Does anyone use a tug tow hook that releases automatically whenglider kites?

The time difference to go from low tow to kiting compared to high tow to
kiting is about 1 second - try it at safe altitude. As observed you can't
take-off in low tow so the highest risk time, just after take off when the
combination is accelerating, is exactly the same. The transition from
normal tow to low tow, early in the climb, puts the glider into the
turbulence of the prop-wash which may well cause the, less than one second,
loss of control which is all that is needed to start the kiting. Finally,
low tow on a glider with a C of G hook, leaves the rope wrapped around the
side of the cockpit, not really a good idea and C of G hooks are where the
danger lies.

The cheapest mechanical solution is, fit a nose hook to any glider that is
going to be aerotowed.

My best estimate of low level kiting fatal/serious accident frequency is of
the order of one in a million. "Tens of thousands of aerotows" is not a
big enough sample to draw conclusions.

At 07:58 22 February 2014, GC wrote:
On 22/02/2014 16:17, Alan wrote:

...You don't get kiting if you fly normal "high" tow behind the
towplane,
if you remain in control.

If you don't remain in control, starting from low tow is not going
to
make a lot of difference.

Experience (tens of thousands of aerotows) shows there is an enormous
difference. The inadequate control and time to go from high tow to
kiting is orders of magnitude different from that required to go from
low tow to kiting. In fact, I've never heard of that ever happening.
Even with low time students. Kiting from high tow, however, is
apparently so common as to need a whole new system of electronic
whizzbangery and gallons of bandwidth to stop.

If the tug has just lifted off, being in low tow sounds a bit
difficult,
but that would be a particularly hazardous time.

Yes. Liftoff is a time to be wary and we train accordingly.
Nevertheless, all I can say is that low tow has prevented kiting
accidents for many years. But don't take my word for it, keep this
ridiculous discussion going with another screwball idea for pivoting,
autoswivelling, pitch-sensing, stick-following nonsense.

If the issue is serious - as it was in Australia - flying low tow will
solve it. If it isn't - see my previous post.

GC



As for automatic methods to mitigate the problem, perhaps the
solution
is not to modify tow planes, but to modify gliders. If the glider is
in a very high pitch attitude on tow, it might be a good time to
automatically
release.

Another modification might be to attach the tow rope to the top of
the
glider.
This would cause the tow force to pitch the glider down.


Is this more of a problem when folks try to tow a slow glider like a
2-33 at
high speeds?

Alan

On 22/02/2014 20:21, Chris Rollings wrote:
The time difference to go from low tow to kiting compared to high tow to
kiting is about 1 second - try it at safe altitude.

I read your posts carefully, Chris and I don't recall any low tow
experiments. The closest was your description of the glider with the
PA-18 as "in a slightly low normal tow position" which I take to be high
tow for you. So I don't think you speak with any special authority on
low tow. Correct me if I'm wrong. I have a lot of experience with low
tow and your 1 second is wrong unless a normally competent pilot intends
- suicidally - to deliberately go kiting. To use your own words: it's
"...something unlikely to occur accidentally, even with an inexperienced
glider pilot."

...As observed you can't
take-off in low tow so the highest risk time, just after take off when the
combination is accelerating, is exactly the same.

....and no worse. And needs the same training whether it ends in high or
low tow.

The transition from
normal tow to low tow, early in the climb, puts the glider into the
turbulence of the prop-wash which may well cause the, less than one second,
loss of control which is all that is needed to start the kiting.

You originally said 2 to 3 seconds from high tow so it's got to be at
least 4 seconds from low tow on your own figures above - but we won't
quibble about trivia. All I can say is that it's not our - very
considerable - experience. You're welcome to learn nothing from anybody
else (a very English habit, that) but in that case let's drop the
pretence that kiting is a seriously difficult problem to solve and
worthy of vast quantities of speculative rubbish.

Finally,
low tow on a glider with a C of G hook, leaves the rope wrapped around the
side of the cockpit, not really a good idea and C of G hooks are where the
danger lies.
The cheapest mechanical solution is, fit a nose hook to any glider that is
going to be aerotowed.

That's why aerotow is only permitted on nose hooks in Oz. It's the
obvious counterpart of low tow. You don't travel much, do you? I have
done low tows on a CG hook (at Hus Bos) and they were a non-event.

My best estimate of low level kiting fatal/serious accident frequency is of
the order of one in a million. "Tens of thousands of aerotows" is not a
big enough sample to draw conclusions.

Mmm. Statistics aren't your strong point, are they Chris?

