2leftskids
Here's a bit of offshore twins vs singles reading
http://www.ogp.org.uk/pubs/300.pdf
It's only a snap shot for 1 year but it is worldwide
Of the 47 fatalities worldwide the figures were :
57% in medium twins
21% in light twins
17% in singles (none due to engine failure ??)
4% heavy twins.
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99%
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In a year when 49% (23) of fatalities were caused by mid airs, this data doesn't really, IMHO, apply here.
Interesting to read Appendix C
If you like to throw figures around, notice the singles accident rates compared to all the twins put together!!!