"Gary Drescher" wrote in message
snip
Yes, students should definitely be taught which V-speeds need to be
weight-adjusted and which do not (and why). If you're 30% below gross
weight, the required 15% speed adjustment is nonnegligible. (Adjust Vs,
Vs1,
Vl/d, Vx, Vy, Va. Do not adjust Vne, Vno, Vfe, Vle. See
http://www.av8n.com/how/htm/aoa.html#sec-ias-aoa for a detailed
explanation.)

But no, you don't do the calculation when an emergency arises. You should
do
it in advance, as part of your W&B calculation. If you precompute the
adjustment factor, you can easily apply it in real time.

Gary , I dont disagree with you . I do actually have a best glide speed wt
adjustment in my Excel wt and balance spreadhseet but as a student we were
not taught to adjust these speeds for weight, although we understood they
change with wt. and we certainly knew the non -negotiable ones like Vne and
Vfe etc. Again I figure their reason was to keep things simple, better
to overstimate than underestimate stall speeds. . although in hindsight it
had a lot to do with my early landing problems in the Warrior where it just
seemed to want to float for ever. I did actually post about this on this
group some years ago, because I thought the approach speeds I was being
taught were too high relative to the stall speed for the wt I was carrying
The 12 hour formal theoretical training I recieved for PPL was typical of
what seems to be happening with science education in our schools and
Australian society in general at the moment... a dumbing down to take maths
out of everything. But being a scientist myself I believe in the Lord
Kelvin theory. " if you cant explain what you know with numbers, your
knowledge is of a meagre and unsatisfactory kind" .. or something like that.
I have probably gone the other way now having set up spreadsheets to do my
Navigational wind triangle calculations ,great circle distance calculations,
calculating wt adusted stall speeds , wt and balance, turn physics ( radius
and time) , load and stall speed increase in turns , and my latest additon
is my energy balance to answer the question of how much ht I can actually
gain by turning speed to height. ( not much in a Warrior - 250 ft from
cruise to best glide speed after engine failure . but I havent allowed for
drag so it will be a bit less.). You know that Count character in Sesame
Street.. he's my hero.
terry