Discussion:
Antares 18S Maiden Flight
(too old to reply)
d***@nadler.com
2006-05-31 11:39:07 UTC
Permalink
Hi All - I just received the following press release from Lange
Fleugzeugbau:

Maiden flight ANTARES 18S

The first ANTARES 18S made its successful maiden flight Sunday May
28th, 2006. The youngest member of the ANTARES-family of sailplanes
then was put to the acid test during several test flights at the home
airport of Lange Flugzeugbau in Zweibrücken (Germany). In its first
few flights, the sailplane clearly exceeded the development team's
expectations of gentle and nimble handling, and the test pilots decided
to start flutter and spin testing the same day.

The first flights of the ANTARES 18S have also shown that the
aerodynamic design, aiming for outstanding glide performance especially
at middle and high speeds, has yielded the expected results without
compromising on pilots comfort. The remaining flight testing will be
performed rapidly in the next months.

Unlike her larger sister, the self launching electrical glider ANTARES
20E, the ANTARES 18S has been designed as a pure glider for the
18m-class and can be retrofitted or ordered as a self sustainer, the
ANTARES 18T.


This glider is on its way to Sweden to fly in WGC, where everyone hopes
it will stop raining some day...

Best Regards, Dave
Marc Ramsey
2006-06-01 00:55:45 UTC
Permalink
Post by d***@nadler.com
Unlike her larger sister, the self launching electrical glider ANTARES
20E, the ANTARES 18S has been designed as a pure glider for the
18m-class and can be retrofitted or ordered as a self sustainer, the
ANTARES 18T.
Would that be one of those stinky old technology internal combustion
sustainers, or a clean quiet smooth electric sustainer?
d***@nadler.com
2006-06-01 01:03:22 UTC
Permalink
The 18T sustainer would be the sinky kind.
For clean quite smooth electric go for the 20E !
See ya, Dave
Post by Marc Ramsey
Post by d***@nadler.com
Unlike her larger sister, the self launching electrical glider ANTARES
20E, the ANTARES 18S has been designed as a pure glider for the
18m-class and can be retrofitted or ordered as a self sustainer, the
ANTARES 18T.
Would that be one of those stinky old technology internal combustion
sustainers, or a clean quiet smooth electric sustainer?
Eric Greenwell
2006-06-01 02:47:55 UTC
Permalink
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
For clean quite smooth electric go for the 20E !
See ya, Dave
Post by Marc Ramsey
Post by d***@nadler.com
Unlike her larger sister, the self launching electrical glider ANTARES
20E, the ANTARES 18S has been designed as a pure glider for the
18m-class and can be retrofitted or ordered as a self sustainer, the
ANTARES 18T.
Would that be one of those stinky old technology internal combustion
sustainers, or a clean quiet smooth electric sustainer?
I think an electric sustainer would be delightful. It'd be heavier than
a two-stroke system, but cleaner, quieter, and more reliable. It could
sit unused for months without affecting it's reliability.

The batteries would be small enough, it might be practical to recharge
in the trailer with, say, a couple 80 watt solar panels (about $1000 worth).
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Shawn
2006-06-01 02:51:27 UTC
Permalink
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
They're all kinda sinky after you extend them.
Note to Self: Buy lotto ticket.
;-)

Shawn
MaD
2006-06-01 06:51:35 UTC
Permalink
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
And the reason for that is given here:
http://www.lange-flugzeugbau.de/english/menu/menu-akt.htm

The engine could be smaller but the battery pack almost the same size
as for the 20E would make it a *very* heavy 18m glider.

Regards
Marcel Duenner
Eric Greenwell
2006-06-01 16:46:05 UTC
Permalink
Post by MaD
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
http://www.lange-flugzeugbau.de/english/menu/menu-akt.htm
The engine could be smaller but the battery pack almost the same size
as for the 20E would make it a *very* heavy 18m glider.
From the Antares site:

"Building a self-sustainer utilizing electrical propulsion is currently
not possible, because in order to achieve the range required for a
self-sustaining glider, the size of the battery-pack would have to be
comparable to the pack installed in the Antares 20E. This is contrary to
the basic idea behind a self sustaining glider, which is to provide a
very economical way of staying aloft."

I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E,
but weren't willing to accept a similar range limitation for a
sustainer. I suggest a sustainer that could climb 3000' on it's battery
would be enough for a majority of pilots, and this would allow a
significantly smaller battery to be used.
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Paul Remde
2006-06-01 20:18:50 UTC
Permalink
Hi Eric,

Good point. I agree. I think they are missing the boat by going to a gas
engine. It is so contrary to the clean, quiet, simple to operate, reliable
system in the Antares 20E.

