 0–184 mph in less than two seconds. Te shuttle is then pulled back down the catapult by a cable and pulley assembly, and readied for the next launch. Taking off is ridiculously intense, but landing an aircraft on a flight deck is one of the hardest things a Navy pilot will ever have to do. Many more things can go wrong than right, with the primary objective being to hit one of four parallel cables— woven from high-tensile steel wire—with an extended hook attached to the plane’s tail. Te wires are connected at both ends to the arresting engines—large hydraulic devices below deck designed to spool out tensioned wire and absorb the aircraft’s momentum. An arresting wire system can stop up to 60,000 pounds of aircraft—with the breaking strength of the cable at around 250,000 pounds. Of the four wires, spaced fifty feet apart, a pilot is typically shooting for the third one—which provides the safest option. Te first wire is, more or less, an accidental snag—considered far too near the edge of the deck for comfort—while the second wire is acceptable, in theory. Te fourth wire obviously gets the job done, and is a last resort. But the third wire is what a good pilot aims to hit every time—the bull’s-eye. And as if this isn’t
22 SEPTEMBER-OCTOBER 2014 WIRE ROPE EXCHANGE
An F/A-18C Hornet assigned to the “Ragin’ Bulls” of Strike Fighter Squadron (VFA) 37 catches an arresting gear wire on the flight deck of the aircraft carrier USS Harry S. Truman (CVN 75).
U.S. Navy photo by Mass Communication Specialist 3rd Class Karl Anderson/Released.
WHEN THE ENGINES ARE STEADY AT FULL, THE CATAPULT IS FIRED, AND THE PLANE ACCELERATES FROM 0–184 MPH IN LESS THAN TWO SECONDS.
stressful enough, as soon as the pilot touches the deck, he or she actually has to push the engines to full power (the opposite of slowing down), because if the tailhook doesn’t catch, they need to be able to take off again using a terrifically short piece of runway—referred to as “bolting.” Obviously, arresting cables on deck (also called cross deck pendants) are incredibly strong ropes—that also maintain a surprising flexibility—each twisted around an oiled hemp core that provides cable lubrication and serves as a cushion for each strand. Cross deck pendants are replaced every 125 arrests, and common types vary from 1-inch (25mm) to 1 ¼-inch (32mm) to 1 ⅜-inch (35mm) diameter. Scholl personally designed a 1-7/16-inch rope in 1995 and WireCo® has been using it on awarded contracts since 1998. “We actually make two main types of arrestor cables for the U.S. Te 1-7/16-inch is a special Flattened Strand that is very strong, and has a smooth surface to catch the tailhook. Our ground-based 1-¼-inch rope has a different design, and is used for training and emergency landings around the world.”
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