I believe that planning succeeds better than just ESP. If you need parts, you always need to have at least two suppliers for each part and hopefully three or more. Why? Just for the reasons you stated. In a crunch, you need options. If you have a sorted list of suppliers, you can quickly find a replacement source for a while if your primary source experiences unexpected difficulties.
It is all about good risk management and planning.
Just my opinion.
Drones are, in essence, flying autonomous vehicles. Pros and cons surrounding drones today might well foreshadow the debate over the development of self-driving cars. In the context of a strongly regulated aviation industry, "self-flying" drones pose a fresh challenge. How safe is it to fly drones in different environments? Should drones be required for visual line of sight – as are piloted airplanes? Join EE Times' Junko Yoshida as she moderates a panel of drone experts.