Interdisciplinary Program for Quantitative Flaw Definition Annual Reports
The following pages have been scanned from the original “yellow jacket” annual reports of the Interdisciplinary Program for Quantitative Flaw Definition sponsored by the Advanced Research Projects Agency (ARPA) and the Air Force Materials Laboratory (AFML), contract number F33615-74-5180, and performed by staff members of the Rockwell International Science Center teamed with subcontracting colleagues from academia, industry, and government. These reports cover the contractual period from June, 1974 to October, 1981. For reference, the numbers of the reports included in these scanned pages are: AFML-TR-74-238; AFML-TR-75-212; AFML-TR-77-44; AFML-TR-78-55;AFML-TR-78-205;AFWAL-TR-80-4078; AFWAL-TR-81-4080. In 1981 this program was continued at the Ames Laboratory (USDOE) and Center for Nondestructive Evaluation at Iowa State University by the same sponsors under a new contract until early 1994; however, the annual reports were discontinued as “yellow jacket” reports during this period, and instead, published in book form as the “Proceedings of the Review of Progress in Quantitative Nondestructive Evaluation”, first by Plenum Press and later by the American Institute of Physics, and edited by D.O. Thompson and D.E. Chimenti. The series continues to the present.
Seeds for this innovative program were sown with the introduction of fracture mechanics in the 1950–1960’s. This discipline introduced the concept of the “critical flaw” size into structural design; it specified that flaws below a critical size were not important to safety and that fulfillment of a “zero defects” criterion was excessive and acquired only at a high cost. Recognition of critically sized flaws led to the development of damage tolerant design. In contrast to the earlier safe life design and its “zero defects” inspection strategy, damage tolerant design permitted the existence of flaws in structures so long as they were below the critical size. Members of both the Air Force Materials Laboratory and ARPA became aware of major deficiencies in the then available inspection technologies to meet the new requirements of both quantitative detection and flaw sizing. Major research efforts were needed with a focus on focus on fundamentals in order to shore up major inspection technologies before reliable engineering tools could become available. In 1974 they initiated the contract for the Interdisciplinary Program for Quantitative Flaw Definition, of which the “yellow jacket” transcriptions described above are the first annual reports. The two objectives of this program were:
- Develop a new science base/people core that will meet the needs of damage tolerant design and set a new path for NDE.
- Set the stage for the development of new engineering inspection tools.
Donald O. Thompson
President, QNDE Programs
Founding Director, Center for Nondestructive Evaluation
Distinguished Professor (Emeritus) of Aerospace Engineering and Engineering Mechanics, Iowa State University
Member, National Academy of Engineers
Program Manager, Interdisciplinary Program for Quantitative Flaw Definition