David Glover was there in Guatemala to lobby for his meet.
The CIVL delegates at the Plenary in Guatemala voted 14 to 13 for
the Big Spring location over the Slovakia location for the next flex wing
Worlds. The Rigid Wing Worlds will be held in 2006 at Quest Air in Florida (with
the pre-Worlds there this year).
David Glover writes:
Countries that I think voted for the US Bid given below. Most all
of Slovakia's votes come from countries that were in close proximity to
Slovakia. The Slovakian team was very nice and professional. They could not have
been nicer through the whole process, especially Juarj.
OZ, NZ, CAN, DEN, FIN, SWE, NOR, ICE, GUATEMALA, GERMANY, NETHERLANDS, UK, USA
(I HOPE) and one other country.
Big thanks to all the pilots who sent me emails - it made the difference.
My presentation started very badly. The video on DVD would not play after I had
tested 30 minutes earlier - a half dozen delegates came to the rescue, but to no
avail. I was able to show it during a coffee break. All the other bidders had
very impressive, video and power point presentations - mine ended up being me
talking to them the whole time.
The CIVL delegates are a hard working smart bunch. I was very impressed with how
efficient and professional everything was run. It was great being able to put
names to faces.
The first is to add a second barrel release, although the chance of a barrel
release failure is small. I use a 130 lb braided Dacron weaklink.
Another variation is to add a Linknife with an orange pull-handle over the weak
link. The orange handled Linknife hangs above the right hand on the control bar
and can be released quickly.
(editor's note: I put my primary release at my right hand. Like
Gerry I've also used a secondary barrel release. I use thicker spectra. What is
shown here is thin enough that it might tangle when sliding through the ring or
carabineer at the end of the tow rope (although unlikely)
I do not connect the weaklink to the end of the spectra that goes to the barrel
release as pictured above. The pin (as indicated earlier by Bart Doets) in the
barrel cuts through the weaklink. Much better to put the looped end of the
spectra in the barrel.
Connecting the protow to your harness:
The protow is connected to loops near your shoulders on your harness.
A weaklink loop is looped/tied to the loop at one end of the spectra. This
weaklink loop is pushed through the shoulder loop and then the other end of the
spectra is pushed through that weaklink loop and tightened. You end up with a
loop of weaklink looped through the loop on the shoulder and through the loop at
the end of spectra.
The barrel release also has a loop and it is looped through the loop on the
right hand shoulder of your harness.
The free end of the spectra goes through the light metal ring or carabineer at
the end of the tow rope and then into the barrel.
Spinnaker shackles, V-bridles, weaklink strengths as guesses.
Bill Bryden <bbryden>,
co-author of Towing Aloft, writes:
Rohan indicated in Oz Report issues 37 and 41, that the spinnaker
style shackle release must be used with a metal ring to avoid weaklink
entanglement with the leg of the release. This may be acceptable for situations
where the release is connected to the towline directly. However, in the USA,
most of these type releases are used in conjunction with a “V” bridle which
attaches at the keel and to the pilot. One end of this bridle is connected to
the release and it then unthreads from a ring on the towline upon release
actuation. If a small metal ring is connected to the end of this bridle to
interface with the release, then the potential for entanglement of the bridle
with the tow line while unthreading becomes quite high.
In short, using a ring to address the shackle release deficiencies may well
create a higher probability and possibly worse failure mode when used with
unthreading V bridles.
This is not the first time release issues with these shackle style releases have
occurred. There have been some that were very difficult to actuate when under
higher loads. The release in the shown here avoids some of the issues the
spinnaker shackle presents. This was sold in the USA by Lookout Mountain Flight
Park for aerotowing but I don’t know if they still manufacture this release
presently.
Sadly, the whole issue with poor releases is not new. Other fatalities have
occurred as well. In response to those, performance test procedures were
published in Hang Gliding magazine over a decade ago and are listed in the
appendix of the textbook Towing Aloft as well. While those standards may
certainly need modification for some applications, and I don’t suggest they are
near perfect, they were presented to prompt people to adequately consider the
design rigor and testing that is needed during development and manufacture of
these devices. There is little excuse for many of the release failures that seem
to still occur.
On the subject of weaklink strengths, people should note that all
recommendations being tendered by anyone are essentially just guesses. Some may
be more educated than average and some have clearly been less educated.
The right way to determine the weaklink recommendations would be to measure the
tow line tensions for dozens of flights and pilots and perform a statistical
analysis of them. I performed a good number of surface tows with a tension gauge
at the glider to assess tow line tension. Unfortunately, I only performed a
couple aerotows with the tension gauge in the system to determine if my tension
hypotheses were in the ballpark before Dennis Pagen and I did the towing book.
