Anything I can assist with just ask. HpH aircraft are beautifully finished and 
a delight to fly. 

> On 14 Jul 2014, at 2:20 pm, John Roake <[email protected]> wrote:
> 
> On 14/07/14 2:55 PM, "Rob Izatt" <[email protected]> wrote: Our
> reply  hereunder:
> 
> We must be on the ball!
> 
> Only last week, I approved the costs of Aldo Cernezzi's travel to the
> TwinShark factory for a write up on the plant and their M.D.'s stated goals
> for this new two seater. Comments filtering through seem they have goals and
> hopes 'over the moon'.
> 
> Hope to have it all on hand to appear in  the space reserved in our next
> issue.
> 
> John Roake
> 
> 
>> HpH have been spending considerable time and money on this point with
>> engineers who specifically work in the wide body jet area. The TwinShark has
>> been delayed as the boss is adamant he wants something better. One of the
>> primary areas they are also working on is the weight of non flying parts -
>> fuselage. The factory does risk missing the boat with the Arcus/32/JS2 unless
>> of course it is great.
>> 
>>> On 14 Jul 2014, at 12:39 pm, Richard Frawley <[email protected]> wrote:
>>> 
>>> what is presented here seems to be in contradiction to the successes and
>>> efficiency of wide body jets vs their narrow body predecessors.
>>> 
>>> I would be very interested to hear from design experts in this thread. From
>>> what i have read from experts elsewhere, it appears to be not the cross
>>> sectional area of the fuze that makes the difference, but the actual overall
>>> design (to maintain laminar flow and minimize separation)  and particularly
>>> the efficiency of the interface between fuze and the wing that can have
>>> significant effect.
>>> 
>>> 
>>> 
>>> 
>>> 
>>> At 10:30 PM 13/07/2014, you wrote:
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>>>> 
>>>> 
>>>> Today's Topics:
>>>> 
>>>>  1. Re: 20M gliders (Matthew Scutter)
>>>>  2. Re: 20M gliders (Mike Borgelt)
>>>> 
>>>> 
>>>> ----------------------------------------------------------------------
>>>> 
>>>> Message: 1
>>>> Date: Sun, 13 Jul 2014 16:18:50 +1000
>>>> From: Matthew Scutter <[email protected]>
>>>> Subject: Re: [Aus-soaring] 20M gliders
>>>> To: "Discussion of issues relating to Soaring in Australia."
>>>>       <[email protected]>
>>>> Message-ID:
>>>>       <CALubygTZ5j=A3Mj-4eiXPJAZTcxKN0uBQ=co_x5eb_lxfke...@mail.gmail.com>
>>>> Content-Type: text/plain; charset="utf-8"
>>>> 
>>>> I see EB has essentially fit two pilots in a single seat EB29 with their
>>>> EB29D (
>>>> http://www.binder-flugmotorenbau.de/eb29d-racing-doppelsitzer.html?&L=1),
>>>> so I expect there is plenty of scope for improvement in fuselage size with
>>>> ergonomic innovations.
>>>>> On 12 Jul 2014 22:34, "Harry" <[email protected]> wrote:
>>>>> 
>>>>>  Mike,
>>>>> 
>>>>> It?s all about driving a large fuselage through the air. The quite small
>>>>> size difference between say, a Discus A and B fuselage makes an 
>>>>> appreciable
>>>>> difference in performance, particularly at higher speeds. Compare the
>>>>> massive size difference between an ASG 29 and a two seater fuselage. I
>>>>> don?t know what the actual drag figures are but they must be a large
>>>>> difference. Likewise the two seater ASH 25 and Nimbus 3DMs and 4DMs are
>>>>> left far behind the ballasted 18 metre gliders when the speeds get up a
>>>>> bit. The actual Arcus fuselage is very similar to the 20 year old Nimbus 
>>>>> 3D
>>>>> fuselages so I guess there was not much scope to improve them much.The
>>>>> Jonkers JS fuselage is reputed to be an exact copy of an earlier German
>>>>> glider. Actually expected the new Schleicher 32 fuselage, being a new
>>>>> design, to have lesser drag but the information from Finland is not
>>>>> indicative of a substantial improvement. Time will tell. Am sure you could
>>>>> give us some useful information on drag calculations,
>>>>> 
>>>>> Harry Medlicott
>>>>>  *From:* Rob Izatt <[email protected]>
>>>>> *Sent:* Saturday, July 12, 2014 7:09 PM
>>>>> *To:* Discussion of issues relating to Soaring in Australia.
