Cirrus vs ASW

I have not flown a Schempp Hirth design with an all
flying tail (stabilator), but I've flown my LS1-d,
which does have an all flying tail, for over 10 years,
and you can trim it and let go of the stick. No problem.
If I need both hands to open a snack or change my
sunglasses to my clear glasses, I can easily set up
the ship to fly itself. You don't have to 'mind the
store' every second.

I haven't tried this above 60 knots, but below 60 knots,
there is no problem. And because it trims nicely at
75 knots, I'm sure it wouldn't be a problem to let
go of the stick for a few seconds at that speed either.
Usually, I only need to let go for a couple of seconds.
It doesn't take long to peel a banana or open a pack
of 'nabs.'

Ray Lovinggood
Happy Owner of LS1-d
s/n 27, 'W8'


At 00:00 21 March 2006, Robert Hart wrote:
Jeff Runciman wrote:
Thank you for all of your help.

It turns out the ASW is 50,000. The Cirrus makes
me
a bit nervous with the tail (attaching and flying)

I've not had much to do with Cirrus's - but I have
had to deal with the
same all flying tail plane on a borrowed Nimbus 2 whilst
my 2c was in
for repairs (see
http://www.hart.wattle.id.au/alice/a...ice3mar04.html).

I too was somewhat twitched at the stories I had heard
about the all
flying tail and its sensitivity, so my first launch
had me waiting in
some apprehension - which was completely unwarranted.

Whilst the all flying tail does mean that you shouldn't
let go off the
stick at high speed (or even for long at low speed)
it does not make the
aircraft unstable in pitch. It's certainly more sensitive
in pitch and
PIOs are easier to do - but remember a PIO is a PILOT
induced
oscillation and not a problem with the aircraft!

As for rigging and making sure the elevator is correctly
attached, it is
a bit difficult at first, but after a couple of goes
it didn't present a
great problem.

I did however do an extremely careful loaded control
check as part of
the DI (get someone to hold the all flying tail to
restrict its movement
and then firmly move the control column) to ensure
that it truly was
attached and not just 'resting'!

I would suggest you don't rule out a Cirrus just because
of the
'stories' about the all flying tail. It is my experience
that these are
exaggerated - but do of course contain a kernel of
truth as noted above!

Robert

Ray Lovinggood wrote:

I haven't tried this above 60 knots, but below 60 knots,
there is no problem. And because it trims nicely at
75 knots, I'm sure it wouldn't be a problem to let
go of the stick for a few seconds at that speed either.
Usually, I only need to let go for a couple of seconds.
It doesn't take long to peel a banana or open a pack
of 'nabs.'

It isn't a trim issue on the Std Cirrus, it is a G induced control
movement. It does not have a "balanced" elevator drive mechanism,
meaning a positive G surge tends to _increase_ the amount of "up"
elevator, which tended to increase the G loading, which ... you get the
idea. You can feel the stick reacting to bumps and surges as you fly it
a higher speeds. That was why letting go of the stick a speeds over 80
mph in my Std Cirrus was most unwise. At lower speeds, especially
thermalling, no problem.

--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"

Eric Greenwell wrote:
Ray Lovinggood wrote:

I haven't tried this above 60 knots, but below 60 knots,
there is no problem. And because it trims nicely at
75 knots, I'm sure it wouldn't be a problem to let
go of the stick for a few seconds at that speed either.
Usually, I only need to let go for a couple of seconds.
It doesn't take long to peel a banana or open a pack
of 'nabs.'


It isn't a trim issue on the Std Cirrus, it is a G induced control
movement. It does not have a "balanced" elevator drive mechanism,
meaning a positive G surge tends to _increase_ the amount of "up"
elevator, which tended to increase the G loading, which ... you get the
idea. You can feel the stick reacting to bumps and surges as you fly it
a higher speeds. That was why letting go of the stick a speeds over 80
mph in my Std Cirrus was most unwise. At lower speeds, especially
thermalling, no problem.

You can release the stick for short periods in a Std Cirrus. It is not a
fearsome beastie that will bite the moment it is not being actively controlled.
There is no stick free stability, so if you let go for any length of time the
airspeed will slowly diverge into a phugoid. On mine the amplitude also slowly
increases. Turbulence can trigger sharper divergences, but you would surely not
be flying hands off in this situation...

