All for the Want of a Horseshoe Nail

I just finished watching one of my favourite programs on television. It is called Mayday and is for me the fascination of horror. It is the reenaction of air, sea and rail disasters and the subsequent research as to how it happened and how it could be prevented from happening again. Riveting!
This episode was about a B.A. flight from Birmingham to Spain. They were but a few minutes into the flight when the window blew out taking the pilot with it. He was held by the legs by cabin crew while the poor co-pilot { it was his first time on that aircraft} got the plane down in one piece. Facinating as that was, the real interest began when the hunt was on for why it happened. I won't say anymore as you may be watching the Discovery Channel one day and find yourself watching this and I don't want to spoil the surprise ending for you.
I will give you a clue. There is an old nursery rhyme about the downfall of Richard the Third of England in the Battle of Boswell.
" For the want of a nail the shoe was lost; for the want of a shoe the horse was lost; for the want of a horse the King was lost; for the want of the King the battle was lost; all for the want of a horseshoe nail!"
Not to belabour the point but almost always, unless someone was asleep at the switch { which has happened! } these accidents are tiny mistakes people make unwittingly that balloon into catastrophes. You know what they say: live in the now.