Antares 18S Maiden Flight

At 17:12 04 June 2006, Eric Greenwell wrote:
While this discussion (which I continue below) is an
interesting one, it
mostly side-steps the RAS response to the announcement
that Lange will
offer an 18 M glider with a gas engine sustainer:

Disappointment.

-To me the disappointing thing is that so much of the
discussion seems to be focused on the motorization
of the self-sustainer version of the Antares 18. There
is a lot more to that aircraft than a way to get home
once you run out of thermals. This aspect seems to
be completely ignored, which is rather strange, since
the goal of gliding is to get somewhere WITHOUT using
the engine.


Nobody seemed excited at the idea that yet another
18 M gas engine
sustainer was going into production, probably because
you can already
get one from Schleicher, Schempp-Hirth, LAK, and DG.
Lange made a
marketing decision, not a technical one, to compete
in this (undoubtedly
larger) market with it's many vendors. They could have
chosen to offer
an 18 M electric sustainer for what I'm sure is a smaller
market, and be
the only vendor, as they did with the Antares.

-As I have tried to explain previously, an electric
self sustainer using currently available (cutting edge)
technology ends up looking very much like the Antares
20E with 18m wingtips. If this is what the market
demands, then why did we have to pull this option from
the market?

The Antares is a very desirable glider, and I would
be very happy with
it. I love the idea, and that is why the Lange 18 M
with a gas engine is
such a disappointment.

-Have you ordered your 20E yet? If the price is the
issue, then:
1: Find out what the real price of the 20E is, the
real bottom line price.
2: Concider that, using current technology, the 18E
price would have to be similar
3: Order a 18S, and wait with installing an engine.






I think this is a very narrow view of what a sustainer
can do and how
they are really used. Don't many European pilots often
take a winch
launch, then use the sustainer to get to lift 20 or
30 miles away?

-And how often do they suffer from engine trouble?

I know some pilots (USA and elsewhere) count on the
sustainer to get them
home in areas where sea breezes and other effects routinely
kill the
soaring near home late in the day. Our club has this
problem, and a
sustainer that provided 3000 feet of climb would be
plenty to overcome it.
Apis and Silent both offer self-launching electrics
with about 1500
meter climb capability. After a typical launch, they
would have even
less climb left than the 1000 meters I suggest would
be adequate for an
electric sustainer. So, there are designers who seem
to think that many
pilots could be happy with much less than 3000 meters
to get home!

-How many Apis and Silent self-launching electrics
do you think have been built? What are their overall
performance.. -As gliders

I am convinced that future technical developments will
allow us to go electrical also for the self sustainer,
but for now the required technology is not available.
Until then, I am afraid we will have to settle on stinky
technology

Andor

Andor Holtsmark wrote:
At 17:12 04 June 2006, Eric Greenwell wrote:
While this discussion (which I continue below) is an
interesting one, it
mostly side-steps the RAS response to the announcement
that Lange will
offer an 18 M glider with a gas engine sustainer:

Disappointment.

-To me the disappointing thing is that so much of the
discussion seems to be focused on the motorization
of the self-sustainer version of the Antares 18. There
is a lot more to that aircraft than a way to get home
once you run out of thermals.

But what does it bring us that was not already available from four other
manufacturers? The 20E brought us something we could not get before, and
that excited us, and we are envious of the pilots that will have them.
I'm sure the 18 meter glider with it's gas sustainer engine will be a
fine glider, but a lot of us were expecting and hoping for something
unique from Lange.

--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"

Andor Holtsmark wrote:
At 17:12 04 June 2006, Eric Greenwell wrote:

I think this is a very narrow view of what a sustainer
can do and how
they are really used. Don't many European pilots often
take a winch
launch, then use the sustainer to get to lift 20 or
30 miles away?


-And how often do they suffer from engine trouble?

Why are these two stroke engines so notoriously unreliable?
When I think about all of the two wheeled vehicles out there that
operate reliably at terrestrial sorts of speeds for years, without the
good flow of cooling air like on an aircraft, I wonder why sustainers
are so problematic. I'm familiar with two strokes being harder to
start, but from discussions here and elsewhere I get the impression they
can be expected to poop out after an hour of use, or less, in the air.
Doesn't seem right. Thoughts? Experience?

Shawn

Andor Holtsmark wrote:
-To me the disappointing thing is that so much of the
discussion seems to be focused on the motorization
of the self-sustainer version of the Antares 18. There
is a lot more to that aircraft than a way to get home
once you run out of thermals. This aspect seems to
be completely ignored, which is rather strange, since
the goal of gliding is to get somewhere WITHOUT using
the engine.

Well, it's a very pretty (and certainly not affordable by me) 18M
glider, but how much is there to discuss given the lack of a measured
polar, and any real performance comparisons with 18M gliders from more
established manufacturers? What makes the 20E interesting to most of us
is its electric motor. The only thing that makes the 18T interesting,
at the moment, is the lack of an electric motor. If it runs away from
the ASG-29s, LS-10, LAK-17As, and V2Cs at the WGC, I'm sure we'll all be
more interested...

Eric Greenwell schrieb:

But what does it bring us that was not already available

What did the ASW28 bring to us that was not already available with the
K8 from the same manufactorer? Just another 15 meter standard glider.
Pretty disappointing.

Stefan

Why are these two stroke engines so notoriously unreliable?

In many cases, I'm sure, it's because they don't run often enough. Two
stroke or four, it's not that they fail, it's that they fail to start.

Tony V.

Tony Verhulst wrote:

Why are these two stroke engines so notoriously unreliable?

In many cases, I'm sure, it's because they don't run often enough.

I think this is especially likely to be true for sustainer engines,
which are only used for a (rare?) self-retrieve, unlike the
self-launchers which are usually run each flight for the launch. That's
why I think many pilots would be interested in the greater reliability
an electric sustainer could provide, even with a reduced range compared
to a gas engine.

--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"

On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
sdotherecurry@bresnannextdotnet wrote:


Why are these two stroke engines so notoriously unreliable?
Thoughts? Experience?

My personal perception of 2strokes as installed on a DG400 and a
DG600M, is of very good to excellent reliability. Never a problem with
the single cylinder 600, a few problems with the 400 (carb needle
valves, HT wires).

aldo cernezzi

2cernauta2 wrote:
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
sdotherecurry@bresnannextdotnet wrote:

Why are these two stroke engines so notoriously unreliable?
Thoughts? Experience?

My personal perception of 2strokes as installed on a DG400 and a
DG600M, is of very good to excellent reliability. Never a problem with
the single cylinder 600, a few problems with the 400 (carb needle
valves, HT wires).

aldo cernezzi

I have no first hand experience, but I was under the impression that the
simplicity of the sustainer engines (no starter, etc) means that they
are quite reliable, if only because there is not much that can break.

On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
sdotherecurry@bresnannextdotnet wrote:

Andor Holtsmark wrote:

Why are these two stroke engines so notoriously unreliable?

I have been flying with sustainer engines (Solo 2350) for more than 10
years in a Discus bT, Ventus2cT and DuoDiscusT and never had a problem
with it.
Most of the times engine problems are the cause of bad maintenance or
incorrect use of the engine.