Thanks Gary,
All pretty good now - although not as comfy as my 29. [the sleekest fuselage 
but the most room! - for width, not length]
Crashability is another consideration with cockpits.
After seeing Mak's landing with his Diana2 I think that and low speed ground 
stability needs work! :]  [Mak and glider both intact but it was speccy!]

Off to water up for day 2!
Tom



________________________________
From: "[email protected]" <[email protected]>
To: Discussion of issues relating to Soaring in Australia. 
<[email protected]>
Sent: Sunday, 7 August 2011 4:16 PM
Subject: Re: [Aus-soaring] 'A' model glider fuselages

Hi Mart,
First let me say that Tim Shirley's response to your email should give you
about 99% of the background, and as Tim says "size does matter", for reasons 
that I discuss below. I do not know for how long you have been gliding, but I 
have been "doing it" for a while! Most of what follows does not bear directly 
on your question,
but you may find it  useful  information in coming to grips with, and 
understanding the "bigger picture".
What you must firstly understand is that nearly all development today is driven 
by what is happening on the competition front. One notable exception is the 
Perlan Project.
I posit the following 3 subjects are where most of the advances have been made:
1. Our understanding of the aerodynamics within the "usual" gliding envelope
in which gliders operate, has increased immensely. Research on the
aerodynamics of a wing section (as always, carried out by dedicated
enthusiasts), has led to a huge performance increase, in a relatively short
period of time.
A state of the art glider design of "today " is certainly of substantially
better aerodynamic design than one that is say 15 years old. It is highly
likely that it better than one that was designed 5 years ago.

                                       ******************
Here I am talking about the design only - as opposed to design and production. 
Some
designs may be absolutely revolutionary, but for one reason or another the
glider itself may never gets into real serial production - think Diana 1, (5 or 
6 produced), and
maybe (more so) Diana 2.
If I heard Todd Clark (the Australian Agent for the
JS1), rightly, last year at Dalby  he said that the estimated manhours to get 
the JS1 Revelation
into production was 75,000 hours! {Todd please confirm!} All these, and the 
actual set up and production costs have to be met before a single glider rolls 
off the line!
So we have a design phase, and a production phase. If the actual elapsed time 
(as opposed
to manhours), from design to production can be minimized, then the company
doing this best will have an advantage over its competitors.
                                        ********************
2. There has been a significant advance (over a relatively short period of
time), in the development of instrumentation that  allows the pilot to know (in 
real time), what is happening in the airmass he is flying in, and what to
do about it. Someone like Mike Borgelt might like to make comment here, and 
gaze into the crystal ball!

3. Finally we come to the glider itself. I will not discuss here the advances 
in material technology that have contributed to make the modern glider what it 
is today, other than to mention an intriguing solution by our pioneers on how 
to cut down the drag produced by an open cockpit. This solution involved the 
fabrication of a laminated WOODEN canopy. The canopy was quite streamlined, but 
as you can imagine it had one drawback. Yes you guessed: It was impossible to 
see either in or out! The solution to this was to cut small portholes in 
"strategic" locations!
The point I want to make here, is that it is only in relatively recent times 
that the sailplane designers have begun to give really serious consideration to 
fact that their splendid machines have to carry  flesh and blood creatures - 
the pilots. So this is the 3rd area of major advance. Pilots can now fly their 
(relatively highly crashworthy), ships in comfort for 5, 10, 15 and more hours 
at a time.

Pilots come in all shapes and sizes. As Tim has pointed out he fits very 
comfortably in an "A" sized fuselage. I, on the other hand do not. Like Tim, I 
too own a Discus. My Discus however has the "B" fuselage. Do I feel 
disadvantaged? Not in the slightest. I can assure you that being physically 
comfortable is of extreme importance, especially when flying in a demanding 
situation. If you are not comfortable you will be distracted by this lack of 
comfort. If you are distracted, even slightly, your decision making is 
adversely affected, and it is the decisions made by the pilot (at maybe one per 
second in a stressful situation), that determines the final outcome of an 
event, MUCH more so than a fraction (or more), of a L/D point. As Ingo Renner 
has said in the past, "the person who makes the fewest errors wins".

If you have been following the OZ team blog from Uvalde, you may now understand 
what Tom Claffey is on about, when he mentions his bad back, and the search for 
the right seating position. Tom, I hope you now have this sorted out. Good luck 
to you and the rest of the team.

Gary

----- Original Message ----- From: "Mart Bosman" <[email protected]>
To: <[email protected]>
Sent: Saturday, August 06, 2011 5:30 PM
Subject: [Aus-soaring] 'A' model gliders


> Hi all,
> 
> I have a question that might have been asked before but I haven't found
> it.
> 
> How come that there are no minimum cockpit sizes for gliders?
> 
> I am following the euros and again the gliders with a small cockpit  that
> apparently have about half a point better glide are leading. For
> yesterday the first 8 are an 'a' model. (or standard small)
> 
> To me it looks unfair that your statue gives you a competition advantage.
> 
> Thanks,
> 
> Mart.
> 
> http://egc2011.pociunai.lt/index.php?option=com_wrapper&Itemid=132
> _______________________________________________
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