Vne
Wow, thanks for all the replies. I've learned a lot from this discussion!!
Thats what makes this forum so valuable!! Here is what I have concluded - much
of this information is from
www.auf.asn.au/groundschool/umodule2.html#flight_envelope
Vne is defined by regulations as the indicated airspeed (IAS) which should never
be intentionally exceeded in a dive or other maneuver in smooth air.
However, unlike the performance airspeeds which are also specified as indicated
airspeeds, Vne is related to those structural characteristics and limitations
associated with bending, twisting and aeroelasticity which affect stability ,
control and structural integrity. Often Vne is related to flutter phenomenon
which tends to be excited by dynamic pressure which increases exponentially with
velocity, but Vne could be associated with other factors; for example bending
of the fuselage.
Indicated airspeed really reflects dynamic pressure rather than airflow velocity
so if the structural limitations which define Vne for an aircraft type are
particularly
associated with the distribution of forces associated with velocity
then the specified indicated Vne has to be decreased as altitude is increased
to adjust for the increase in true airspeed with altitude.
The article goes on to state that some aircraft (especially those being operated
at altitudes above 12500 ft) may have a Vne/altitude table which converts Vne
to IAS as a function of density altitude. I imagine that high aspect ratio
wings, like those on gliders, are susceptible to failure that is associated with
velocity and gliders certainly operate at high altitude when possible, hence
the caution in glider training manuals to convert Vne for density altitude.
I'm still curious as to what is Vne for the MG?
Jim Butcher
N241BW
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=82481#82481
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