HDTenEightyP/NetNews huggingface dataset:
From: rmiller@i88.isc.com (Richard J. Miller)
Subject: Re: waxing
Organization: INTERACTIVE Systems Corporation, Naperville, IL
Date: Fri, 16 Oct 1992 22:33:01 GMT

In article <1992Oct15.145015.9350@abo.fi> HAHLLUND@finabo.abo.fi (Hans Ahllund Inf) writes:
>I have experienced that a well waxed wing is better in glide performace, 
>especially at high speeds. But if it rains , the waxed wing works dreadfully.
>Many PIK-20 owners just sanded their wings with 800 wet sand paper, that
>improved performace dramatically in rain, but this kind of wing
>had to be handled with silk glowes.

only silk gloves?

if you ever tried to touch A.J. Smith's wings on a contest flight line,
he might have tried to kill you no matter what you were wearing (and i
say that only partially in jest). the serious US (and probably German
and a few other) contest types get paranoid about almost anything
(including fingerprints!) before a contest flight and about bugs (a
more reasonable worry) during a flight.

something to be careful about is that sailplane aerodynamics has become
so advanced that it has gotten into the second and third order effects
that no one has ever studied before. laminar flow separation (the
laminar bubble that gets mentionned once in technical articles and then
is shunned for the rest of the article as being too complex) is a
second order effect that is now better understood, but is still not
being controlled in a PRACTICAL way (turbulator calibration hasn't been
discussed anyplace that i have seen yet anyway).

how DOES anyone (including the factory) determine where to put the tape
or the air outlets? especially for a standard class (non-flapped) ship?

Rich Miller
ex-Schempp-Hirth Discus JBX and
ex-Rolladen-Schneider LS-4 TQ
rmiller@i88.isc.com
Newsgroups: rec.aviation.soaring
From: teet@jag.b17a.ingr.com (Teet Jagomagi)
Subject: Are there gliders around Huntsville, AL?
Organization: Mapping & Energy, Intergraph Corp., Huntsville, AL
Distribution: rec
Date: Thu, 15 Oct 1992 15:05:31 GMT

I started gliding 2 years ago in Estonia. I will work at Intergraph, and stay 
in Huntsville, AL for a half a year. Are there gliders not too far from 
Huntsville and enough brave instructors to let me compare estonian and 
american air?

Mr. Teet Jagomagi
teet@jag.b17a.ingr.com
Ph: (205) 730-1844
From: westreic@skye.oc.nps.navy.mil (Eric Westreich)
Newsgroups: rec.aviation.soaring
Subject: SPANISH SOARING
Date: 15 Oct 92 06:49:27 GMT
Organization: Naval Postgraduate School,Monterey CA

I will be moving to ROTA, Spain for three years starting in January.

I would greatfully accept any information on soaring in Spain.

-Eric
 westreic@oc.nps.navy.mil
Newsgroups: rec.aviation.soaring
From: rmiller@i88.isc.com (Richard J. Miller)
Subject: Re: Glider Waxing
Organization: INTERACTIVE Systems Corporation, Naperville, IL
Distribution: usa
Date: Mon, 12 Oct 1992 14:45:59 GMT

In article <mbtdqey@Unify.Com> raveling@Unify.com (Paul Raveling) writes:
>	Does anyone know of comparative performance tests for
>	different techniques of wing preparation?
>
>	I'm curious because similar questions apply to racing sailboats
>	that are stored out of the water -- i.e., those with gelcoat
>	rather than bottom paint below the waterline.  The majority
>	opinion among those racing such boats was clearly to avoid
>	waxing below the waterline, but to keep the gelcoat in shape
>	by wet sanding with 600-grit paper, then buffing.

i don't have any data, but there is some out there. for the record,
waxing contest sailplanes in the US went out of vogue in the mid-70's
and is only starting to come back now because the current mania seems
to be gelcoat and glass degradation which waxing can reduce.