I wish I could afford one!

Good Soaring,
--
Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com
Post by Eric Greenwell
Post by MaD
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
http://www.lange-flugzeugbau.de/english/menu/menu-akt.htm
The engine could be smaller but the battery pack almost the same size
as for the 20E would make it a *very* heavy 18m glider.
"Building a self-sustainer utilizing electrical propulsion is currently
not possible, because in order to achieve the range required for a
self-sustaining glider, the size of the battery-pack would have to be
comparable to the pack installed in the Antares 20E. This is contrary to
the basic idea behind a self sustaining glider, which is to provide a very
economical way of staying aloft."
I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E, but
weren't willing to accept a similar range limitation for a sustainer. I
suggest a sustainer that could climb 3000' on it's battery would be enough
for a majority of pilots, and this would allow a significantly smaller
battery to be used.
--
Change "netto" to "net" to email me directly
Eric Greenwell - Washington State, USA
www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Stefan
2006-06-01 20:29:31 UTC
Permalink
Post by Paul Remde
I wish I could afford one!
See? They probably decided that they need to sell a couple of them to
survive. BTW, the Antares flies sweetly as glider, as I hear from a
friend who can afford one. And isn't *that* the main criteria for a glider?

Stefan
Marc Ramsey
2006-06-01 20:51:33 UTC
Permalink
Post by Stefan
Post by Paul Remde
I wish I could afford one!
See? They probably decided that they need to sell a couple of them to
survive. BTW, the Antares flies sweetly as glider, as I hear from a
friend who can afford one. And isn't *that* the main criteria for a glider?
A glider that flies sweetly is a joy, but that criteria is pretty much
irrelevant if you can't afford to fly it...
Stefan
2006-06-01 22:04:29 UTC
Permalink
Post by Marc Ramsey
Post by Stefan
Post by Paul Remde
I wish I could afford one!
See? They probably decided that they need to sell a couple of them to
survive. BTW, the Antares flies sweetly as glider, as I hear from a
friend who can afford one. And isn't *that* the main criteria for a glider?
A glider that flies sweetly is a joy, but that criteria is pretty much
irrelevant if you can't afford to fly it...
Which was exactly my point.

Stefan
Jack
2006-06-01 22:33:00 UTC
Permalink
Post by Stefan
Post by Marc Ramsey
Post by Stefan
Post by Paul Remde
I wish I could afford one!
See? They probably decided that they need to sell a couple of them to
survive. BTW, the Antares flies sweetly as glider, as I hear from a
friend who can afford one. And isn't *that* the main criteria for a glider?
A glider that flies sweetly is a joy, but that criteria is pretty much
irrelevant if you can't afford to fly it...
Which was exactly my point.
Stefan
Be like me, buy a 1-26.

You won't have more fun in anything else -- you'll just temporarily fool
yourself into thinking you've become a better pilot simply by shredding
your checkbook.


Jack
#588
Eric Greenwell
2006-06-01 23:20:37 UTC
Permalink
Post by Jack
Post by Stefan
Post by Marc Ramsey
Post by Stefan
Post by Paul Remde
I wish I could afford one!
See? They probably decided that they need to sell a couple of them
to survive. BTW, the Antares flies sweetly as glider, as I hear from
a friend who can afford one. And isn't *that* the main criteria for
a glider?
A glider that flies sweetly is a joy, but that criteria is pretty
much irrelevant if you can't afford to fly it...
Which was exactly my point.
Stefan
Be like me, buy a 1-26.
You won't have more fun in anything else --
I can't speak for Stefan, but for me, unless it's one of those rare
self-launching 1-26M models - wrong!
Post by Jack
you'll just temporarily fool
yourself into thinking you've become a better pilot simply by shredding
your checkbook.
I do wonder how what percentage of pilots have gone from a 1-26 to a
higher performance glider, and were glad they did so, and what
percentage have gone from a higher performance glider to a 1-26, and
were glad they did so.

