Much Ado About Nothing

[Dan Marotta]

To lift a title from The Bard and, since there's not much else going on
these days, and to give homage to Roseanne Roseannadana...

What's all this nonsense I keep hearing about CG hooks?

My first glider had a nose hook and it was easy to control on launch and
tow.Â* All the rest had CG hooks (only) and I never noticed a difference
either on take off or tow.Â* The only advantage I ever noticed about
either was on ground launch where the nose hook was at a distinct
disadvantage.

So, for me at least, a CG hook would be a must for any non-self-launch
glider.Â* I think that those who make a big bugaboo about CG hooks are
doing a disservice to gliding.

Let the games begin...

--
Dan, 5J

[[email protected]]

"I never noticed a difference either on take off or tow."

I don't agree, CG is more pleasing to fly on tow. Since there is little torque on the glider from the cable, a CG hook provides more options for holding position.

The CG hook is also quite stable (as in stick won't help) in a nose high, cable low, elevator stalled configuration. Which is fine unless you happen to be tied a tow plane also with a stalled elevator at the time. This is extremely unlikely to happen if the glider pilot understands the possibility and proactively doesn't go there. Sadly, we sometimes don't include this possibility in training and so it does happen.

Game on

[Dan Marotta]

Well put.Â* Let's hear from the opposition.

On 3/28/2020 10:16 AM, wrote:
> "I never noticed a difference either on take off or tow."
>
> I don't agree, CG is more pleasing to fly on tow. Since there is little torque on the glider from the cable, a CG hook provides more options for holding position.
>
> The CG hook is also quite stable (as in stick won't help) in a nose high, cable low, elevator stalled configuration. Which is fine unless you happen to be tied a tow plane also with a stalled elevator at the time. This is extremely unlikely to happen if the glider pilot understands the possibility and proactively doesn't go there. Sadly, we sometimes don't include this possibility in training and so it does happen.
>
> Game on

--
Dan, 5J

[Tango Eight]

On Saturday, March 28, 2020 at 12:16:05 PM UTC-4, wrote:
> "I never noticed a difference either on take off or tow."
>
> I don't agree, CG is more pleasing to fly on tow. Since there is little torque on the glider from the cable, a CG hook provides more options for holding position.
>
> The CG hook is also quite stable (as in stick won't help) in a nose high, cable low, elevator stalled configuration. Which is fine unless you happen to be tied a tow plane also with a stalled elevator at the time. This is extremely unlikely to happen if the glider pilot understands the possibility and proactively doesn't go there. Sadly, we sometimes don't include this possibility in training and so it does happen.
>
> Game on

It's night time in Australia, guys :-).

Nose hook for aero tow is a JAR thing now, and unlikely to change. It's my view that a (well designed and located) nose hook is safest for aero tow.

Some CG only gliders are pussycats on tow, have perfect manners.

Some nose hook equipped gliders have dangerous pitching tendencies.

Inattentive glider pilots have killed tow pilots with both types.

200' tow rope (or longer) and Tost release on both ends is good.

Switched on pilots with good training and procedures is best.

T8

[Eric Greenwell[_4_]]

wrote on 3/28/2020 9:16 AM:
> "I never noticed a difference either on take off or tow."
>
> I don't agree, CG is more pleasing to fly on tow. Since there is little torque on the glider from the cable, a CG hook provides more options for holding position.
>
> The CG hook is also quite stable (as in stick won't help) in a nose high, cable low, elevator stalled configuration. Which is fine unless you happen to be tied a tow plane also with a stalled elevator at the time. This is extremely unlikely to happen if the glider pilot understands the possibility and proactively doesn't go there. Sadly, we sometimes don't include this possibility in training and so it does happen.
>
> Game on

I've owned three gliders with CG hooks, and three with nose hooks. The nose hooks
went straighter on the take off roll, ESPECIALLY during an unassisted launch. All
were easier to manage in the air, requiring less attention, particularly in
turbulent conditions. The only position I cared about holding was behind the towplane.

My ASW20C came with a CG hook; years later, I had a "forward" hook added (about 2'
from the nose). The difference was significant, and I was glad I spent the money.
Most of my launches were unassisted, and I was pleased I could handle crosswinds
better.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[Charlie M. (UH & 002 owner/pilot)]

Hmmm.....many years, "a bit of sailplane hours"......a lot of "Mercian iron" (SGS) with nose hooks, about the same hours with CG hooks (mostly AS**** ships)..... all aero tow...frankly, in lots of conditions and suitable training, can't say I have an issue or preference.
Yes, low time training, nose hook can help since it tends to track to towplane tail a little easier.
Yes, most of my aerotow hours are low tow (please don't start that argument yet again here....I fly and trained on both...).
:-(

I have NO winch experience (would LOVE to do Karl's course in PA....if nothing more than to fly with Karl...;-)).