Mark Maughmer, who did some of the wing design for Cygnet (and is at
Penn State and available on e-mail if he could be coerced to read it,
hint hint to you Happy Valley folk! (tell him i sent you :-))) )), has
told me that it's just not possible to make the wax surface smooth enough,
especially compared to the glass surface. wax doesn't follow the surface
form perfectly, but rather clumps up creating bumps that cause the flow
to detach. but he also said that air flow seems to like a smooth surface
(the glass) that has then been roughened slightly with 400 or finer
sandpaper. that seems to keep the flow attached better, even if it is
slightly turbulent (or because it is!).

Rich Miller
ex-Schempp-Hirth Discus JBX and
ex-Rolladen-Schneider LS-4 TQ
rmiller@i88.isc.com
Newsgroups: rec.aviation.soaring
From: HAHLLUND@finabo.abo.fi (Hans Ahllund Inf)
Subject: re:re:re:scratching
Organization: Abo Akademi University, Finland
Date: Wed, 7 Oct 1992 17:52:14 GMT
X-News-Reader: VMS NEWS 1.23


>I'm a little puzzled by this account because when a blue bubble
>reaches the condensation level, it is not at the top of its climb.  In
>fact, since the latent heat of vaporization is being released by the
>condensation, the ambient lapse rate only needs to exceed the
>saturated pseudo-adiabatic lapse rate (SALR) rather than the dry
>adiabatic lapse rate (DALR) to continue the climb.  Since the SALR
>(5C/km) is less than the DALR (10C/km) the "bubble" would actually
>tend to accelerate after it reaches the condensation level.


I don't know what your getting at here but , when a bubble starts to
be condensed into a cloud , it is NOT a bubble anymore.
Every cloud originated from a bubble, but after they become clouds 
the shape and carachteristics of the lift becomes completely different...
Newsgroups: rec.aviation.soaring
From: bruceb@ctpm.uq.oz.au (Bruce Blackshaw)
Subject: Re: Hunting for thermals.
Organization: Centre for Language Teaching and Research, Uni of Queensland, AUSTRALIA.
Date:  8 Oct 92 22:36:58 GMT

deitsch@sol.crd.ge.com (Andy Deitsch) writes:

>> >   I'd like to start a discussion on how people hunt for thermals.

>I fly hang gliders not sailplanes, so I'm not sure if you can use
>this technique due to the fact that you can't look straight down, but
>I look for trees lit up when I'm mountain flying.  In other words the
>backs of the leaves are visible on trees where thermals are currently
>passing through.  This technique works very well!

I too fly hang gliders.  I've almost lost count at the number of low
saves I've made at less than 500' AGL by flying just downwind of a
farmer ploughing his paddock.  Tractors make good thermal triggers its
seems.

--
****************************************************
Bruce Blackshaw bruceb@ctpm.uq.oz.au   
"... I'd rather be hang gliding ..."
****************************************************
Newsgroups: rec.aviation.soaring
From: laforce@xenon.arc.nasa.gov (Soren LaForce)
Subject: Re: Ballasting a glider
News-Software: VAX/VMS VNEWS 1.41    
Organization: NASA Ames Res. Ctr. Mtn Vw CA 94035
Date: Wed, 7 Oct 1992 15:38:00 GMT

In article <9210062132.AA12271@lri.uwo.ca>, root@lri.uwo.ca (0000) writes...
> 

stuff deleted

> 
> 
>NO!! NO!! NO!!
>Sorry folks, but the polar does change as a function of wing loading.
>If you look at the polars for the new breed of gliders it is *very* obvious
>that it changes. Additionally, if you look at some glider adverts, 
>the best glide ratio improves with greater wing loading.
> 
>Unfortunately, I am not too terribly clear on why the glide ratio changes.
>Since the new gliders can change the wing loading thru a tremendous range
>the Re numbers will change significantly. Perhaps this is one of the 
>reasons.
> 
>What bothers me, however, is that the formulas in basic aerodynamic
>books clearly shows that wing loading is not a factor. The only way
>I can see the formulas being correct, yet the polars changing with
>wing loading is if the wing characteristic changes significantly with
>Re, hence some of the terms in the equations a functions, not 
>constants.

