On 1/14/21 2:11 PM, Eric Greenwell wrote:
Moshe Braner wrote on 1/14/2021 11:39 AM:
On 1/14/2021 1:43 PM, John Galloway wrote:
...

Another huge advantage, is they don't have that all-flying tail, which
was quickly designed out of the Nimbus line, for good reason.

The late models DG100G, LS1F and Grob built Std Cirruses have
conventional tailplanes. Earlier variants of those 3, and the ASW 15
have all flying tailplanes.


OK, but what is so bad about the all-flying tail?Â* I know some models
had a reputation for no "feel" in the pitch control.Â* Others less so.
Is it the all-flying tail, or some details of its design?Â* Where the
hinge is placed along the chord of that tail would make a big
difference, no?Â* And spring trim added to the system would make it
behave better when hands-off?

For example, Dick Johnson was regularly flying a Nimbus 2 IIRC, when
he did the flight test of the original Janus (both with all-flying
tails). Â*He commented that "The well-balanced, all-movable horizontal
tail (on the Janus) provided good longitudinal stability at all speeds
and was a great improvement over the smaller poorly balanced Nimbus
and Std. Cirrus tails. It did, however, cause the longitudinal control
to be fairly sensitive to control stick position."

My Ka6e and Std Cirrus both had all-flying tails. Based on those gliders
and comments from other pilots in different gliders, I'd say "did cause
the longitudinal control to be fairly sensitive to control stick
position" is what's wrong with all-flying tails, especially at high
speeds. Over 75 knots, I held the Std Cirrus stick in both hands, ditto
for the Ka6e at some slower speed I don't remember. I very much liked
both those gliders, but it was a deep pleasure to leave those gliders
for the H301 - so steady at high speeds.


Having logged 1200 hrs in a Ka6Cr, I must say it never occurred to me to
ever use both hands on the stick at higher speed. Such a sweet flying
glider. Maybe because it had the conventional tail, unlike the E model?

We've really beat this topic to death, but just to summarize, we have a
low-time pilot who think he's discovered some secret loophole that lets
him buy a great open-class ship for dirt cheap, and fly it on 500K tasks
in armchair comfort, with apparently no risk of landing out due to long
wings. He thinks he'll grow into it. To fly 500K you need some speed,
and developing that in an old boat like this would be really tough for a
beginning x/c pilot.

Dick Johnson said the tail is small and poorly balanced, yet some people
still claim this is a suitable glider for a low-time pilot. I know this
is R.A.S., but even so, it's time for some common sense to kick in.
Glider are expensive toys, that's unfortunate. But ignoring reality
doesn't change facts. There's a real good reason the open class ship
he's looking at is offered so cheap.

-Dave