Which is the safest aircraft in terms of fatalities per person hours flown:
- Dehavilland Dash 8 Turboprop
- Boeing 777

Hi there blue_moon!

The Boeing 777 is by far the safer aircraft, because it has never had
any crashes in which there were fatalities.

You can verify this at the excellent aviation safety site,
AirSafe.Com, which is a great resource for this kind of information.

AirSafe 777 Information: http://www.airsafe.com/events/models/b777.htm

The Dash 8 has had at least one fatal incident. The one which gained
my attention was the tragic story of a crash in New Zealand in which
four lives were lost:

A small report is here:
http://www.ntsb.gov/ITSA/new_zealand_investigates_dash_8_.htm

One more site which may interest you is the National Transportation
Safety Board, which runs a searchable database of all incidents, fatal
or not. You can find it here:

http://www.ntsb.gov/ntsb/query.asp

I hope this answers your question. If anything is unclear, or you
would like me to explain something more fully, then please don't
hesitate to request clarification before rating this answer.

--seizer-ga

Search strategy: Prior knowledge of AirSafe.com, and searching for
"Dash 8" crash.

I'm not directly criticising the answer but the question as posed
needs a little examining. If the 'safest aircraft' is the one that has
had fewest crashes then the 'safest aircraft' is the one kept locked
in a hanger !

Factors such as distance flown by type and number of ratio of
takeoffs/landings to distance flown (takeoffs/landings being the
dangerous bits) need to be thought of just for starters.

Other factors that spring to mind are the operators of the aircraft. A
smaller aircraft is typically flown by smaller operators which _may_,
on average, have lower maintenenance quality then larger operators.

My feeling (and it is only that) is that the nature of the operator
(pilot training, aircraft maintenance and nature of airports serviced)
would outweigh any variance intrinsic to most commercial aircraft.