I watched the gauge and didn't log the tensions with a data recorder. I don't
know if actual tensions at the glider have ever been measured by anyone else. I
hope so but wouldn’t be surprised if it never happened. So, until a good data
analysis occurs, no weaklink strength recommendations are gospel
In the 1980s I had written a successful regatta scoring program,
and traveled a lot, scoring sailboat races. As a result of that, and some
sponsor seed money, in 1986 I started a bid process, that eventually brought the
World Windsurfing Championships to Ft Lauderdale, Florida in 1987, a big budget
event. While I initiated and helped run the event, I was no longer in charge at
all. The sponsor, Plymouth Automobiles, brought in some professional organizers.
Local conditions in Ft. Lauderdale, in December, is often pre or post frontal,
and windy, so we were hopeful, since there was a required wind minimum of 15
knots sustained, to have a valid task. Unfortunately, There was a fairly stable
easterly flow air mass present, from a distant high pressure to the north, for
the duration of the regatta and daily winds topped out at 12 knots sustained.
A couple of us locals, however, knew that this weather regime produced 20-25
knots sustained from sundown 'til about 9 AM the next morning, when it would
inevitably die out. We called it "dawn-patrol weather." We'd get up early and go
sailing before work, to take advantage of the better nighttime wind speed.
Hundreds of competitors from dozens of countries all over the world, encouraged
by this nightly breeze, would be in high spirits, sure that the next day was
going to produce wind for three valid heats. How could the wind die again? But
each morning it, indeed, it did die. They'd look up at the clouds scudding by,
clearly in strong flow, but little on the surface. What the heck?
I beseeched anyone that would listen, that we could get at least one task done,
if only we started at 6 AM, then, if the wind continued into the day, we could
get more done, ( I knew it wouldn't - I had been windsurfing there for 13 years
already) but, at least, the regatta would be valid, with one good task per day.
I was told by the organizers-in-charge, (and racers too), that the previous day
was an anomaly and I was wrong, wind always increases with daytime heating. Net
result, no valid task during the entire ten days and lots of pissed people. My
buddies and I sailed two hours, every morning, in perfect conditions, though.
Shortly after the fiasco, I met a meteorologist/windsurfer from Miami and I
asked why? Seems logical that the daytime heating/sea breeze would kick in,
right?
He said: "because the water in Ft Lauderdale/Miami, is so warmed by the Gulf
stream (it's only 5 miles off the coast there) that, as the nighttime air temps
cooled into the 50s, the water, whose temp was a constant 80F, would warm the
air at the surface, and the lapse rate would increase, and there'd be thermal
mixing between the warmer boundary and the much stronger, cooler 'gradient' wind
(his words) at 1000'. The displaced air would flow to the surface persistently
all night long".
"When the air temperature increased to the mid eighties in the morning, the
temperature at the surface compared to the 'gradient' wind at 1000', would be
equal or less, the thermal activity would cease and surface flow would stabilize
- capped by an inversion at the surface. The natural mechanical turbulence would
then retard the air flow at the surface"
Local knowledge is king. Some people are arrogant. Sea thermals happen. The
descending gust theory further is validated.
(editor's note: Okay, let's see what's going on here. First,
there's no sea breeze because the ocean is quite warm, and warm as or warmer
than the land. Second, this is in December. It is relatively cool on and over the land in
December. There is relatively little sunlight heating up the land, compared with
summer.
Third, the air temperature just above the land during the day is not much if at
all greater than the
air temperature a thousand or so feet up which is being warmed by the generally
easterly flow over the warm water. Therefore an inversion and no thermals over
the ground. With no thermals and therefore no mixing during the day, the boundary layer isn't disturbed. There is no sea breeze (on shore
and easterly
flow in this case) because there are no thermals over the land during the day.
At night, the air is cooled over the land. Perhaps higher above the ocean it is
also cooled as argued above. If so there would be
thermals over the ocean at night and in the early morning due to the fact that
the air near the ocean would be warmer than the air higher up.
But I can't understand why it would cool at night (any more than during the day)
say 1000' up over the ocean. I've asked the meteorologist referred to above and
others. We'll see if there is a better answer for how this phenomena works.
Concerning the use of Aleve may not be in everyone’s best
interest. I was told after having a stroke and receiving a regimen of
examinations, tests and lab work that my stomach showed evidence of years of
Aleve use and that it had added to already noticeable liver damage. Perhaps the
same medical doctor who wrote an essay concerning ibuprofen on your wonderful
report could offer his experienced point of view.
Scott Rutledge triggered by my revival of Peter Gray's thread on
Thermal Nonsense got Peter to respond to a comment on that thread and now it
comes back from the dead
here.
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Sadly, the whole issue with poor releases is not new. Other fatalities have
occurred as well. In response to those, performance test procedures were
published in Hang Gliding magazine over a decade ago and are listed in the
appendix of the textbook Towing Aloft as well. While those standards may
certainly need modification for some applications, and I don’t suggest they are
near perfect, they were presented to prompt people to adequately consider the
design rigor and testing that is needed during development and manufacture of
these devices. There is little excuse for many of the release failures that seem
to still occur.
(NO
CREDIT CARDS)