After the Aging Aircraft Safety Rule went into effect in January 2008, the Federal Aviation Agency (FAA) quickly found that few in the aviation industry understood its requirements. At issue is effective performance of the analyses that lead to the damage tolerance-based inspections now required for all repairs and modifications to aircraft structures. To assist the industry with compliance, The FAA has partnered with University of Washington (UW) to provide an intensive week-long course in fatigue and damage tolerance analyses that will be repeated throughout 2009.
A government-university education partnership serving an industry need
Lead instructor Patrick Safarian, a damage tolerance technical specialist with the FAA Seattle Aircraft Certification Office (SACO), is also University of Washington affiliate faculty in the College of Engineering's department of Aeronautics and Astronautics. Safarian saw firsthand the need for such a training program.
"Out of a thousand [fatigue and damage tolerance analysis] reports I've seen before, maybe a handful of them were done correctly," he said. "So many professionals involved in determining the damage-tolerance based maintenance program for their organization are performing the analyses incorrectly. They simply miss the point of the regulations, and fail to properly show compliance. The result is inadequate evaluation of repairs and modifications to aircraft structures. This can lead to unnecessary delay in returning airplanes to service."
Continued Safarian: "Aircraft operators who want to modify their airplanes - say, install an antenna or repair it - what will they do [without training necessary to comply with regulations]?"
A deluge of inadequate analyses reports submitted to the FAA could result in a significant backlog. Anticipating the gap, Safarian sought FAA support to approach the University of Washington about developing a joint education program. The UW Fatigue and Damage Tolerance Analysis program is an intensive version of a course offered by the Department of Aeronautics and Astronautics, College of Engineering.
"The beauty of the class is that it's a joint industry-university-government agency partnership to address aviation safety issues," said course co-instructor Jason Dai, principal engineer at Structural Integrity Engineering, Inc., and an FAA Designated Engineering Representative. "It highlights the FAA's commitment to training and to support of the aviation industry."
Dai also notes the equal emphasis on theoretical fundamentals and practical application. "Participants bring their own problems to solve," he says. "We give them the tools they need."
Safarian's role as lead instructor ensures the emphasis on practical application. Not only did he serve as a technical advisor for the Aging Aircraft Safety Rule-writing team, but he will also educate FAA engineers on what to look for when reviewing compliance documentation submitted by applicants.
Approximately a dozen offerings of the intensive one-week course - the only such course in the nation co-sponsored by the FAA - will be scheduled over the next calendar year at University of Washington facilities in Bellevue, Washington. Additional locations may be scheduled in the future. Administered by University of Washington Educational Outreach, the course is approved by the UW's Department of Aeronautics and Astronautics, College of Engineering. Classes are capped at 30 participants in order to maximize interaction with instructors.
The first two offerings were held in November 2008, each drawing 30 participants nationwide from airline companies, leasing agencies, equipment manufacturers, after market modifiers of aircraft, maintenance facilities, and other commercial aircraft related organizations. Companies represented included The Boeing Company, Continental Airlines, Delta Airlines, US Airways, ABX Air, Inc. (a subsidiary of Airborne Freight Corporation), Goodrich, and Jamco America-Aircraft Maintenance & Engineering Co., Ltd., in addition to several independent FAA Designated Engineering Representatives.
Definition of damage-tolerance-based inspection
Damage-tolerance-based inspections and procedures are developed by a manufacturer or operator based on an engineering evaluation of likely sites where damage could occur, considering expected stress levels, material characteristics, and projected crack growth rates. They identify inspection sites, specify inspection techniques, define thresholds for the initial inspection, and prescribe repeat inspection intervals.
This is not a new concept: damage tolerance analysis has been practiced for thirty years. However, few professionals in the aviation industry possess this working knowledge unless they are a structural engineer employed by a large manufacturer such as Boeing or Airbus, says Safarian.
"This is an issue when all aircraft repairs and modifications made after January 11, 2008 must be ensured by the damage tolerance method," he said.
America's aging commercial fleet
The FAA Aging Aircraft Safety Rule was developed to support the recent operational rulemaking for all alteration and repairs on certain transport category airplanes to be damage tolerant. Aging aircraft has been identified as a factor in some accidents. The need to address this issue has increased with the trend toward keeping commercial airliners in service longer than was foreseen in the past. Safarian estimates that 2000 U.S. aircraft-approximately 25 percent of the commercial fleet-have been in operation for 20 years or more.
Said Safarian, "The University of Washington Fatigue and Damage Tolerance Analysis program supports industry and governmental efforts to maintain our commercial aircraft at the very highest standards of safety."
About University of Washington Educational Outreach (UWEO)
UWEO is the continuing and professional education division of the University of Washington, the nationally recognized public research institution based in Seattle. Helping the schools, colleges and departments to administer evening master's degrees, certificate programs, distance and online learning, international outreach, English language programs and more, UWEO is one of the largest and most highly regarded continuing and professional education programs in the U.S. (more information at the UWEO Web site.)
Emily West, Program Manager, UW Educational Outreach
firstname.lastname@example.org or (206) 221-3935
Patrick Safarian, P.E.
email@example.com or (425) 917-6446
Jason Dai, Ph.D.
firstname.lastname@example.org or (425) 493-2828 X20