I must say I'm quite stunned by your negativity re low tow, especially
if you were once CFI at Booker. I read and was impressed by your tests.
You seemed to take the problem really seriously. This is the reality:
there is a simple solution (not perfect) available immediately to
minimise the risk of kiting. If it's a serious problem, it should be
implemented while the fancy gimcrackery is developed and I'm surprised
you're fighting it. Otherwise, it's not a problem you actually take all
that seriously. As you said, one in a million. Australia thinks it's
serious enough to have actually done something. It appears you don't.
That's fair enough, it's your call, so let's forget all the bull**** and
talk about something else.

GC


At 07:58 22 February 2014, GC wrote:
On 22/02/2014 16:17, Alan wrote:

...You don't get kiting if you fly normal "high" tow behind the
towplane,
if you remain in control.

If you don't remain in control, starting from low tow is not going
to
make a lot of difference.

Experience (tens of thousands of aerotows) shows there is an enormous
difference. The inadequate control and time to go from high tow to
kiting is orders of magnitude different from that required to go from
low tow to kiting. In fact, I've never heard of that ever happening.
Even with low time students. Kiting from high tow, however, is
apparently so common as to need a whole new system of electronic
whizzbangery and gallons of bandwidth to stop.

If the tug has just lifted off, being in low tow sounds a bit
difficult,
but that would be a particularly hazardous time.

Yes. Liftoff is a time to be wary and we train accordingly.
Nevertheless, all I can say is that low tow has prevented kiting
accidents for many years. But don't take my word for it, keep this
ridiculous discussion going with another screwball idea for pivoting,
autoswivelling, pitch-sensing, stick-following nonsense.

If the issue is serious - as it was in Australia - flying low tow will
solve it. If it isn't - see my previous post.

GC



As for automatic methods to mitigate the problem, perhaps the
solution
is not to modify tow planes, but to modify gliders. If the glider is
in a very high pitch attitude on tow, it might be a good time to
automatically
release.

Another modification might be to attach the tow rope to the top of
the
glider.
This would cause the tow force to pitch the glider down.


Is this more of a problem when folks try to tow a slow glider like a
2-33 at
high speeds?

Alan

On Saturday, February 22, 2014 4:21:55 AM UTC-5, Chris Rollings wrote:

The cheapest mechanical solution is, fit a nose hook to any glider that is
going to be aerotowed.

Does the record support this? Are all the fatal kiting incidents connected to a CG hook on the glider? Has there ever been a fatal kiting incident connected to a glider nose hook?

Aren't new gliders required to have a nose hook for aerotow?

On Saturday, February 22, 2014 1:58:28 AM UTC-6, GC wrote:
On 22/02/2014 16:17, Alan wrote:



...You don't get kiting if you fly normal "high" tow behind the towplane,

if you remain in control.



If you don't remain in control, starting from low tow is not going to

make a lot of difference.



Experience (tens of thousands of aerotows) shows there is an enormous

difference. The inadequate control and time to go from high tow to

kiting is orders of magnitude different from that required to go from

low tow to kiting. In fact, I've never heard of that ever happening.

Even with low time students. Kiting from high tow, however, is

apparently so common as to need a whole new system of electronic

whizzbangery and gallons of bandwidth to stop.



If the tug has just lifted off, being in low tow sounds a bit difficult,

but that would be a particularly hazardous time.



Yes. Liftoff is a time to be wary and we train accordingly.

Nevertheless, all I can say is that low tow has prevented kiting

accidents for many years. But don't take my word for it, keep this

ridiculous discussion going with another screwball idea for pivoting,

autoswivelling, pitch-sensing, stick-following nonsense.



If the issue is serious - as it was in Australia - flying low tow will

solve it. If it isn't - see my previous post.



GC







As for automatic methods to mitigate the problem, perhaps the solution

is not to modify tow planes, but to modify gliders. If the glider is

in a very high pitch attitude on tow, it might be a good time to automatically

release.



Another modification might be to attach the tow rope to the top of the glider.

This would cause the tow force to pitch the glider down.





Is this more of a problem when folks try to tow a slow glider like a 2-33 at

high speeds?



