Posted for "Barney Briton" <bbriton@platinum.ca>:

 Dan
 
 In the professional flying realm of bus jets or airliners, 1.3 is used all
the time.  The difference is that it is calculated for each take off and
landing configuration as the speeds vary quite a bit for each weight senario.
 But, yes, 1.3 is the standard even on Boeings.
 
 Barney Britton