Two things I've noted about this issue.  First, the early brochure for the ES listed dirty stall as 58 mph.  That's right, MPH (factory guys, please don't take this the wrong way).  That's about 50 knots.  Would someone please tell me the conditions required to produce a stall in the ES of 50 knots?  How about the 210 HP engine, one person on board, and an hour of fuel.  Maybe that would do it.

I raise this because the "book" stall in the brochures has always been a little optimistic.  The current number, 65 mph, is about 57 kts.  From what I've seen on the lists, people get more like 60-62 kts (about 70 mph) in their testing. Note that 1.3 times 62 (not 1.3 times 57) is about 80 kts, which is the minimum approach speed recommended in the ES manual that Carsten put together a few years ago.  (That manual says do 80-85). 

Second, I wonder if it possible that the rule of thumb of 1.3 times the dirty stall is more applicable to relatively idiot-proof wings like those found on C172 & 182s than it is for Lancairs?  I'm no aerodynamicist, but I know from reading about wings that the stall of the wing on the ES and IV is sharper than the stall on the Cessna.  It always seemed to me that the difference in the wings could justify a greater safety margin.  (It seems there is no free lunch, except on the Columbia which, like Roger Federer, is practially spin proof AND has a slick wing).

Anyone know if business jets, which also have slick wings, use more than 1.3 times the dirty stall?  Just curious.