Compare/Contrast: CG hook on aerotow vs. CG hook on winch

Originally Posted by noel.wade

To add to the chorus:

Just my $0.02,

--Noel
P.S. The back-release of the rope is a tricky thing on the ground in
my DG-300; like others I find a bit of wheelbrake while taking up
slack and just at the beginning of the roll is an effective "cure".

Not that I can claim to be an expert or know much, but in my Pilatus manual it mentions removing part of the Tost Release to allow for Winch launches --i.e. to allow a back release (I know my Pilatus is set for Aerotow and doesn;t back release with big slack...). If the part is not removed, there is no back release. Perhaps the different experiences in the same planes is tied to how their planes and the release mechanism were set up...

Just a WAG,
Squeak

On Jun 1, 8:59*am, Mike the Strike wrote:
I'm not sure that the advice to keep hold of the release on tow would be advisable in more turbulent environments (like Arizona) where unexpected glider movement could cause an unintended release.

Mike

I've had the same thought, Mike.

When I take friends up for rides, I tell them to put their hand(s) on
their thigh(s). That way if they make any kind of reactionary grab,
they grip their leg and not an important control. I find that for
myself this technique works in turbulent conditions pretty well - keep
a hand on the thigh, preferrably near the release-handle. As part of
my pre-takeoff checklist, I practice reaching from my thigh to the
release a couple of times; so that I'm prepared in an emergency. Then
I put my hand back on my thigh. (Of course, my DG-300 makes this easy
by having the release-handle at the base of the panel, and I don't
have any flaps to deal with - so your mileage may vary).

--Noel

P.S. Bill - Thanks for the compliments! I appreciate the feedback
and comments that you and others have given on my various recent
postings. I'm still relatively new in the sport (just hit the 5 year
mark), and its nice to be able to pitch all these theories and ideas
and see everyone's different opinions and points of view. Its all
good food for thought.

Originally Posted by Eric Greenwell[_4_]

On 5/25/2012 7:31 AM, Bill D wrote:
On May 24, 10:18 pm, Eric wrote:
On 5/24/2012 7:54 PM, son_of_flubber wrote:

No, and I suggest it may make you worse at aerotowing, because you learn
to put the glider in a steep climb. "Kiting" on tow is a bad problem;
"kiting" during a winch launch is normal operation.

A pilot would have to be pretty stupid to let that happen. (Learning
is where you ADD knowledge - not replace what was already there.)
Learn winch launch - you WILL become a better pilot.

Stupid, or poorly trained, or confused in an emergency. Still, I'm not
aware that learning winch launching in any way prepares you for aero
tow. The attitude and sight picture is entirely different, and you
aren't flying formation. I've done mostly aerotows and some auto tows,
and my experience was handling the glider took a different set of
skills. A notable difference is the auto launch was easier as long as
every thing went right - it took far less corrections compared to the
aero tow.

Learning to do winch launches so you are capable of doing winch launches
is an excellent reason, but I think it's a waste of time if your goal is
learning to do aerotow with a CG hook. The winch launch simply doesn't
challenge the pilot in the same way a CG hook aero tow does.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

Agree. About the only thing winching could teach you, that you could take to aerotow, is a strong pull on the cable attached to the belly hook will tend to pitch the nose up.

With that small caveat I don't think that anything you learn from winch launching can prepare you for learning aerotow (tethered formation flying) from either a belly or a nose hook

Cheers
Colin

On Jun 1, 1:04*pm, "noel.wade" wrote:
On Jun 1, 8:59*am, Mike the Strike wrote:

I'm not sure that the advice to keep hold of the release on tow would be advisable in more turbulent environments (like Arizona) where unexpected glider movement could cause an unintended release.

Mike

I've had the same thought, Mike.

When I take friends up for rides, I tell them to put their hand(s) on
their thigh(s). *That way if they make any kind of reactionary grab,
they grip their leg and not an important control. *I find that for
myself this technique works in turbulent conditions pretty well - keep
a hand on the thigh, preferrably near the release-handle. *As part of
my pre-takeoff checklist, I practice reaching from my thigh to the
release a couple of times; so that I'm prepared in an emergency. *Then
I put my hand back on my thigh. *(Of course, my DG-300 makes this easy
by having the release-handle at the base of the panel, and I don't
have any flaps to deal with - so your mileage may vary).

--Noel

P.S. *Bill - Thanks for the compliments! *I appreciate the feedback
and comments that you and others have given on my various recent
postings. *I'm still relatively new in the sport (just hit the 5 year
mark), and its nice to be able to pitch all these theories and ideas
and see everyone's different opinions and points of view. *Its all
good food for thought.

I teach the heel of the left hand guarding the airbrake lever. That's
usually very close to the release knob. This covers two bases - open
spoiler on tow and quick release.

