There are at least 3 types of limits.
Calculated limits, Prooven limits and PFA limits.
The calculated limits, which include prooven and tested safety margins, lead to
testing, and if nothing breaks, flutters or otherwise falls apart, we have
prooven
limits. Then the PFA comes along and add their own safety factor on the
calculated and prooven limits. I have not been able to find any justification
for that PFA safety factor, other then the general fit-all: Amateur builders
make
mistakes. How on earth the PFA can stick a number to these mistakes i do not
understand.
All in all: Diving to PFA-Vne should be absolutely safe, it's some 20 knots
slower
then the calculated an prooven Vne. The Pfa knows it's safe, because they
did the bad builder calculation!
Is the same bad-builder safety margin enforced on glasairs and vans and the
like?
Are they to do that Vne dive, while their Vne is probably for real?
Regards,
Jos Okhuijsen
Visit - www.EuropaOwners.org
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