[Michael Opitz]

At 15:28 28 March 2020, Dan Marotta wrote:
>To lift a title from The Bard and, since there's not much else going
on
>these days, and to give homage to Roseanne Roseannadana...
>
>What's all this nonsense I keep hearing about CG hooks?
>
>My first glider had a nose hook and it was easy to control on
launch and
>tow.Â* All the rest had CG hooks (only) and I never noticed a
difference
>either on take off or tow.Â* The only advantage I ever noticed about
>either was on ground launch where the nose hook was at a distinct
>disadvantage.
>
>So, for me at least, a CG hook would be a must for any non-self-
launch
>glider.Â* I think that those who make a big bugaboo about CG hooks
are
>doing a disservice to gliding.
>
>Let the games begin...
>
>--
>Dan, 5J
>

The issue came up back in the early 1980's when most all high
performance gliders only had C/G hooks for drag reduction
purposes. A lot of those gliders still had tail skids as well. Stack
a bunch of them on a paved runway for a competition and watch
out! With any kind of crosswind at all, the gliders didn't have
enough rudder authority at low speed to counter impending ground
loops with any kind of weathervaning at all. Add a wing drop due
to uneven tow plane prop vortices, and we had all sorts of ground
loops into other gliders, cars and people on the sidelines. Using
dive brakes to kill the lift on both wings on initial take-off roll helped

with the wing drop issues, but until tail wheels became the norm,
the tail skids would not track well on a hard surface. This lack of tail
tracking ability coupled with a C/G release location meant that once
a little weathervaning started, there was no way to stop it until you
had rudder authority, and a lot of times, that was too late. The nose
hook always pulls in front of the C/G to self damp or return the nose
towards the centerline, which is extremely helpful until one gets
rudder authority. There was way too much excitement on the
contest take-off grid until tail wheels and nose hooks came to be the
norm, and that's why there is the nose hook preference on newer
gliders.

RO

[Roy B.]

I think Mike/RO has it right. The difference between CG and nose hooks is mostly felt on the ground at the beginning of the roll. If a wing goes down and the tail is not planted down hard, with a CG hook watch out. In the air there is not much difference. I've flown lots of gliders with both style hooks (and used both on aerotow), and never noticed much difference once I got in the air.
ROY

[Michael Opitz]

At 00:11 29 March 2020, Roy B. wrote:
>I think Mike/RO has it right. The difference between CG and nose
hooks is
>m=
>ostly felt on the ground at the beginning of the roll. If a wing goes
down
>=
>and the tail is not planted down hard, with a CG hook watch out. In
the
>air=
> there is not much difference. I've flown lots of gliders with both style
>h=
>ooks (and used both on aerotow), and never noticed much difference
once I
>g=
>ot in the air.
>ROY=20
>

And to the folks who say that they haven't noticed a difference, I
will bet they haven't tried taking off with full water ballast and a 10-
15 Kt crosswind at a high density altitude SW USA desert location
in a C/G hook / tail skid equipped glider... Been there, done that,
got the T-shirt, and don't care to reinvent the wheel. I, for one
have learned from history. Some of the younger folks haven't
been around long enough to have seen it for themselves.

RO

[Nick Kennedy[_3_]]

RO
I think these days tailskids are as rare as hens teeth.
The last one I saw was when the guy who bought my 1958 Ka6CR towed it home in 2000.

[Michael Opitz]

At 02:37 29 March 2020, Nick Kennedy wrote:
>RO
>I think these days tailskids are as rare as hens teeth.
>The last one I saw was when the guy who bought my 1958 Ka6CR
towed it home
>in 2000.
>
A lot of the 1980's vintage tail skids were retrofitted with the
in-line skate wheels embedded in the skid. They helped, but still
wouldn't track as well as the larger pneumatic tires. My Discus-B
and I believe my first ASW-24 still had skids.

RO

[Roy B.]

My old ASW 17 had a tail skid - and to make it worse it had a metal cleat screwed to the bottom of the skid and and the old Schleicher off center CG hook. Needless to say, SOP was to start the roll with the stick full back & a prayer if on tarmac. Once in the air it was fine.