Often the best way to improve thermal centering is to stop flying - in my case
the Cirrus is generally better at grooving a thermal than me, the lighter touch
really works a lot better. If you like to make big positive control movements
before antything happens get a Grob 103...

At high speed it is a different matter. Again I find the pro-disturbance
movement helps. You get an automatic "mini pull up" in any good surge of lift.
If you want to take it you follow through, if not you correct.

The Jantar is apparently also nice and light on the controls. WOuld not go wrong
with one of those either.
--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.

At various times I have owned a Cirrus 75 and a Nimbus
2, both with all flying tailplanes. Interestingly we
once compared the Nimbus 2 tailplane to that belonging
to an adjacent Standard Cirrus in the workshop during
a C of A and found they were exactly the same. The
Nimbus has a much longer tail boom though. The tailplane
usually either goes on properly, or jams in the up
position if you fail to engage the elevator drive hook,
so it is obvious if you have got it wrong. As for all
types a positive control check is recommended before
flight.

The Nimbus was definitely the twitchier of the two
types as it seemed to suffer from aero-elasticity,
i.e. if you pulled back on the stick the wings bent
up first and then the fuselage followed about a second
later. Nevertheless I found it quite easy to fly and
even did some cloud climbs in it.

By comparison the Standard Cirrus was very easy to
fly, subject to the usual provisos for all-flying tailplanes.
Don't be put off this lovely glider by all the scare
stories!

Derek Copeland
-------------------------

At 00:00 21 March 2006, Robert Hart wrote:
Jeff Runciman wrote:
Thank you for all of your help.

It turns out the ASW is 50,000. The Cirrus makes
me
a bit nervous with the tail (attaching and flying)

I've not had much to do with Cirrus's - but I have
had to deal with the
same all flying tail plane on a borrowed Nimbus 2 whilst
my 2c was in
for repairs (see
http://www.hart.wattle.id.au/alice/a...ice3mar04.html).

I too was somewhat twitched at the stories I had heard
about the all
flying tail and its sensitivity, so my first launch
had me waiting in
some apprehension - which was completely unwarranted.

Whilst the all flying tail does mean that you shouldn't
let go off the
stick at high speed (or even for long at low speed)
it does not make the
aircraft unstable in pitch. It's certainly more sensitive
in pitch and
PIOs are easier to do - but remember a PIO is a PILOT
induced
oscillation and not a problem with the aircraft!

As for rigging and making sure the elevator is correctly
attached, it is
a bit difficult at first, but after a couple of goes
it didn't present a
great problem.

I did however do an extremely careful loaded control
check as part of
the DI (get someone to hold the all flying tail to
restrict its movement
and then firmly move the control column) to ensure
that it truly was
attached and not just 'resting'!

I would suggest you don't rule out a Cirrus just because
of the
'stories' about the all flying tail. It is my experience
that these are
exaggerated - but do of course contain a kernel of
truth as noted above!

Robert

Don't overlook that Derek Copeland is large and very heavy.

C. of G. position makes a lot of difference to the feel and stability of any
glider.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Derek Copeland"
wrote in message ...

At various times I have owned a Cirrus 75 and a Nimbus
2, both with all flying tailplanes. Interestingly we
once compared the Nimbus 2 tailplane to that belonging
to an adjacent Standard Cirrus in the workshop during
a C of A and found they were exactly the same. The
Nimbus has a much longer tail boom though. The tailplane
usually either goes on properly, or jams in the up
position if you fail to engage the elevator drive hook,
so it is obvious if you have got it wrong. As for all
types a positive control check is recommended before
flight.

The Nimbus was definitely the twitchier of the two
types as it seemed to suffer from aero-elasticity,
i.e. if you pulled back on the stick the wings bent
up first and then the fuselage followed about a second
later. Nevertheless I found it quite easy to fly and
even did some cloud climbs in it.

By comparison the Standard Cirrus was very easy to
fly, subject to the usual provisos for all-flying tailplanes.
Don't be put off this lovely glider by all the scare
stories!