Your conclusion is probably correct.  **All** equations are 
approximations.  Some are better than others.  What you read in
any basic book is just that, basics.  Fluid dynamics is not a 
simple, easily described subject.  The governing differential
equations are non-linear and have never been solved for the 
general case, thus any formulae you see are either empircally
determined or applicable to specific (usually 2 dimensional) 
cases.



--Soren            laforce@xenon.arc.nasa.gov
From: bedford@hobbes.ucsd.edu (Don Bedford)
Newsgroups: rec.aviation.soaring
Subject: RE: waxing
Date: 12 Oct 92 22:48:06 GMT
Organization: SAIC, San Diego


Howdy- As I am new to this news group and very new to this sport I can't
add too much about wing waxing but I have been racing sail boats for 20
years and have been sanding my hulls for just as long.

True, that waxing is slow on a sailboat.  Racers wet sand with 600+ sand
paper to reduce friction and still induce laminar flow.  Keeping a thin
layer of water "sticking" to the hull induces the least amount of friction
on a hull moving through water.  A waxed hull does not have this thin layer
attached to the hull.  I assume that this is also true for air moving over
a wing but as the speed of a plane if faster and the medium is thinner (air)
I wonder what the ideal smoothness of a wing would be (?)

By the way, can anyone hook me up with some good reading ( mag. or book) on
soaring?  I am not interested in racing but I would like to start to
get my pilots licence.  (told you I was new...)

Thanks for your help

Don Bedford
Newsgroups: rec.aviation.soaring
From: Michael Steckner <steckner@lri.uwo.ca>
Subject: Ballast can improve LD reply
Organization: Relayed-by-Sendmail
Date: Thu, 15 Oct 1992 02:27:27 GMT
To: rec.aviation.soaring@julian.uwo.ca

About a week ago I contradicted someone who stated that LD does not change
with wing loading. I stated that if you look at some of the polars of modern
gliders you can see that they change. Well, I cannot find the stupid polars I
am looking for! BUT I have a reference which specifically addresses this issue,
and the added bonus is that it tries to explain why LD can change with wing
loading.

Piggott
Understanding gliding
2nd ed paperback 1987
pg 109 - 110

I quote (without permission, of course)

One surprising bonus can come from carrying extra weight, as we have seen. Far from spoiling the gliding angle, it may, in fact, improve it. The rather small
chord of the wingtips on some machines is actually more efficinet at the slightly
higher spees needed with extra weight. For example, the theoreitical performance
curves for the Kestrel show an improvement in the best gliding angle from 43:1 at
48 knots when it is flown at an all up weight of 880lb to over 44:1 at 53 kn with an extra 160 lb carried. 

So there we are.

I have seen some adverts where they specify two best LD at two extreme wing
loading values. I thought the discus curves was one (Hmmm, talk about narrow
tips ...) the other being either the ASW27 vapourware or the LS7.

Hope this is a reasonable answe
Newsgroups: rec.aviation.soaring,rec.aviation.homebuilt
From: andrew@RedBrick.COM (Andrew Weiss)
Subject: human powered/human assisted flight
Organization: Red Brick Systems, Los Gatos, CA
Distribution: usa
Date: Tue, 13 Oct 1992 21:21:42 GMT

   Does anyone have information concerning human powered/human assisted, self-launched
gliders?

   Thanks.
From: myoung@joker.asd.sgi.com (mark young)
Newsgroups: rec.aviation.soaring
Subject: Re: Are there gliders around Huntsville, AL?
Date: 15 Oct 1992 16:06:36 GMT
Organization: Silicon Graphics, Inc.  Mountain View, CA
Distribution: rec
NNTP-Posting-Host: joker.asd.sgi.com

In <TEET.92Oct15100531@jag.b17a.ingr.com> teet@jag.b17a.ingr.com (Teet Jagomagi) writes:

>I started gliding 2 years ago in Estonia. I will work at Intergraph, and stay 
>in Huntsville, AL for a half a year. Are there gliders not too far from 
>Huntsville and enough brave instructors to let me compare estonian and 
>american air?

