When a sequence of positive events occur we use the term miraculously. What about the opposite, when a sequence of bad luck events occur, how can we characterize it?
Here is the story of a flight which, despite many odd errors, had a miraculous landing (or a very skilled crew). How can we refer to the string of breakdown of all checks and balances in the pre-flight stage? (Somebody under-fueled the jetliner, various equipment did not work properly and the jet took off with much less fuel than needed for the flight.)
What I learned are, depending the context and connotation,
for comic effect the recommendation is Murphy's Law or Sod's law
for secular effect use perfect storm, * a cascade of failures*
for other-worldly effect use fatefully