I transitioned from a nose-hook Blanik L-23 to my CG-hook LS1f, all on aerotow. To be honest, I don't think there is much difference on the CG hook, and I've taken off in some crosswind/gusty conditions. I'm not terribly experienced either. A buddy of mine has a CG hook on his Discus, and he had the same experience when he transitioned. Maybe some gliders are worse about weathervaning than others, but really I don't think it's as big a deal as people make it out to be.

On Thu, 31 May 2012 18:05:10 -0700 (PDT), "noel.wade"
wrote:



2) On liftoff - as you get rolling try to use forward-stick and stick-
trim to get the tailwheel off the ground as soon as your rudder is
effective. That'll give you better steering control on the remainder
of takeoff *and* put the wing at a lower angle of attack (so you won't
jump/kite as quickly).

Hi Noel,

I have to admit that I regard this technique as bad airmanship. Really
bad airmanship (for example, an LS-6 will not lift off at all with
that technique).

Let me explain:
I've often seen gliders roll behind the towplane for ages, balancing
on the main wheel, creating lots of rolling drag and bouncing all over
the place with each bump they hit. Usually lots of control deflections
to balance crosswind (a tail wheel in the air doesn't really help to
stabilize against a crosswind...), and often multiple touchdowns after
the first lift off due to PIO.

Sometimes I even see gliders with a pith attitude, effectively
creating negative lift until the pilot decides it's time to lift off.
Scary.


In my opinion it's so much easier to simply lift off with tail and
main wheel at the same time and let the glider float behind the tow
plane - once in the air, any glider is a lot easier to control, and in
my experience on grass strips the acceleration of the tow plane is
significantly better.

I fly from a 2000 ft grass strip where one really can see the
difference in the length of the takeoff run.
It doesn't make a huge difference with a light DG-300, but flying a
fully ballasted open class ship or a Duo Discus the correct technique
(liftoff at minimum speed) is usually the difference between the tow
plane being able to lift off or not (don't ask...).

One additional benefit: If the glider lifts off close to its minimum
speed, control authority of the elevator is less agressive, therefore
it's far less likely to overcontrol the glider and enter a PIO.




Be prepared to add forward stick as you come
off the ground, and don't be shy about changing your trim multiple
times on the takeoff and aerotow.

I'm a little bit puzzled why one should mess with the trim during
aerotow.
By setting the elevator trim to the recommended position for aerotow
before launch (trim forward) you get a slight nose-down stick
pressure on all the (German built) gliders I've flown, which in my
opinion is extremely effective to prevent ballooning: The glider is a
lot more likely to descent behind the tow plane if you don't pay
attention for a moment. Better be too low behind the tow plane than
too high.

In my opinion messing with the trim during aerotow is not a good idea
for an inexperienced pilot - gliders with modern trim systems like the
DG-300 cannot be trimmed nose-down at all (as you have probably
noticed in your 300, it needs a significant stick push which isn't the
best idea if you want to keep your position behind the towplane).

Make one mistake, and you have a neutrally or even nose-up trimmed
glider - one further mistake and you might create brown pants in that
tow plane in front of you that is just disappearing under the nose of
your glider.



3) Throughout the launch and aerotow - USE YOUR FEET!

Indeed. Always. And ignore that yaw string.

But I again
have found many newbies recently that don't think to use their feet on
aerotow.

Clear case of bad training. One needs to learn to actively fly the
glider during an aerotow, otherwise problems are pre-programmed.




Best wishes
Andreas

At 15:59 01 June 2012, Mike the Strike wrote:
I'm not sure that the advice to keep hold of the release on tow would be
advisable in more turbulent environments (like Arizona) where unexpected
glider movement could cause an unintended release.

Mike

Should have made it clear, it is only necessary to have your hand on the
release during the ground run and take off for both aerotow and winch
launch, once airborne and stable you can just keep your hand near the
release as normal. I use the looped paracord so I have some slack in the
sytem anyway.

All the concern about nose vs. CG release and the correcting force of the
nose release indicates, to me, poorly trained or lazy pilots. If you will
simply fly the aircraft and pay attention to your flight path, you'll find
that it makes no difference what type of release you have (unless you're
doing a ground launch).

Do some of you actually rely on the nose release to keep the nose aligned
rather than flying the aircraft?


"Andreas Maurer" wrote in message
...
On Thu, 31 May 2012 18:05:10 -0700 (PDT), "noel.wade"
wrote:



2) On liftoff - as you get rolling try to use forward-stick and stick-
trim to get the tailwheel off the ground as soon as your rudder is
effective. That'll give you better steering control on the remainder
of takeoff *and* put the wing at a lower angle of attack (so you won't
jump/kite as quickly).

Hi Noel,

I have to admit that I regard this technique as bad airmanship. Really
bad airmanship (for example, an LS-6 will not lift off at all with
that technique).

Let me explain:
I've often seen gliders roll behind the towplane for ages, balancing
on the main wheel, creating lots of rolling drag and bouncing all over
the place with each bump they hit. Usually lots of control deflections
to balance crosswind (a tail wheel in the air doesn't really help to
stabilize against a crosswind...), and often multiple touchdowns after
the first lift off due to PIO.

