With any new thing, there is usually a bathtub curve of corrective maintenenance. The initial design is also much the same way.
It happened with some frightening engine problems in the A380 Super Jumbo jet. Such discoveries are to be expected. If flying scares you, then adjust your expectations accordingly. Just remember that even a very well designed, time tested aircraft can still be destroyed by a brief moment of inattention by the pilot, as evidenced by the unfortunate 777 crash at San Francisco airport recently.
Producing high-quality end-production metal parts with additive manufacturing for applications like aerospace and medical requires very tightly controlled processes and materials. New standards and guidelines for machines and processes, materials, and printed parts are underway from bodies such as ASTM International.
Engineers at the University of San Diego’s Jacobs School of Engineering have designed biobatteries on commercial tattoo paper, with an anode and cathode screen-printed on and modified to harvest energy from lactate in a person’s sweat.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.