Alan


GC is making his point for low tows very convincingly - why is he immediately being ripped, Chris? Preparing and steering into low tow at a safe altitude, say 300', means to mentally and then practically pushing the stick forward and then holding in the low tow position. That's the opposite maneuver of what's leading to kiting. Drifting upwards takes you into the prop wash and again, it takes forward stick pressure to move into the safe spot. That feedback mechanism is correctly maintaining the intended safe spot while in the normal tow position only visual cues are being used.
I think I'll give the low tow a try, if ever that polar vortex over Chicago makes like tree...
Herb

At 14:28 22 February 2014, wrote:
On Saturday, February 22, 2014 1:58:28 AM UTC-6, GC wrote:
On 22/02/2014 16:17, Alan wrote:
=20
=20
=20
...You don't get kiting if you fly normal "high" tow behind the
towplan=
e,
=20
if you remain in control.
=20

=20
If you don't remain in control, starting from low tow is not going
t=
o
=20
make a lot of difference.
=20
=20
=20
Experience (tens of thousands of aerotows) shows there is an
enormous=20
=20
difference. The inadequate control and time to go from high tow to=20
=20
kiting is orders of magnitude different from that required to go
from=20
=20
low tow to kiting. In fact, I've never heard of that ever
happening.=20
=20
Even with low time students. Kiting from high tow, however, is=20
=20
apparently so common as to need a whole new system of electronic=20
=20
whizzbangery and gallons of bandwidth to stop.
=20
=20
=20
If the tug has just lifted off, being in low tow sounds a bit
diffic=
ult,
=20
but that would be a particularly hazardous time.
=20
=20
=20
Yes. Liftoff is a time to be wary and we train accordingly.=20
=20
Nevertheless, all I can say is that low tow has prevented kiting=20
=20
accidents for many years. But don't take my word for it, keep this=20
=20
ridiculous discussion going with another screwball idea for
pivoting,=20
=20
autoswivelling, pitch-sensing, stick-following nonsense.
=20
=20
=20
If the issue is serious - as it was in Australia - flying low tow
will=20
=20
solve it. If it isn't - see my previous post.
=20
=20
=20
GC
=20
=20
=20

=20

=20
As for automatic methods to mitigate the problem, perhaps the
soluti=
on
=20
is not to modify tow planes, but to modify gliders. If the glider is
=20
in a very high pitch attitude on tow, it might be a good time to
automa=
tically
=20
release.
=20

=20
Another modification might be to attach the tow rope to the top of
t=
he glider.
=20
This would cause the tow force to pitch the glider down.
=20

=20

=20
Is this more of a problem when folks try to tow a slow glider like
a=
2-33 at
=20
high speeds?
=20

=20
Alan
=20

GC is making his point for low tows very convincingly - why is he
immediate=
ly being ripped, Chris? Preparing and steering into low tow at a safe
alti=
tude, say 300',

If you wait 'till 300 feet the majority of the risk of a fatal kiting
incident is already behind you, once past 400 feet there is just about
enough height for the tow pilot to recover.

means to mentally and then practically pushing the stick
fo=
rward and then holding in the low tow position. That's the opposite
maneuv=
er of what's leading to kiting. Drifting upwards takes you into the prop
w=
ash and again, it takes forward stick pressure to move into the safe
spot.
=
That feedback mechanism is correctly maintaining the intended safe spot
wh=
ile in the normal tow position only visual cues are being used.
I think I'll give the low tow a try, if ever that polar vortex over
Chicago=
makes like tree...
Herb


I've been aware of the Australian preference for low tow and the reasons
for it for over 30 years. My own flight testing and experience lead me to
believe that it does not significantly reduce the probability of a kiting
accident.

Huh! Sounds good to me!


"GC" wrote in message
eb.com...
On 22/02/2014 16:17, Alan wrote:

...You don't get kiting if you fly normal "high" tow behind the towplane,
if you remain in control.

If you don't remain in control, starting from low tow is not going to
make a lot of difference.

Experience (tens of thousands of aerotows) shows there is an enormous
difference. The inadequate control and time to go from high tow to kiting
is orders of magnitude different from that required to go from low tow to
kiting. In fact, I've never heard of that ever happening. Even with low
time students. Kiting from high tow, however, is apparently so common as
to need a whole new system of electronic whizzbangery and gallons of
bandwidth to stop.

If the tug has just lifted off, being in low tow sounds a bit
difficult,
but that would be a particularly hazardous time.

Yes. Liftoff is a time to be wary and we train accordingly. Nevertheless,
all I can say is that low tow has prevented kiting accidents for many
years. But don't take my word for it, keep this ridiculous discussion
going with another screwball idea for pivoting, autoswivelling,
pitch-sensing, stick-following nonsense.

If the issue is serious - as it was in Australia - flying low tow will
solve it. If it isn't - see my previous post.

GC



As for automatic methods to mitigate the problem, perhaps the solution
is not to modify tow planes, but to modify gliders. If the glider is
in a very high pitch attitude on tow, it might be a good time to
automatically
release.