There is an airport north and east of town called moontown.  When I worked
for intergraph, I went out there a couple of times.  One day they actually
had a glider club open house.  Don't know how the conditions are for soaring
though...never became a glider pilot.

btw, one of the astronauts from the last shuttle mission (name escapes me,
the married female) learned to fly GA at moontown.

...myoung

From: rjc@hpfcso.FC.HP.COM (Rich Carr)
Date: Sat, 10 Oct 1992 14:08:24 GMT
Subject: Re: Ballasting a glider
Organization: Hewlett-Packard, Fort Collins, CO, USA
Newsgroups: rec.aviation.soaring

> NO!! NO!! NO!!
> Sorry folks, but the polar does change as a function of wing loading.
> If you look at the polars for the new breed of gliders it is *very* obvious
> that it changes. Additionally, if you look at some glider adverts, 
> the best glide ratio improves with greater wing loading.
> 
> Unfortunately, I am not too terribly clear on why the glide ratio changes.
> Since the new gliders can change the wing loading thru a tremendous range
> the Re numbers will change significantly. Perhaps this is one of the 
> reasons.
> 
> What bothers me, however, is that the formulas in basic aerodynamic
> books clearly shows that wing loading is not a factor. The only way
> I can see the formulas being correct, yet the polars changing with
> wing loading is if the wing characteristic changes significantly with
> Re, hence some of the terms in the equations a functions, not 
> constants.

As you note, this flies in the face of basic aerodynamic theory.  Can
you provide some pointers to these new polars?

The Reynolds number effects should only amount to a percent or so
difference in glide ratio over the glider's speed range.  This is
pretty small compared to the cruise advantage of higher wing loading.

Rich Carr
Newsgroups: rec.aviation.soaring
From: cohler@vxcrna.cern.ch (Mike Cohler)
Subject: Soaring USA Request
News-Software: VAX/VMS VNEWS 1.41    
Organization: European Organization for Nuclear Research, CERN
Date: Mon, 12 Oct 1992 10:38:00 GMT

I have a request for information on Soaring Clubs in the USA.
Next year my partner and myself are planning a trip to Ontario, and
from there flying in a C182 for 3 weeks around the USA, possibly ending
up in the Lake Tahoe area, and then retutning to Ontario. We will
either be there in the spring or the fall in 1993.  During our trip
we would like to stop off at a gliding/soaring club and do some gliding.
Our route is not yet fixed, and we are still thinking about which route
to take.  However if we had some information about gliding clubs which
might allow us to land a C182 and stop off for a day or so on the way
then we could decide our route to include such a stop.
   Therefore I would greatly value any information on the following
a) A USA gliding club, which would allow a visiting UK pilot with silver "C"
   to fly their aircraft after a site check ride
b) The name of club, name of a contact man/woman, phone number and address.
c) The current cost of launch (aerotow and winch), hire time, instructor time
   and daily membership costs, and whether a foreigner would be allowed
   to fly solo.
d) Likely soaring possibilities eg hills/ridge/wave/thermal in May or Sept.
e) Likely weather in these months.
f) If the club would allow a C182 to tie down overnight, what is the cost ?
g) What aircraft the club has available to fly.
h) Whether the club operates every day or just weekends.
Note I am not interested in passenger rides at high prices as an "experience
flight".

I would appreciate any of the above info by email (preferably to my York
email address below) or by a posting to the net.  Alternatively, if any kind
soul has a small leaflet from their club, and would post it to me at my
work address: ie Dr M.D. Cohler, Department of Physics, University of
York, Heslington, York YO1 5DD, England, then I would be very grateful, 
and will pin the leaflet up on our club wall to offer the facilities
of your club to other members of our club travelling to the USA also.