Personally, when I went from a Ka-6E to a Std Cirrus, I was pleased with
the additional soaring the higher performance allowed me. The next
significant increase in enjoyment occurred when I went from a "towed"
glider to a self-launching sailplane.
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Jack
2006-06-01 23:48:13 UTC
Permalink
Post by Eric Greenwell
Post by Jack
Be like me, buy a 1-26.
You won't have more fun in anything else --
I can't speak for Stefan, but for me, unless it's one of those rare
self-launching 1-26M models - wrong!
Post by Jack
you'll just temporarily fool yourself into thinking you've become a
better pilot simply by shredding your checkbook.
I do wonder how what percentage of pilots have gone from a 1-26 to a
higher performance glider, and were glad they did so, and what
percentage have gone from a higher performance glider to a 1-26, and
were glad they did so.
Personally, when I went from a Ka-6E to a Std Cirrus, I was pleased with
the additional soaring the higher performance allowed me. The next
significant increase in enjoyment occurred when I went from a "towed"
glider to a self-launching sailplane.
I see no conflict between our respective positions.

How fast you want to go = how much money you have. Neither has anything
to do with how good you are at doing whatever you can afford to do.

As far as going from higher performance to a 1-26, or any other glider,
there are a number of us on r.a.s. who have gone from much higher
performance aircraft (think mach+ and/or Boeing/McD/Airbus) to whatever
our current choices are and we know very well that performance is in the
stick actuator.

To each his own: have all the fun you can afford, I say.


Jack
Bill Daniels
2006-06-02 02:25:23 UTC
Permalink
Post by Eric Greenwell
Post by MaD
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
http://www.lange-flugzeugbau.de/english/menu/menu-akt.htm
The engine could be smaller but the battery pack almost the same size
as for the 20E would make it a *very* heavy 18m glider.
"Building a self-sustainer utilizing electrical propulsion is currently
not possible, because in order to achieve the range required for a
self-sustaining glider, the size of the battery-pack would have to be
comparable to the pack installed in the Antares 20E. This is contrary to
the basic idea behind a self sustaining glider, which is to provide a very
economical way of staying aloft."
I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E, but
weren't willing to accept a similar range limitation for a sustainer. I
suggest a sustainer that could climb 3000' on it's battery would be enough
for a majority of pilots, and this would allow a significantly smaller
battery to be used.
--
Change "netto" to "net" to email me directly
Eric Greenwell - Washington State, USA
www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Of course, a possible future alternative is a micro jet turbine. Roughly
speaking, the typical glider's 30 gallon ballast tanks, if converted to hold
Jet A, would give three hours at 120 knots. That would most likely get the
pilot to a comfortable landing spot in time for a steak and beer. I've done
the "back-of-envelope" nembers for my Nimbus 2C and they say it would do 120
knots for 7.5 hours with flameout near 18,000 feet.

Neither quiet nor green but effective.

Bill Daniels
Gary Emerson
2006-06-02 11:28:36 UTC
Permalink
Do you need (vs. want) to get home or do you need to get to the next
closest airport?
Post by Bill Daniels
Post by Eric Greenwell
Post by MaD
Post by d***@nadler.com
The 18T sustainer would be the sinky kind.
http://www.lange-flugzeugbau.de/english/menu/menu-akt.htm
The engine could be smaller but the battery pack almost the same size
as for the 20E would make it a *very* heavy 18m glider.
"Building a self-sustainer utilizing electrical propulsion is currently
not possible, because in order to achieve the range required for a
self-sustaining glider, the size of the battery-pack would have to be
comparable to the pack installed in the Antares 20E. This is contrary to
the basic idea behind a self sustaining glider, which is to provide a very
economical way of staying aloft."
I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E, but
weren't willing to accept a similar range limitation for a sustainer. I
suggest a sustainer that could climb 3000' on it's battery would be enough
for a majority of pilots, and this would allow a significantly smaller
battery to be used.
--
Change "netto" to "net" to email me directly
Eric Greenwell - Washington State, USA
www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Of course, a possible future alternative is a micro jet turbine. Roughly
speaking, the typical glider's 30 gallon ballast tanks, if converted to hold
Jet A, would give three hours at 120 knots. That would most likely get the
pilot to a comfortable landing spot in time for a steak and beer. I've done
the "back-of-envelope" nembers for my Nimbus 2C and they say it would do 120
knots for 7.5 hours with flameout near 18,000 feet.
Neither quiet nor green but effective.
Bill Daniels
MaD
2006-06-02 07:05:20 UTC
Permalink
Post by Eric Greenwell
I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E,
but weren't willing to accept a similar range limitation for a
sustainer. I suggest a sustainer that could climb 3000' on it's battery
would be enough for a majority of pilots, and this would allow a
significantly smaller battery to be used.
--
Yes, then the battery could be 1/3rd of the 20E-size. But:
No, I don't think 3000' would be widely accepted. That would only give
you an extra 60km range, so basically only good enough if you missed
the last thermal on your way home over flat country. In the Alps, with
two or three mountains between you and home: no good.