>>>>> <[email protected]>
>>>>> *Subject:* Re: [Aus-soaring] 20M gliders
>>>>> 
>>>>> You can get two people in a two seater and share the fun which is the
>>>>> wholepoint of said two seaters. Without handicaps glider comps would be
>>>>> even less viable.
>>>>> 
>>>>> On 12 Jul 2014, at 5:59 pm, Mike Borgelt <[email protected]>
>>>>> wrote:
>>>>> 
>>>>> From what has been written here over the last few days, it is
>>>>> disappointing that a new flapped 20M two seater doesn't have as good
>>>>> performance as a 15M unflapped glider.
>>>>> 
>>>>> Mike
>>>>> 
>>>>> 
>>>>> *Borgelt Instruments* -
>>>>> *design & manufacture of quality soaring instrumentation since 1978*
>>>>> www.borgeltinstruments.com
>>>>> tel:   07 4635 5784     overseas: int+61-7-4635 5784
>>>>> mob: 042835 5784                 :  int+61-42835 5784
>>>>> P O Box 4607, Toowoomba East, QLD 4350, Australia
>>>>> 
>>>>> _______________________________________________
>>>>> Aus-soaring mailing list
>>>>> [email protected]
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>>>>> 
>>>>> ------------------------------
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>>>>> 
>>>>> 
>>>>> _______________________________________________
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>>>> -------------- next part --------------
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>>>> 
>>>> ------------------------------
>>>> 
>>>> Message: 2
>>>> Date: Mon, 14 Jul 2014 12:00:07 +1000
>>>> From: Mike Borgelt <[email protected]>
>>>> Subject: Re: [Aus-soaring] 20M gliders
>>>> To: "Discussion of issues relating to Soaring in Australia."
>>>>       <[email protected]>
>>>> Message-ID: <[email protected]>
>>>> Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
>>>> 
>>>> Rob,
>>>> I've done enough 2 seat cross country flying to
>>>> realise the fun involved, I'm talking aerodynamics.
>>>> 
>>>> Harry,
>>>> 
>>>> There may be more wetted area and cross section
>>>> on the 2 seat fuselage but comparing a Discus2 B
>>>> to an Arcus  (this necessarily approximate) I get
>>>> about 32% more cross section on the Arcus
>>>> fuselage and about 49% more wetted area. Shape is
>>>> similar so I'd expect similar drag coefficients.
>>>> The mass is 800 Kg vs 525 at gross which is 52%
>>>> greater so at any given sink rate the POWER is
>>>> 52% greater. The wing area is 15.6 M^2 vs 10.16
>>>> M^2 so a ratio of 1.54 (rounded up).
>>>> No large differences (slightly worse at 750Kg)
>>>> and as the Arcus has flaps I'd expect it to
>>>> perform the same at mid range speeds and better
>>>> at high speeds where the Standard Class glider
>>>> starts to go out of the low drag region of the airfoil.
>>>> Span loading is different though (mass per unit
>>>> span) for the Arcus 800/20 =40, for the D2 525/15
>>>> 35. Induced drag is dependent on the square of
>>>> the span loading - derived here
>>>> http://aerocrafty.blogspot.com.au/2013/06/span-loading.html
>>>> (weird website behaviour on my office PC but
>>>> works Ok in the iPad in Chrome) so yes, the two
>>>> seat Arcus and ASG32Mi likely will climb worse
>>>> than the 15M standard class glider even though
>>>> the Reynolds numbers on the Arcus wing are 15%
>>>> higher (lower profile drag coefficient). Why the
>>>> high speed performance is worse is a mystery.