Derek Copeland
-------------------------

W.J. (Bill) Dean (U.K.). wrote:
Don't overlook that Derek Copeland is large and very heavy.

C. of G. position makes a lot of difference to the feel and stability of any
glider.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.



Hi Bill

You are right - My partner in the Cirrus is a lot less comfortable - he is 80kg.
Conversely, maybe that's why I (110Kg) am so comfortable in the Cirrus.

CG is deffinitely "forward" with me in front.
--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.

Er!...something about the pot calling the kettle black
Bill?

My normal weight is in the 14 to 15 stone range, but
due to an even larger and heavier syndicate partner
who fitted quite a lot of lead to the back of the Nimbus
so that he could trim it out when thermalling, I was
actually flying the Nimbus pretty close to the minimum
cockpit weight limit. Still handled OK though.

Derek Copeland
------------------------
At 13:18 21 March 2006, W.J. \bill\ Dean \u.K.\. wrote:
Don't overlook that Derek Copeland is large and very
heavy.

C. of G. position makes a lot of difference to the
feel and stability of any
glider.

W.J. (Bill) Dean (U.K.).
Remove 'ic' to reply.


'Derek Copeland'
wrote in message ...

At various times I have owned a Cirrus 75 and a Nimbus
2, both with all flying tailplanes. Interestingly
we
once compared the Nimbus 2 tailplane to that belonging
to an adjacent Standard Cirrus in the workshop during
a C of A and found they were exactly the same. The
Nimbus has a much longer tail boom though. The tailplane
usually either goes on properly, or jams in the up
position if you fail to engage the elevator drive
hook,
so it is obvious if you have got it wrong. As for
all
types a positive control check is recommended before
flight.

The Nimbus was definitely the twitchier of the two
types as it seemed to suffer from aero-elasticity,
i.e. if you pulled back on the stick the wings bent
up first and then the fuselage followed about a second
later. Nevertheless I found it quite easy to fly and
even did some cloud climbs in it.

By comparison the Standard Cirrus was very easy to
fly, subject to the usual provisos for all-flying
tailplanes.
Don't be put off this lovely glider by all the scare
stories!

Derek Copeland
-------------------------

One thing non of you guys mention is you need to replace the trim
springs on the all flying tail models.

a buddy at minden did that on his Nimbus 2.
By replacing the 70's vintage worn out stretched trim springs with new
one it changed the glider.
He could let go of the stick and it would not go divergent on him for
extended periods.

Anyone buying of flying an all flying tail Schemp anything should
replace the trim springs.

Regards

Al
http://www.gliderforum.com

Do you sell springs by any chance?

Del. C

At 18:01 21 March 2006, wrote:
One thing non of you guys mention is you need to replace
the trim
springs on the all flying tail models.

a buddy at minden did that on his Nimbus 2.
By replacing the 70's vintage worn out stretched trim
springs with new
one it changed the glider.
He could let go of the stick and it would not go divergent
on him for
extended periods.

Anyone buying of flying an all flying tail Schemp anything
should
replace the trim springs.

Regards

Al
http://www.gliderforum.com

My club has both a Jantar and Cirrus. The Jantar get's a lot more use.
It's easier to fly and has better performance than the cirrus. I would
think the jantar would be a better machine for landouts (bigger wheel and
spoilers are more effective). I wouldn't worry about a nose over. All this
being said, I prefer the cirrus over the jantar because of the big cockpit.
Some people prefer the Jantar cockpit. It all comes down too what's best
for YOU.. Go to a location that has a glider model that your interested in.
Help rig\derig, ask a bunch more questions, sit in it to see if the cockpit
will work for you... You never know, they might even let you fly it. I've
done this over the years and as a result a have several gliders on my not to
buy list!!!

charlie

"Jeff Runciman" wrote in message
...
Thank you for all of your help.

It turns out the ASW is 50,000. The Cirrus makes me
a bit nervous with the tail (attaching and flying)
Has anybody got any thoughts on the Standard Jantar?
I can live with the two piece canopy (cant be modded
in Canada because there is no experimental class).
I also understand the gear is big for bumpy off fields
although may cause it to nose over with hard braking.
Other than that I know very little. Any advise would
be appreciated.

Jeff