Marcel
Eric Greenwell
2006-06-02 16:22:57 UTC
Permalink
Post by MaD
Post by Eric Greenwell
I think it is odd they accepted the range limitations of an electric
system for the 20E, which has about 1/3 the powered range my ASH 26 E,
but weren't willing to accept a similar range limitation for a
sustainer. I suggest a sustainer that could climb 3000' on it's battery
would be enough for a majority of pilots, and this would allow a
significantly smaller battery to be used.
--
No, I don't think 3000' would be widely accepted. That would only give
you an extra 60km range, so basically only good enough if you missed
the last thermal on your way home over flat country. In the Alps, with
two or three mountains between you and home: no good.
So, not a good choice for the Alps, but two thirds of the USA (the part
east of the Rockies) doesn't have the "problem" of multiple tall
mountains. Even the Western USA has mostly mountains separated by wide
valleys with fields and airports.

Do the sustainer equipped gliders have enough altitude capability to get
over the mountains in the Alps, or does the pilot return by flying
through the valleys?
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Greg Arnold
2006-06-02 17:17:03 UTC
Permalink
Post by Eric Greenwell
Do the sustainer equipped gliders have enough altitude capability to get
over the mountains in the Alps, or does the pilot return by flying
through the valleys?
A very good question. It is my impression that the sustainers really
can't climb at all, and that you need to get a self-launching plane if
you want to get over a mountain.

There hasn't been much talk on RAS about the Apis electric
self-launcher, but it seems that it could work quite well as a
sustainer, and at a price that is much cheaper than the Antares.
Shawn
2006-06-02 17:24:12 UTC
Permalink
Post by Greg Arnold
Post by Eric Greenwell
Do the sustainer equipped gliders have enough altitude capability to
get over the mountains in the Alps, or does the pilot return by flying
through the valleys?
A very good question. It is my impression that the sustainers really
can't climb at all, and that you need to get a self-launching plane if
you want to get over a mountain.
There hasn't been much talk on RAS about the Apis electric
self-launcher, but it seems that it could work quite well as a
sustainer, and at a price that is much cheaper than the Antares.
A club member's Ventus b 16.6T could climb above 11,000 feet MSL with
his 16.6 tips (I saw him do it).

Shawn
Greg Arnold
2006-06-02 17:31:54 UTC
Permalink
Post by Shawn
Post by Greg Arnold
Post by Eric Greenwell
Do the sustainer equipped gliders have enough altitude capability to
get over the mountains in the Alps, or does the pilot return by
flying through the valleys?
A very good question. It is my impression that the sustainers really
can't climb at all, and that you need to get a self-launching plane if
you want to get over a mountain.
A club member's Ventus b 16.6T could climb above 11,000 feet MSL with
his 16.6 tips (I saw him do it).
Shawn
Do you know how long it took? At 100 fpm to 200 fpm, it could take a while.
Shawn
2006-06-03 05:44:56 UTC
Permalink
Post by Greg Arnold
Post by Shawn
Post by Greg Arnold
Post by Eric Greenwell
Do the sustainer equipped gliders have enough altitude capability to
get over the mountains in the Alps, or does the pilot return by
flying through the valleys?
A very good question. It is my impression that the sustainers really
can't climb at all, and that you need to get a self-launching plane
if you want to get over a mountain.
A club member's Ventus b 16.6T could climb above 11,000 feet MSL with
his 16.6 tips (I saw him do it).
Shawn
Do you know how long it took? At 100 fpm to 200 fpm, it could take a while.
I did forget to mention that didn't I? My Bad.

Shawn
5Z
2006-06-02 19:05:47 UTC
Permalink
Post by Shawn
A club member's Ventus b 16.6T could climb above 11,000 feet MSL with
his 16.6 tips (I saw him do it).
Here in Colorado, that would provide pattern altitude for many of the
areas I fly over!

When I've used the engine on my ASH-26E to get home it would stop
climbing at around 15K in the summer and over 16K in winter. The lower
ridges I need to cross are typically over 12K, so a climb to 15K is
generally good enough. But I'd be worried if much lower.

-Tom
Shawn
2006-06-03 05:52:25 UTC
Permalink
Post by 5Z
Post by Shawn
A club member's Ventus b 16.6T could climb above 11,000 feet MSL with
his 16.6 tips (I saw him do it).
Here in Colorado, that would provide pattern altitude for many of the
areas I fly over!
Leadville. Any other real strips?
He was over Salida BTW.