I suspect (but am not sure) that people who report a difference in aero tow handling between belly hooks and nose hooks are really perceiving the difference between forward and aft center of gravity locations on different gliders or the effect of all flying tails. Both of those impact aero tow handling more than location of the hook, in my experience.
ROY

[WB]

301 Libelles sit high on their gear with the wings at a high angle. Takes relatively longer in the takeoff roll to get the tail up and the ailerons alive. Wing drops are an issue. My 301 is a little worse in that respect. It has Kestrel landing gear so sits about an inch higher than the norm. Towing from the nose hook helps noticeably with getting the tail up and helps prevent wing drop. Once in the air, the diff between flying the nose or belly hook is small.

[Hartley Falbaum[_2_]]

On Saturday, March 28, 2020 at 11:28:10 AM UTC-4, Dan Marotta wrote:
> To lift a title from The Bard and, since there's not much else going on
> these days, and to give homage to Roseanne Roseannadana...
>
> What's all this nonsense I keep hearing about CG hooks?
>
> My first glider had a nose hook and it was easy to control on launch and
> tow.Â* All the rest had CG hooks (only) and I never noticed a difference
> either on take off or tow.Â* The only advantage I ever noticed about
> either was on ground launch where the nose hook was at a distinct
> disadvantage.
>
> So, for me at least, a CG hook would be a must for any non-self-launch
> glider.Â* I think that those who make a big bugaboo about CG hooks are
> doing a disservice to gliding.
>
> Let the games begin...
>
> --
> Dan, 5J

Chris Rollings did actual research on kiting problems with CG and Nose hooks. Google Chris Rollings and read for yourselves.

Hartley Falbaum

[Dan Marotta]

Good historical write up, Mike, but the intent of my post was the
current fear of CG hooks.Â* Today pretty much every glider has a tail
wheel with a rubber tire and plenty of rudder authority.Â* It's the same
as the apparent fear in the US of ground launching.Â* I could start
another thread about that...

Thinking back to my first LS-6 (I owned two in partnerships), it had a
CG hook only and a funny little hard plastic tail wheel which had no
traction at all.Â* I would equate that to a skid on pavement. IIRC, it
also came with a steel plate tail skid so I guess the plastic wheel was
an improvement, but much.Â* My solution was not to install a nose hook,
but to replace the plastic wheel with a roller blade tire (all of $3
used).Â* Worked like a champ and I never ground looped the ship.Â* Neither
did my partner.

Oh, and we did a boat load of ground launches in that ship. Something
that would not have been too much fun with a nose hook.

On 3/28/2020 3:13 PM, Michael Opitz wrote:
> At 15:28 28 March 2020, Dan Marotta wrote:
>> To lift a title from The Bard and, since there's not much else going
> on
>> these days, and to give homage to Roseanne Roseannadana...
>>
>> What's all this nonsense I keep hearing about CG hooks?
>>
>> My first glider had a nose hook and it was easy to control on
> launch and
>> tow.ÂÂ* All the rest had CG hooks (only) and I never noticed a
> difference
>> either on take off or tow.ÂÂ* The only advantage I ever noticed about
>> either was on ground launch where the nose hook was at a distinct
>> disadvantage.
>>
>> So, for me at least, a CG hook would be a must for any non-self-
> launch
>> glider.ÂÂ* I think that those who make a big bugaboo about CG hooks
> are
>> doing a disservice to gliding.
>>
>> Let the games begin...
>>
>> --
>> Dan, 5J
>>
>
> The issue came up back in the early 1980's when most all high
> performance gliders only had C/G hooks for drag reduction
> purposes. A lot of those gliders still had tail skids as well. Stack
> a bunch of them on a paved runway for a competition and watch
> out! With any kind of crosswind at all, the gliders didn't have
> enough rudder authority at low speed to counter impending ground
> loops with any kind of weathervaning at all. Add a wing drop due
> to uneven tow plane prop vortices, and we had all sorts of ground
> loops into other gliders, cars and people on the sidelines. Using
> dive brakes to kill the lift on both wings on initial take-off roll helped
>
> with the wing drop issues, but until tail wheels became the norm,
> the tail skids would not track well on a hard surface. This lack of tail
> tracking ability coupled with a C/G release location meant that once
> a little weathervaning started, there was no way to stop it until you
> had rudder authority, and a lot of times, that was too late. The nose
> hook always pulls in front of the C/G to self damp or return the nose
> towards the centerline, which is extremely helpful until one gets
> rudder authority. There was way too much excitement on the
> contest take-off grid until tail wheels and nose hooks came to be the
> norm, and that's why there is the nose hook preference on newer
> gliders.
>
> RO
>

--
Dan, 5J

[Jonathan St. Cloud]

On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz wrote:
> At 02:37 29 March 2020, Nick Kennedy wrote:
> >RO
> >I think these days tailskids are as rare as hens teeth.
> >The last one I saw was when the guy who bought my 1958 Ka6CR
> towed it home
> >in 2000.
> >
> A lot of the 1980's vintage tail skids were retrofitted with the
> in-line skate wheels embedded in the skid. They helped, but still
> wouldn't track as well as the larger pneumatic tires. My Discus-B
> and I believe my first ASW-24 still had skids.
>
> RO

Your ASW-24 didd not have a skid. But they were still a handful even without a load of water, with a quartering tailwind at start of roll. An ASW-24 with CG hook is the only glider I have released on tow on the ground for control issues. I did aerotow my ASH26 a multiple times with the gear mounted CG hook, that was much nicer than the ASW-24 CG hook.