Another modification might be to attach the tow rope to the top of the
glider.
This would cause the tow force to pitch the glider down.


Is this more of a problem when folks try to tow a slow glider like a
2-33 at
high speeds?

Alan

I hear you on the low tow, GC. It is another of those perceptions of "It isn't what we do, so it must be dangerous." Agree that it will change the dynamics involved, as well. Did Australia go to low tow to prevent kiting, or was it for some other reason and that was a side benefit? I know that high tow increases the trim drag on the towplane, and low tow reduces it, so on low powered towplanes, this can be the difference between climbing and not. With America tending to be a land of excess (horsepower in our towplanes), it is seldom an issue.

So, I am curious. Was the change made to improve climb rates and you just have not seen kiting events in Australia, or was there a significant kiting problem, and low tow was determined to be a solution? No, I am not being snide or snarky, I do not know and would like ot learn.

Eyes and ears open, willing to learn.

Steve Leonard

On Sunday, February 23, 2014 10:00:51 AM UTC-5, Steve Leonard wrote:
I hear you on the low tow, GC. It is another of those perceptions of "It isn't what we do, so it must be dangerous." Agree that it will change the dynamics involved, as well. Did Australia go to low tow to prevent kiting, or was it for some other reason and that was a side benefit? I know that high tow increases the trim drag on the towplane, and low tow reduces it, so on low powered towplanes, this can be the difference between climbing and not. With America tending to be a land of excess (horsepower in our towplanes), it is seldom an issue. So, I am curious. Was the change made to improve climb rates and you just have not seen kiting events in Australia, or was there a significant kiting problem, and low tow was determined to be a solution? No, I am not being snide or snarky, I do not know and would like ot learn. Eyes and ears open, willing to learn. Steve Leonard

I'll speak for one operation in US using low tow.
1- Reduced trim drag- glider is on the thrust line of the tug.
2-Easier to fly and teach due to visual picture being good and getting near the wake gives feel of vertical tail touching the wake allowing minor correction to stay away. In high tow the fuselage and wing get in first acusing a bit more disturbance to the glider attitude.
3- Many students fly the tow without help on their first try. I doubt that happens much in high (normal) tow.
4- Almost never get slack rope because descending position is easily seen. We have to go out of our way to teach slack rope correction.
5- No broken ropes.
6- No affect on attitude of tug due to rope reduces tug pilot workload.
7- Glider is not in the wake on takeoff because ground effect dissipates the wake below about 1 wing span.
8- I have not heard of any dead tug pilots in low tow.

Flame suit on
UH

I'm confused by a couple of statements in this thread...

1) "Low tow prevents kiting"
Doesn't the kiting event often happen in early take-off,
just as glider is leaving the ground, and before low-tow
is established???

2) "Nose hook prevents kiting"
Didn't we have at least one fatal accident in USA
with a nosehook (L-13 IIRCC)??? Others???
Anybody have any facts (Yes, I know, its RAS, but...)???
I'm not saying nose-hooks don't help, however...

But then, I'm easily confused...
Thanks,
Best Regards, Dave

On 2/23/2014 10:23 AM, Dave Nadler wrote:
I'm confused by a couple of statements in this thread...

1) "Low tow prevents kiting"
Doesn't the kiting event often happen in early take-off,
just as glider is leaving the ground, and before low-tow
is established???

2) "Nose hook prevents kiting"
Didn't we have at least one fatal accident in USA
with a nosehook (L-13 IIRCC)??? Others???
Anybody have any facts (Yes, I know, its RAS, but...)???
I'm not saying nose-hooks don't help, however...

But then, I'm easily confused...
Thanks,
Best Regards, Dave


To me, "kiting" is a dynamic event initiated by a pull on the "kite line",
geometrical effects then combining to result in the glider ascending up the
arc of the line despite Joe Pilot's subsequent full-forward stick inputs. How
the glider gets into the position where it can kite might be (say) on a winch
launch (think CG-hook-equipped Ka-6, K-8, Nimbus II [Dick Johnson]), or (say)
on an aerotow where Joe Pilot (for some reason) puts in a quick, ill-advised
aft stick, thus presenting the belly of the CG-hook-equipped glider to the
free stream airflow.

By this definition, "kiting" is distinct from Joe Pilot simply getting out of
position above the towplane for any other reason (say, inattention).

I've the same question as you regarding 1) above...

As for 2) I'm satisfied an incompetent or inattentive Joe Pilot can yank a tug
into a dive regardless of the type of hook the glider has. Which conclusion is
100% independent (IMO) of the "kiting" issue.

Bob W.