With the economy struggling worldwide, aging aircraft have become a serious issue. Thanks to some harsh lessons (Aloha 243, TWA 800, United 232, ASA 529, etc.), the world has already learned that the effects of corrosion and fatigue can be deadly and need to be dealt with accordingly.
Organizations like the Joint Council on Aging Aircraft (JCAA) combining U.S. DOD and FAA efforts, and CASA (Australia) are doing their best to remedy the situation. So far, the methods of dealing with aging have focused on increased inspections, repairs, and maintenance, with massive costs and a great deal of Aircraft on Ground (AOG), or retiring the aircraft and simply buying another. With people struggling to keep money in their pockets and the current economic climate, it’s becoming less and less likely that anyone will be able to afford either option.
Because of this, aircraft all over the globe are being kept in the air longer and not always maintained as directed by their country’s or even the manufacturer’s requirements. Not only are they endangering themselves, but the rest of the world’s population as well. Fourteen percent of all aviation accidents are due to maintenance problems involving a lack of detection of either fatigue or corrosion damage. Even the U.S. Air Force, with a 23-year average age for the fleet, has issues with detecting these faults. The tiniest crack or weak spot in any aircraft component could be catastrophic and the burden of detection is solely on the shoulders of appointed inspectors and maintenance personnel.
Due to these facts, in the United States the FAA requires every plane to undergo a 14-day, 100-hour maintenance check on the craft’s 14th anniversary of service and every seven years thereafter. Brandon Battles, vice president of the aviation and consulting firm Conklin and de Decker, says, “Regardless of the class or type of aircraft … maintenance costs can range from 10 to 45 percent of the total yearly estimated operating expenses. Ten percent might not seem significant but when total operating costs can be in the hundreds of thousands or millions of dollars, then even 10 percent becomes significant.”
One company involved in the making of the FAA’s Aviation Safety rule estimated that this would cost his business an additional $363 million per year in rescheduling and $285,790,000 in lost revenue. In 2006, the International Air Transport Association (IATA) reported that anywhere between $300 and $1,800 is spent on maintenance per flight hour, the exact average being $870. Of course, the price will vary with a number of factors, one of these being the age of the aircraft. Unfortunately, even all of these costly regulations and precautions won’t necessarily save us from our aging aircraft.
As a result of their complex construction and the fact that they’re under the most stress, engines (particularly turbine), propellers, and retractable landing gear are the most likely components to experience failures due to fatigue or corrosion. Foreign object damage (FOD), such as a small rock striking the propeller, could create a weak spot and the fatigue originating from that impact could eventually force the component to fail. Engines are accountable for 40 percent of all maintenance costs. On more than one occasion, blades have flown off their engines. Manufacturers even place a protective capsule around the blades now to prevent them from shooting into the fuselage should a failure occur. And though it will increase your velocity by 12 to 20 knots, retractable landing gear alone will add four to six hours of maintenance to annual inspection times.
Regrettably, some replacement components required for repair are no longer being manufactured or have excessive lead times, resulting in increased AOG or even early retirement.
LPB uses residual compression by design to increase damage tolerance in metallic components, greatly extending their service life
Pacific Propeller International has begun robotically processing aircraft components for the US Navy, using Lambda Technologies' patented low plasticity burnishing (LPB).