[Eric Greenwell[_4_]]

Jonathan St. Cloud wrote on 3/29/2020 10:17 AM:
> On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz wrote:
>> At 02:37 29 March 2020, Nick Kennedy wrote:
>>> RO
>>> I think these days tailskids are as rare as hens teeth.
>>> The last one I saw was when the guy who bought my 1958 Ka6CR
>> towed it home
>>> in 2000.
>>>
>> A lot of the 1980's vintage tail skids were retrofitted with the
>> in-line skate wheels embedded in the skid. They helped, but still
>> wouldn't track as well as the larger pneumatic tires. My Discus-B
>> and I believe my first ASW-24 still had skids.
>>
>> RO
>
> Your ASW-24 didd not have a skid. But they were still a handful even without a load of water, with a quartering tailwind at start of roll. An ASW-24 with CG hook is the only glider I have released on tow on the ground for control issues. I did aerotow my ASH26 a multiple times with the gear mounted CG hook, that was much nicer than the ASW-24 CG hook.
>

Did your ASH26 have a steerable tail wheel? That makes a tremendous difference in
controlling where you want it to go. Even without that, the designer's deliberate
positioning of the main gear more forward than usual puts considerable weight on
the tail wheel, increasing it's authority, and making the glider much less likely
to swerve.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[Michael Opitz]

At 17:17 29 March 2020, Jonathan St. Cloud wrote:
>On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz
wrote:
>> At 02:37 29 March 2020, Nick Kennedy wrote:
>> >RO
>> >I think these days tailskids are as rare as hens teeth.
>> >The last one I saw was when the guy who bought my 1958
Ka6CR=20
>> towed it home
>> >in 2000.
>> >
>> A lot of the 1980's vintage tail skids were retrofitted with the
>> in-line skate wheels embedded in the skid. They helped, but still
>> wouldn't track as well as the larger pneumatic tires. My Discus-
B=20
>> and I believe my first ASW-24 still had skids.=20
>>=20
>> RO
>
>Your ASW-24 didd not have a skid. But they were still a handful
even
>witho=
>ut a load of water, with a quartering tailwind at start of roll. An
>ASW-2=
>4 with CG hook is the only glider I have released on tow on the
ground for
>=
>control issues. I did aerotow my ASH26 a multiple times with the
gear
>moun=
>ted CG hook, that was much nicer than the ASW-24 CG hook.
>

Jon,

My first ASW-24 was serial #10. I checked some old pictures, and
it had a tail skid. I may have gotten a tail wheel on my second
one, But I can't remember right now.

RO

[Bob Youngblood]

On Saturday, March 28, 2020 at 11:28:10 AM UTC-4, Dan Marotta wrote:
> To lift a title from The Bard and, since there's not much else going on
> these days, and to give homage to Roseanne Roseannadana...
>
> What's all this nonsense I keep hearing about CG hooks?
>
> My first glider had a nose hook and it was easy to control on launch and
> tow.Â* All the rest had CG hooks (only) and I never noticed a difference
> either on take off or tow.Â* The only advantage I ever noticed about
> either was on ground launch where the nose hook was at a distinct
> disadvantage.
>
> So, for me at least, a CG hook would be a must for any non-self-launch
> glider.Â* I think that those who make a big bugaboo about CG hooks are
> doing a disservice to gliding.
>
> Let the games begin...
>
> --
> Dan, 5J

Well, I like the CG hook, I use it all the time even on self launches. I think I should write a book called, Nose Hooks For Idiots. Bob

[[email protected]]

