I fly at least once a month either transatlantic or to Europe and my 'survival bag' consists of the following:
Passport; for emergency use of boarding or exiting a plane
Wallet; to buy snacks or additional clothing if main bags are lost
Phone; to let loved ones and work know that I am going to be late due to delays
Kindle; to help pass the time when bored due to delays at the airport
All of which are stored convieniently in my pockets and will always pass through security.
In the event of a crash in open water what item of equipment would really help you apart from a PLB or boat? What would you really use a knife for when floating in the sea? Self harm or eating your fellow passangers?
In the event of a crash onto land that you survive all you need for short term suvival is onboard the plane - food, water and shelter. If the plane is on fire at least you will be warm for a few hours while you plan where to get water from....