>>>> 
>>>> I don't have any numbers on the height and width
>>>> of the ASG32 fuselage but if less than that of
>>>> the Arcus I'd expect an improvement.
>>>> 
>>>> I wouldn't draw any conclusion about the ASG32
>>>> performance from Finland except that it is
>>>> clearly not a terrible glider in performance
>>>> compared to the Arcus and looks nice.
>>>> 
>>>> Mike
>>>> 
>>>> 
>>>> 
>>>> 
>>>> At 10:33 PM 12/07/2014, you wrote:
>>>>> Mike,
>>>>> 
>>>>> It???s all about driving a large fuselage
>>>>> through the air. The quite small size difference
>>>>> between say, a Discus A and B fuselage makes an
>>>>> appreciable difference in performance,
>>>>> particularly at higher speeds. Compare the
>>>>> massive size difference between an ASG 29 and a
>>>>> two seater fuselage. I don???t know what the
>>>>> actual drag figures are but they must be a large
>>>>> difference. Likewise the two seater ASH 25 and
>>>>> Nimbus 3DMs and 4DMs are left far behind the
>>>>> ballasted 18 metre gliders when the speeds get
>>>>> up a bit. The actual Arcus fuselage is very
>>>>> similar to the 20 year old Nimbus 3D fuselages
>>>>> so I guess there was not much scope to improve
>>>>> them much.The Jonkers JS fuselage is reputed to
>>>>> be an exact copy of an earlier German glider.
>>>>> Actually expected the new Schleicher 32
>>>>> fuselage, being a new design, to have lesser
>>>>> drag but the information from Finland is not
>>>>> indicative of a substantial improvement. Time
>>>>> will tell. Am sure you could give us some useful
>>>>> information on drag calculations,
>>>>> 
>>>>> Harry Medlicott
>>>>> From: <mailto:[email protected]>Rob Izatt
>>>>> Sent: Saturday, July 12, 2014 7:09 PM
>>>>> To:
>>>>> <mailto:[email protected]>Discussion
>>>>> of issues relating to Soaring in Australia.
>>>>> Subject: Re: [Aus-soaring] 20M gliders
>>>>> 
>>>>> You can get two people in a two seater and share
>>>>> the fun which is the wholepoint of said two
>>>>> seaters. Without handicaps glider comps would be even less viable.
>>>>> 
>>>>> On 12 Jul 2014, at 5:59 pm, Mike Borgelt
>>>>> <<mailto:[email protected]>[email protected]>
>>>>> wrote:
>>>>> 
>>>>>> From what has been written here over the last
>>>>>> few days, it is disappointing that a new
>>>>>> flapped 20M two seater doesn't have as good
>>>>>> performance as a 15M unflapped glider.
>>>>>> 
>>>>>> Mike
>>>>>> 
>>>>>> 
>>>>>> Borgelt Instruments - design & manufacture of
>>>>>> quality soaring instrumentation since 1978
>>>>>> www.borgeltinstruments.com
>>>>>> tel:   07 4635 5784     overseas: int+61-7-4635 5784
>>>>>> mob: 042835 5784                :  int+61-42835 5784
>>>>>> P O Box 4607, Toowoomba East, QLD 4350, Australia
>>>>>> _______________________________________________
>>>>>> Aus-soaring mailing list
>>>>>> <mailto:[email protected]>[email protected]
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>>>>>> /lists.internode.on.net/mailman/listinfo/aus-soaring
>>>>> 
>>>>> 
>>>>> ----------
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>>>> 
>>>> Borgelt Instruments - design & manufacture of
>>>> quality soaring instrumentation since 1978
>>>> www.borgeltinstruments.com
>>>> tel:   07 4635 5784     overseas: int+61-7-4635 5784
>>>> mob: 042835 5784                :  int+61-42835 5784
>>>> P O Box 4607, Toowoomba East, QLD 4350, Australia
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>>>> End of Aus-soaring Digest, Vol 130, Issue 19
>>>> ********************************************
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