Shawn
Jeffrey Banks
2006-06-02 15:33:25 UTC
Permalink
With a very quiet ele thrust system, Would it be feasable
to dial in a lesser thrust setting to achieve an operational
higher performance polar? For example; a setting
for 'Nimbus 4' and another seting for 'ETA', and a
low setting for a 'Cirris'..... A charging mode to
achieve the polar of a 1-26 : )......


Jeff
5Z
2006-06-02 20:14:27 UTC
Permalink
Hey,
Nice writeup in this week's AOPA online mag.

-Tom
Andor Holtsmark
2006-06-03 20:28:32 UTC
Permalink
Hi everybody,
The discussion in this thread seems to revolve around
two points, which I feel require adressing.

(1) Antares might be great, but it is too expensive.

-If you look at the bottom line price of the Antares
20E, and then compare it to a similarily equipped glider
from another leading manufacturer, then the price difference
is not that big. As with all state of the art high
performance gliders, the sum which has to be paid is
not insignificant, but compared to other areas of aviation,
or automotive industry for that sake, you get a hell
of a lot of product for the money you pay when you
buy a glider. ..A lot of love goes into these machines.
Furthermore, when money really IS an issue, then one
might want to concider one more point: It might be
a good idea to invest in a toy which maintains a good
resale price. As with most pieces of equipment, this
is not always the 'el-cheapo' version.

(2) Antares 18T should come as an electrical self sustainer.

-The Antares 20E has an electrical propulsion system
because in the view of the designers, an electrical
propulsion system was the propulsion system which
fit the requirements for a self launcher the best.
For a self sustainer, the requirements are entirely
different, and at the current point in time, an internal
combustion system fits the requirements best. If one
today sets out to design an electric self sustainer,
one would basically end up with a Antares 20E with
shorter wings, smaller engine, and possible far to
short range. But most importantly: the price would
be that of the 20E. There is no market for such a plane.


..Just my two pennies worth..

Andor
Eric Greenwell
2006-06-03 21:51:12 UTC
Permalink
Post by Andor Holtsmark
(2) Antares 18T should come as an electrical self sustainer.
-The Antares 20E has an electrical propulsion system because in the
view of the designers, an electrical propulsion system was the
propulsion system which fit the requirements for a self launcher the
best.
I'm wondering how you know the designers' view - did the designers tell
you directly? In any case, I don't think it's the self-launcher that
sets the requirements, but really the customer. As you know, there are
many pilots that prefer the gasoline engine self-launcher because it is
much lighter and has a much greater range.
Post by Andor Holtsmark
For a self sustainer, the requirements are entirely different, and at
the current point in time, an internal combustion system fits the
requirements best. If one today sets out to design an electric self
sustainer, one would basically end up with a Antares 20E with shorter
wings,
They have already designed this - the 18 meter model!
Post by Andor Holtsmark
smaller engine, and possible far to short range.
It sounds like some pilots would accept the shorter range in exchange
for the simplicity and reliability of an electric system, just as some
pilots have accepted the shorter range of the 20E.
Post by Andor Holtsmark
But most importantly: the price would
be that of the 20E. There is no market for such a plane.
With a motor and a battery back one-third the size of the 20E, it would
cheaper; even so, there may not be a large enough market for such a
glider. I am curious: how did the factory decide the market was too
small? World wide pilot survey? Focus group? Wild guess?
--
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
2006-06-04 15:13:18 UTC
Permalink
Post by Eric Greenwell
I'm wondering how you know the designers' view - did
the designers tell
you directly?
-I happen to be employed as an engineer at a small
company named Lange Flugzeugbau. I did not work there
when the decision was made to go electric, but in my
view it was a correct decision. Please note that what
I write here are my personal opinions, which should
not in any way be mistaken with the official view of
Lange Flugzeugbau.
Post by Eric Greenwell
In any case, I don't think it's the self-launcher that
sets the requirements, but really the customer. As
you know, there are
many pilots that prefer the gasoline engine self-launcher
because it is
much lighter and has a much greater range.
-Self launching is a task. An aircraft is a system
optimized for one or more tasks. Self launching is
a way to get airborne and reach thermaling altitude
easily and with a minimum of hazzle. The 20E performs
this task beautifully. How often do you need 3000 m
climb altitude to enter your first thermal? In my experience,
500-800 m should be enough. This should in most cases
leave you with quite a bit of energy to get home with,
or at least to the nearest airfield.. or if you really
have messed things up, to a landable area. It should
here be noted that if you happen to be high, then an
electrical propulsion system is superior to an internal
combustion based one, since the engine is unaffected
by altitude, and the propeller only is minimally affected.


