Never Ignore Symptoms: A Massive Failure of Rivets
Friend and airplane guru Jack remarked many years ago, "If you don't find anything wrong during your plane's annual inspection, you haven't looked carefully." We remember his comment every year when we inspect our plane, a Zenith 601HDS. This year was no exception to Jack's rule: We looked carefully and found two critical problems. First, the brake lining had to be replaced for the two main wheels. That wasn't unexpected since last year the wear marks of the lining were still okay but also indicated that replacement was in the near future. However, a major shock came as we cleaned the fuselage. The critical support bracket for the nose gear fastened with 13 rivets to the bottom of the fuselage near the firewall, wasn't attached at all: The entire set of 13 rivets had disappeared! The repair: We drilled nine of the 13 rivet holes to the next larger rivet size and installed the rivets, then enlarged the remaining four holes to 3/16 in. and used AN3 bo...