I have leaflets from Sugarbush Soaring already due to a colleague who came back
from New England last week.

Yours hopefully...
Mike

==============================================================
|                                                            |
|        Mike Cohler -  preferred email address:             |
|                       MDC1@VAXA.YORK.AC.UK                 |
|                   ie  MDC1%VAXA.YORK.AC.UK@UKACRL.BITNET   |
|                                                            |
|        UK PPL and Glider Pilot                             |
|                                                            |
==============================================================
From: rivan@bnr.ca (Robert Ivan)
Newsgroups: rec.aviation.soaring
Subject: gliding in ottawa
Date: 9 Oct 92 18:21:18 GMT
Reply-To: rivan@bnr.ca
Organization: Bell Northern Research Ltd.


 Paul you bounced....


 I am a member of the Rideau Valley Soaring club out at KARS.
Some other people on the net should be from Gatineau.  Anyway this year
was not the Year for Gliding so consider yourself lucky.  On average
i spend between $1200 and $1500 a year and that includes everything.
I dont own a glider but am solo and very close to a
license ( if we had had a good summer).   If you are
interested there is a ground school run by both clubs in FEb
for about 3 months and is $25.  Just contact one of the clubs.

Rob
Newsgroups: rec.aviation.soaring
From: geoff@peck.com (Geoff Peck)
Subject: CHARTER: rec.aviation.soaring
Followup-To: rec.aviation.misc
Reply-To: geoff@peck.com
Organization: Geoffrey G. Peck, Consultant, San Jose CA
Date: Mon, 12 Oct 1992 17:23:37 GMT

Welcome to rec.aviation.soaring.  This message, and companion messages
like it, will be posted to each of the new rec.aviation.* groups weekly
through the end of November, to allow people to view the charters of each
newsgroup and better understand where to post articles.

The charter of rec.aviation.soaring is:

*****************************************************************************
*   Soaring and hang-gliding: equipment, maintenance, instruments, safety,  *
*   training, soaring sites, current events, FAI badge rules and class      *
*   definitions, meteorology, history, homebuilts, vintage sailplanes, the  *
*   science and technology of motorless flight, etc.                        *
*****************************************************************************

There are now a thirteen separate subgroups on rec.aviation; if the charter
above doesn't match the content of the article you're posting (or you're
following up), please consider one of the other groups as a more
appropriate forum:

    announce (MOD)    military      piloting        soaring
    answers  (MOD)    misc          products        stories (MOD)
    homebuilt         owning        simulators      student
    ifr 

A common question is "what should I do if an article spans the charters of
two or more groups?"  The answer is cross-posting.  If you have an article
which clearly crosses the boundaries of several groups, you should post a
**single** copy of the article to **all* of the groups.  Don't post
separate copies to each group.  Most modern newsreaders will display the
article exactly once to the reader -- in the first group in which it is
encountered and read.

If you feel that the replies should be directed to a subset of the groups
to which you are submitting your post, be sure to include a line of the
form "Followup-to: groupname" in the header of your message.  See the
header of this message for an example.

If you are replying to a cross-posted article and your reply is germane to
only a subset of the original groups, please ensure that you check the
Newsgroups: line to remove unnecessary groups.  If the reply is germane to
all the groups in which the article was originally posted, try to ensure
that all the groups are listed in the Newsgroups: line.  Some older
newsreaders cause a reply to go only to the group which is currently being
read.

Use cross-posting sparingly.  If an article "90% belongs" in one group and
"10% belongs" in another, post it only to the first group.