Now.. If you plan to regularily turn on the engine
and shake for 2-3 hours, then you should buy a Cessna.
The self sustainer concept (in general) was meant as
a way to get home that one day in the year when the
thermals end and you have only flown 800 out of the
planned 1000 km. It was not meant for regular use.
Post by Eric Greenwell
They have already designed this - the 18 meter model!
-The 18m wingtips for the 20E have been removed from
the options list due to lack of costumer interrest.
The 18T will, as previously mentioned utilize a stinky
engine
Post by Eric Greenwell
It sounds like some pilots would accept the shorter
range in exchange
for the simplicity and reliability of an electric system,
just as some
pilots have accepted the shorter range of the 20E.
-I would not base my whole sales strategy on that estimate.
Post by Eric Greenwell
With a motor and a battery back one-third the size
of the 20E, it would
cheaper;
-Motor and battery pack 1/3 the size of the 20E would
yield a very short range, but have a dissapointingly
small effect on the end price of the product. For the
batteries; we have a very good deal with the manufactures.
For the engine; material cost is not the driving factor.
An engine 1/3 the size of the EA42 will not have 1/3
the price. What is also forgotten here, is that the
propulsion system consists of a lot more than just
batteries and engine. All the other systems, like charger,
power electronics and main computer would not be effected
at all by the 1/3 effect.
Post by Eric Greenwell
I am curious: how did the factory decide the market
was too
small? World wide pilot survey? Focus group? Wild guess?
-Tons of experience, logic and deduction I presume
;)

