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Old 4th Apr 2014, 02:27
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john_tullamarine
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Most manufacturers POH for light aircraft refer to lift-off speed and 50 foot barrier speed

Probably because most manufacturers endeavour not to go too far beyond what the design standards require ... Also it is reasonable to presume that OEM paperwork is structured with a very close eye on liability ..

I'm pretty sure that take-off safety speed is a uniquely Australian manifestation

Probably not quite the case. 1.2Vs for singles has long been held as a reasonable balance between too slow and too fast in the event of a failure. The US regs reflect this. I expect djpil will endorse my view ...

Probably reasonable to opine that Oz has, for many years, used the Vtoss abbreviation as a convenient shorthand.

this is not 1.2 x the stall

Be careful of PEC. The 1.2 is not applied to IAS. As PECs can get more interesting in the near stall regime, this is a common error amongst the pilot fraternity. Indeed, we proably have all flown Mr Cessna's fine products and enjoyed the observation of "zero" IAS with the nose pulled way up above the horizon .. doesn't mean anything useful though ... and most certainly doesn't indicate that the aircraft is traveling along with no airspeed.
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