AFFDL-TR-70-107 0 CRACKS, A FORTRAN IV DIGITAL COMPUTER * PROGRAM FOR CRACK PROPAGATION ANALYSIS ROBERT M. ENGLE, IR. TECHNICAL REPORT AFFDL-TR-70-107 DDC OCTOBER 1970 f B This document has been approved for public release and sale; its distribution is unlimited. AIR FORCE FLIGHT DYNAMICS LABORATORY AIR FORCE SYSTEMS COMMAND WRIGHT-PATTERSON AIR FORCE BASE, OHIO Ruoproduced by NATIONAL TECHNICAL INFORMATION SERVICE Springfield, Va, 22151