Andor
Greg Arnold
2006-06-04 15:59:00 UTC
Permalink
Andor, since you no longer offer the 18m tips for the 20E, it would seem
there is no reason to keep the junction between the inner and outer wing
panels out toward the tip. Have you considered moving the junction
further inboard so the glider will fit in a shorter trailer?
Post by Andor Holtsmark
Post by Eric Greenwell
I'm wondering how you know the designers' view - did
the designers tell
you directly?
-I happen to be employed as an engineer at a small
company named Lange Flugzeugbau. I did not work there
when the decision was made to go electric, but in my
view it was a correct decision. Please note that what
I write here are my personal opinions, which should
not in any way be mistaken with the official view of
Lange Flugzeugbau.
Post by Eric Greenwell
In any case, I don't think it's the self-launcher that
sets the requirements, but really the customer. As
you know, there are
many pilots that prefer the gasoline engine self-launcher
because it is
much lighter and has a much greater range.
-Self launching is a task. An aircraft is a system
optimized for one or more tasks. Self launching is
a way to get airborne and reach thermaling altitude
easily and with a minimum of hazzle. The 20E performs
this task beautifully. How often do you need 3000 m
climb altitude to enter your first thermal? In my experience,
500-800 m should be enough. This should in most cases
leave you with quite a bit of energy to get home with,
or at least to the nearest airfield.. or if you really
have messed things up, to a landable area. It should
here be noted that if you happen to be high, then an
electrical propulsion system is superior to an internal
combustion based one, since the engine is unaffected
by altitude, and the propeller only is minimally affected.
Now.. If you plan to regularily turn on the engine
and shake for 2-3 hours, then you should buy a Cessna.
The self sustainer concept (in general) was meant as
a way to get home that one day in the year when the
thermals end and you have only flown 800 out of the
planned 1000 km. It was not meant for regular use.
Post by Eric Greenwell
They have already designed this - the 18 meter model!
-The 18m wingtips for the 20E have been removed from
the options list due to lack of costumer interrest.
The 18T will, as previously mentioned utilize a stinky
engine
Post by Eric Greenwell
It sounds like some pilots would accept the shorter
range in exchange
for the simplicity and reliability of an electric system,
just as some
pilots have accepted the shorter range of the 20E.
-I would not base my whole sales strategy on that estimate.
Post by Eric Greenwell
With a motor and a battery back one-third the size
of the 20E, it would
cheaper;
-Motor and battery pack 1/3 the size of the 20E would
yield a very short range, but have a dissapointingly
small effect on the end price of the product. For the
batteries; we have a very good deal with the manufactures.
For the engine; material cost is not the driving factor.
An engine 1/3 the size of the EA42 will not have 1/3
the price. What is also forgotten here, is that the
propulsion system consists of a lot more than just
batteries and engine. All the other systems, like charger,
power electronics and main computer would not be effected
at all by the 1/3 effect.
Post by Eric Greenwell
I am curious: how did the factory decide the market
was too
small? World wide pilot survey? Focus group? Wild guess?
-Tons of experience, logic and deduction I presume
;)
Andor
d***@nadler.com
2006-06-04 16:23:41 UTC
Permalink
Slight clarification to Andor's comment: the 18-meter tips
for the 20E will not be certified, but offered for US market
experimental depending on demand. I will have a set...
Best Regards, Dave
Post by Greg Arnold
Andor, since you no longer offer the 18m tips for the 20E, it would seem
there is no reason to keep the junction between the inner and outer wing
panels out toward the tip. Have you considered moving the junction
further inboard so the glider will fit in a shorter trailer?
Post by Andor Holtsmark
Post by Eric Greenwell
I'm wondering how you know the designers' view - did
the designers tell
you directly?
-I happen to be employed as an engineer at a small
company named Lange Flugzeugbau. I did not work there
when the decision was made to go electric, but in my
view it was a correct decision. Please note that what
I write here are my personal opinions, which should
not in any way be mistaken with the official view of
Lange Flugzeugbau.
Post by Eric Greenwell
In any case, I don't think it's the self-launcher that
sets the requirements, but really the customer. As
you know, there are
many pilots that prefer the gasoline engine self-launcher
because it is
much lighter and has a much greater range.
-Self launching is a task. An aircraft is a system
optimized for one or more tasks. Self launching is
a way to get airborne and reach thermaling altitude
easily and with a minimum of hazzle. The 20E performs
this task beautifully. How often do you need 3000 m
climb altitude to enter your first thermal? In my experience,
500-800 m should be enough. This should in most cases
leave you with quite a bit of energy to get home with,
or at least to the nearest airfield.. or if you really
have messed things up, to a landable area. It should
here be noted that if you happen to be high, then an
electrical propulsion system is superior to an internal
combustion based one, since the engine is unaffected
by altitude, and the propeller only is minimally affected.
Now.. If you plan to regularily turn on the engine
and shake for 2-3 hours, then you should buy a Cessna.
The self sustainer concept (in general) was meant as
a way to get home that one day in the year when the
thermals end and you have only flown 800 out of the
planned 1000 km. It was not meant for regular use.
Post by Eric Greenwell
They have already designed this - the 18 meter model!
-The 18m wingtips for the 20E have been removed from
the options list due to lack of costumer interrest.
The 18T will, as previously mentioned utilize a stinky
engine
Post by Eric Greenwell
It sounds like some pilots would accept the shorter
range in exchange
for the simplicity and reliability of an electric system,
just as some
pilots have accepted the shorter range of the 20E.
-I would not base my whole sales strategy on that estimate.
Post by Eric Greenwell
With a motor and a battery back one-third the size
of the 20E, it would
cheaper;
-Motor and battery pack 1/3 the size of the 20E would
yield a very short range, but have a dissapointingly
small effect on the end price of the product. For the
batteries; we have a very good deal with the manufactures.
For the engine; material cost is not the driving factor.
An engine 1/3 the size of the EA42 will not have 1/3
the price. What is also forgotten here, is that the
propulsion system consists of a lot more than just
batteries and engine. All the other systems, like charger,
power electronics and main computer would not be effected
at all by the 1/3 effect.
Post by Eric Greenwell
I am curious: how did the factory decide the market
was too
small? World wide pilot survey? Focus group? Wild guess?
-Tons of experience, logic and deduction I presume
;)
Andor
Eric Greenwell
2006-06-04 17:11:58 UTC
Permalink
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.