On Sunday, March 29, 2020 at 4:15:04 PM UTC-4, Michael Opitz wrote:
> At 17:17 29 March 2020, Jonathan St. Cloud wrote:
> >On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz
> wrote:
> >> At 02:37 29 March 2020, Nick Kennedy wrote:
> >> >RO
> >> >I think these days tailskids are as rare as hens teeth.
> >> >The last one I saw was when the guy who bought my 1958
> Ka6CR=20
> >> towed it home
> >> >in 2000.
> >> >
> >> A lot of the 1980's vintage tail skids were retrofitted with the
> >> in-line skate wheels embedded in the skid. They helped, but still
> >> wouldn't track as well as the larger pneumatic tires. My Discus-
> B=20
> >> and I believe my first ASW-24 still had skids.=20
> >>=20
> >> RO
> >
> >Your ASW-24 didd not have a skid. But they were still a handful
> even
> >witho=
> >ut a load of water, with a quartering tailwind at start of roll. An
> >ASW-2=
> >4 with CG hook is the only glider I have released on tow on the
> ground for
> >=
> >control issues. I did aerotow my ASH26 a multiple times with the
> gear
> >moun=
> >ted CG hook, that was much nicer than the ASW-24 CG hook.
> >
>
> Jon,
>
> My first ASW-24 was serial #10. I checked some old pictures, and
> it had a tail skid. I may have gotten a tail wheel on my second
> one, But I can't remember right now.
>
> RO

I'll bet your skid was probably a plug in into the tail wheel mount for "low drag".
My '27 came back from a nationals with a skid> I asked the guy I loaned it to "what were you thinking?" He said "low drag".
Sigh
UH

[Jonathan St. Cloud]

On Sunday, March 29, 2020 at 1:15:04 PM UTC-7, Michael Opitz wrote:
> At 17:17 29 March 2020, Jonathan St. Cloud wrote:
> >On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz
> wrote:
> >> At 02:37 29 March 2020, Nick Kennedy wrote:
> >> >RO
> >> >I think these days tailskids are as rare as hens teeth.
> >> >The last one I saw was when the guy who bought my 1958
> Ka6CR=20
> >> towed it home
> >> >in 2000.
> >> >
> >> A lot of the 1980's vintage tail skids were retrofitted with the
> >> in-line skate wheels embedded in the skid. They helped, but still
> >> wouldn't track as well as the larger pneumatic tires. My Discus-
> B=20
> >> and I believe my first ASW-24 still had skids.=20
> >>=20
> >> RO
> >
> >Your ASW-24 didd not have a skid. But they were still a handful
> even
> >witho=
> >ut a load of water, with a quartering tailwind at start of roll. An
> >ASW-2=
> >4 with CG hook is the only glider I have released on tow on the
> ground for
> >=
> >control issues. I did aerotow my ASH26 a multiple times with the
> gear
> >moun=
> >ted CG hook, that was much nicer than the ASW-24 CG hook.
> >
>
> Jon,
>
> My first ASW-24 was serial #10. I checked some old pictures, and
> it had a tail skid. I may have gotten a tail wheel on my second
> one, But I can't remember right now.
>
> RO

My mistake, I was under the impression they were never made with a skid. I owned two different ASW-24's also. Nice bird

[Jonathan St. Cloud]

On Sunday, March 29, 2020 at 11:06:14 AM UTC-7, Eric Greenwell wrote:
> Jonathan St. Cloud wrote on 3/29/2020 10:17 AM:
> > On Saturday, March 28, 2020 at 8:15:05 PM UTC-7, Michael Opitz wrote:
> >> At 02:37 29 March 2020, Nick Kennedy wrote:
> >>> RO
> >>> I think these days tailskids are as rare as hens teeth.
> >>> The last one I saw was when the guy who bought my 1958 Ka6CR
> >> towed it home
> >>> in 2000.
> >>>
> >> A lot of the 1980's vintage tail skids were retrofitted with the
> >> in-line skate wheels embedded in the skid. They helped, but still
> >> wouldn't track as well as the larger pneumatic tires. My Discus-B
> >> and I believe my first ASW-24 still had skids.
> >>
> >> RO
> >
> > Your ASW-24 didd not have a skid. But they were still a handful even without a load of water, with a quartering tailwind at start of roll. An ASW-24 with CG hook is the only glider I have released on tow on the ground for control issues. I did aerotow my ASH26 a multiple times with the gear mounted CG hook, that was much nicer than the ASW-24 CG hook.
> >
>
> Did your ASH26 have a steerable tail wheel? That makes a tremendous difference in
> controlling where you want it to go. Even without that, the designer's deliberate
> positioning of the main gear more forward than usual puts considerable weight on
> the tail wheel, increasing it's authority, and making the glider much less likely
> to swerve.
>
>
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> - "A Guide to Self-Launching Sailplane Operation"
> https://sites.google.com/site/motorgliders/publications/download-the-guide-1

No, my ASH26 did not have the steerable installed at time of aero tows. None of the low speed T/O issues my ASW-24's could have with the CG hook.