						Geoff

Newsgroups: rec.aviation.soaring
From: gaynier@elec.uq.oz.au (Ron Gaynier)
Subject: Re: Scratching
Organization: Prentice Centre, University of Queensland
Date: Wed, 7 Oct 1992 23:53:47 GMT

In <1992Oct5.155640.22184@astroatc.uucp> ludeman@astroatc.uucp (Weekend Pilot) writes:

"|"In article <gaynier.718246437@s1.elec.uq.oz.au> gaynier@elec.uq.oz.au (Ron Gaynier) writes:
"|">
"|">I have often heard people talk about climbing to the top of a rising bubble
"|">of air, I don't think this is possible. Remember that a glider is normally 
"|">sinking through the air mass even when thermaling. 

"|"Clarence See, in the course of forty or more years of flying sailplanes,
"|"told me that exactly *twice* he has thermaled up in the blue to  the 
"|"condensation level and had a cumulus start to form all around him -- i.e.
"|"he was indeed at the very top of the bubble.  This is possible if the thermal
"|"follows the torroidal bubble model, the sailplane is well centered in the
"|"core and the core rate of rise exceeds the overall rate of rise by more
"|"than the sink rate of the sailplane.  Pretty neat.  
"|"-- 
"|"Evan Ludeman   
"|"astroatc!ludeman@spool.cs.wisc.edu 

OK, OK! I believe, I BELIEVE!! :-) :-) :-)

Ron Gaynier
From: deitsch@sol.crd.ge.com (Andy Deitsch)
Newsgroups: rec.aviation.soaring
Subject: Re: Hunting for thermals.
Date: 7 Oct 92 20:41:13 GMT
Reply-To: deitsch@sol.crd.ge.com
Organization: GE Research & Development

> >   I'd like to start a discussion on how people hunt for thermals.

I fly hang gliders not sailplanes, so I'm not sure if you can use
this technique due to the fact that you can't look straight down, but
I look for trees lit up when I'm mountain flying.  In other words the
backs of the leaves are visible on trees where thermals are currently
passing through.  This technique works very well!

-- 
_________________________________________________________________________
Andy Deitsch                             email    : deitsch@crd.ge.com  
GE Corporate Research & Development      phone    : (518) 387-7207   
Schenectday, NY 12301                    dial comm: 833-7207     
Newsgroups: rec.aviation.soaring
From: gaynier@elec.uq.oz.au (Ron Gaynier)
Subject: Competitions
Keywords: First time competitor
Organization: Prentice Centre, University of Queensland
Date: Thu, 8 Oct 1992 01:54:33 GMT

The Queensland State Gliding Championships were held at my gliding
club recently. I competed for the first time and learned ALOT, not
just about competing but about gliding in general.

I was wondering if other people would like to share their experiences
with competing for the first (second, third...) time and what they 
learned.

For instance. The practice day had a rather short task set (250k?),
I flew for over 5 1/2 hours and couldn't make it all the way round!
I cut the corner just to get home. Later in the week I flew two
days of over 300k in about 4 hours. The lesson I learned, from the
very helpful experienced pilots, was that I was flying in too narrow
an altitude band and working too many weak thermals. Secondly I was
starting too early, I wasn't giving anyone else a chance to mark
any thermals for me (please, no comments about leaching :-).

Anyone else want to share lessons learned?

Ron Gaynier

Newsgroups: rec.aviation.soaring
From: derek@watson.ibm.com (Derek Lieber)
Subject: learning to fly (Westchester New York area)
Date: Tue, 13 Oct 1992 18:41:51 GMT
Distribution: usa
Reply-To: derek@watson.ibm.com (Derek Lieber)
Disclaimer: This posting represents the poster's views, not necessarily those of IBM
Organization: IBM T.J. Watson Research Center

A number of years ago I spent some time as a student pilot
(power planes) but never got my license. 
I'd like to return to flying, and would love
to get some experience flying sailplanes. Can anybody
recommend clubs and/or airports in the lower Hudson valley
(or eastern NJ / western Connecticut) offering sailplane rides and/or
instruction? Thanks.

-- 
Derek Lieber
derek@watson.ibm.com
Newsgroups: rec.aviation.soaring