Sometimes I even see gliders with a pith attitude, effectively
creating negative lift until the pilot decides it's time to lift off.
Scary.


In my opinion it's so much easier to simply lift off with tail and
main wheel at the same time and let the glider float behind the tow
plane - once in the air, any glider is a lot easier to control, and in
my experience on grass strips the acceleration of the tow plane is
significantly better.

I fly from a 2000 ft grass strip where one really can see the
difference in the length of the takeoff run.
It doesn't make a huge difference with a light DG-300, but flying a
fully ballasted open class ship or a Duo Discus the correct technique
(liftoff at minimum speed) is usually the difference between the tow
plane being able to lift off or not (don't ask...).

One additional benefit: If the glider lifts off close to its minimum
speed, control authority of the elevator is less agressive, therefore
it's far less likely to overcontrol the glider and enter a PIO.




Be prepared to add forward stick as you come
off the ground, and don't be shy about changing your trim multiple
times on the takeoff and aerotow.

I'm a little bit puzzled why one should mess with the trim during
aerotow.
By setting the elevator trim to the recommended position for aerotow
before launch (trim forward) you get a slight nose-down stick
pressure on all the (German built) gliders I've flown, which in my
opinion is extremely effective to prevent ballooning: The glider is a
lot more likely to descent behind the tow plane if you don't pay
attention for a moment. Better be too low behind the tow plane than
too high.

In my opinion messing with the trim during aerotow is not a good idea
for an inexperienced pilot - gliders with modern trim systems like the
DG-300 cannot be trimmed nose-down at all (as you have probably
noticed in your 300, it needs a significant stick push which isn't the
best idea if you want to keep your position behind the towplane).

Make one mistake, and you have a neutrally or even nose-up trimmed
glider - one further mistake and you might create brown pants in that
tow plane in front of you that is just disappearing under the nose of
your glider.



3) Throughout the launch and aerotow - USE YOUR FEET!

Indeed. Always. And ignore that yaw string.

But I again
have found many newbies recently that don't think to use their feet on
aerotow.

Clear case of bad training. One needs to learn to actively fly the
glider during an aerotow, otherwise problems are pre-programmed.




Best wishes
Andreas

At 16:12 02 June 2012, Dan Marotta wrote:
All the concern about nose vs. CG release and the correcting force of the

nose release indicates, to me, poorly trained or lazy pilots. If you will

simply fly the aircraft and pay attention to your flight path, you'll find

that it makes no difference what type of release you have (unless you're
doing a ground launch).

[snip]

The concern in the UK about towing on CG hook when a nose hook is available
came from tug pilot fatalities. The first, and most of the other, such
accidents happened with CG hooks, and one or more of the other factors,
which led to kiting, tug upset, and tug hitting the deck. As a result, the
BGA issued a poster listing the 6 factors most closely associated with
upsets, and advised having not more that two (IIRC) such factors on any one
launch.

More recently we started to have upsets again, so far fortunately without
fatality. Unable to find the original poster, we issued another which had
the following:
-------------------
Tug Upsets

These happen when the glider suddenly zooms above the tug, putting it into
a steep dive requiring considerable height to recover.

The BGA ran a successful campaign to end these fatalities to tug pilots,
but several years without incident now appear to have ended. This year
there have been two reported upsets and at least one other not reported.
Fortunately none resulted in crashes.

Six factors make upsets more likely:

 Lightweight, low wing-loading

 C of G hooks intended for winch launching

 Short ropes

 Inexperienced pilots

 Near aft C of G.

 Turbulent conditions

If two of these are present the danger becomes significant. More than
two should be considered unacceptable.

-----------------
Chris N

On 6/1/2012 5:11 PM, dbrunone wrote:
I transitioned from a nose-hook Blanik L-23 to my CG-hook LS1f, all on
aerotow. To be honest, I don't think there is much difference on the CG
hook, and I've taken off in some crosswind/gusty conditions. I'm not
terribly experienced either. A buddy of mine has a CG hook on his
Discus, and he had the same experience when he transitioned. Maybe some
gliders are worse about weathervaning than others, but really I don't
think it's as big a deal as people make it out to be.

It may depend a great deal on the glider (some get aerodynamic control
sooner than others) and your launch conditions: if every launch uses an
experienced wing runner, a strong towplane, and the wind is always
straight down the runway, you will not notice much difference.

All the nose-hook gliders (primarily H301, ASH 26 E, and ASW20C) I've
flown were easier to aerotow than all the CG hook gliders (primarily
Ka6e, Std Cirrus, and ASW20C) I've flown. The ASW20C was a special case:
it came with a CG hook that I used for several years, then I had a nose
(actually, a "forward") hook installed. It was a noticeable and
significant improvement over the original CG hook.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)