How dangerous is flying in a single-engine plane?
I get this question a lot from people who are apprehensive about flying with a private pilot.  I'm afraid I won't be reducing these fears in any way.  Let's review some general statistics during 2008.  Note - these stats aren't specific to light or single engine aircraft:


NTSB reported there were 1.21 fatalities per 100,000 flight hours for private aircraft (Part 91 operators).  
NHTSA reported there were 1.26 fatalities per 100 million miles travelled by automobile


We can equate that to about 2 million hours (estimating an average speed of 50mph). This gives us 0.063 fatalities per 100,000 driving hours.

Private aircraft have a fatality rate about 19 times greater than driving.  It is also true that a majority of the accidents that occur are pilot error (71%) and could have been prevented. 

There are risks involved when taking to the sky as a private pilot and understanding these risks is part of the continual learning process.  The key to safety is performing careful planning, keeping current and proficient, knowing when to cancel flights or turn around and not to exceed your capabilities or the capabilities of your aircraft.