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.
Post by Andor Holtsmark
-Self launching is a task. An aircraft is a system
optimized for one or more tasks.Self launching is
a way to get airborne and reach thermaling altitude
easily and with a minimum of hazzle. The 20E performs
this task beautifully.
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.
Post by Andor Holtsmark
How often do you need 3000 m
climb altitude to enter your first thermal?
Perhaps twice a year, but not always to a thermal, but sometimes to
enter a wave.
Post by Andor Holtsmark
In my experience,
500-800 m should be enough. This should in most cases
leave you with quite a bit of energy to get home with,
or at least to the nearest airfield..
Almost always, in my experience.
Post by Andor Holtsmark
or if you really
have messed things up, to a landable area. It should
here be noted that if you happen to be high, then an
electrical propulsion system is superior to an internal
combustion based one, since the engine is unaffected
by altitude, and the propeller only is minimally affected.
Now.. If you plan to regularily turn on the engine
and shake for 2-3 hours, then you should buy a Cessna.
Or perhaps a Stemme? Or a Carat? My point is "self-launching" does not
set the requirements, but the intended customer. Lange may be correct
that it would not be profitable to market an 18 M electric sustainer. I
hope they are wrong.
Post by Andor Holtsmark
The self sustainer concept (in general) was meant as
a way to get home that one day in the year when the
thermals end and you have only flown 800 out of the
planned 1000 km. It was not meant for regular use.
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? 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!
--
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
2006-06-05 13:23:06 UTC
Permalink
Post by Eric Greenwell
While this discussion (which I continue below) is an
interesting one, it
mostly side-steps the RAS response to the announcement
that Lange will
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.
Post by Eric Greenwell
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?
Post by Eric Greenwell
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.
Post by Eric Greenwell
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?
Post by Eric Greenwell
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
Eric Greenwell
2006-06-05 15:04:02 UTC
Permalink
Post by Andor Holtsmark
Post by Eric Greenwell
While this discussion (which I continue below) is an
interesting one, it
mostly side-steps the RAS response to the announcement
that Lange will
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"
Stefan
2006-06-05 15:29:43 UTC
Permalink
Post by Eric Greenwell
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
Shawn
2006-06-05 15:12:12 UTC
Permalink
Post by Andor Holtsmark
Post by Eric Greenwell
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
Tony Verhulst
2006-06-05 23:08:42 UTC
Permalink
Post by Shawn
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.
Eric Greenwell
2006-06-05 23:25:59 UTC
Permalink
Post by Tony Verhulst
Post by Shawn
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"
2cernauta2
2006-06-06 00:20:14 UTC
Permalink
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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
Greg Arnold
2006-06-06 02:54:09 UTC
Permalink
Post by 2cernauta2
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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.
Bill Daniels
2006-06-06 13:42:34 UTC
Permalink
Post by Greg Arnold
Post by 2cernauta2
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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.
Small 2-stroke engines which require oil mixed with the fuel will often have
startng problems after long periods of inactivity. The fuel/oil mix forms
gum in the small passages inside the carburator blocking them. I understand
there are spicific 2-stroke oils that reduce but do not eliminate this
problem. The cure is to dismantle the fuel system and clean it with
solvent.

I wouldn't expect a weed eater, snow blower, or lawn mower that has sat with
fuel in it for 6 months or so to start easily. Sustainer engines are no
different.

Bill Daniels
Shawn
2006-06-06 16:13:15 UTC
Permalink
Post by Bill Daniels
Post by Greg Arnold
Post by 2cernauta2
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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.
Small 2-stroke engines which require oil mixed with the fuel will often have
startng problems after long periods of inactivity. The fuel/oil mix forms
gum in the small passages inside the carburator blocking them. I understand
there are spicific 2-stroke oils that reduce but do not eliminate this
problem. The cure is to dismantle the fuel system and clean it with
solvent.
I wouldn't expect a weed eater, snow blower, or lawn mower that has sat with
fuel in it for 6 months or so to start easily. Sustainer engines are no
different.
Guess I picked up on a few out-of-the-norm complaints and assumed they
were typical.
Seems like a preflight run-up of the engine would reveal/mitigate many
starting problems in flight.

BTW, my string trimmer was a pill to start this spring :-p

Shawn
Ruud
2006-06-06 11:26:49 UTC
Permalink
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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.
Charles Yeates
2006-06-06 12:14:54 UTC
Permalink
AT Parowan last June, one supper conversation with three owners of
powered single seaters detailed two propeller problems (manufacturer
took a season to sort out) and one battery failure (expensive) --
unusual, I suppose. But not engine problems, eh?
Post by 2cernauta2
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
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.
Eric Greenwell
2006-06-06 15:25:38 UTC
Permalink
Post by Charles Yeates
AT Parowan last June, one supper conversation with three owners of
powered single seaters detailed two propeller problems (manufacturer
took a season to sort out) and one battery failure (expensive) --
unusual, I suppose. But not engine problems, eh?
Were these all two stroke engines? And I'm very curious how a battery
failure could be expensive, given the low cost of batteries.
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Charles Yeates
2006-06-06 17:47:38 UTC
Permalink
I was told the engine start battery replacement cost $1,000
Post by Eric Greenwell
Post by Charles Yeates
AT Parowan last June, one supper conversation with three owners of
powered single seaters detailed two propeller problems (manufacturer
took a season to sort out) and one battery failure (expensive) --
unusual, I suppose. But not engine problems, eh?
Were these all two stroke engines? And I'm very curious how a battery
failure could be expensive, given the low cost of batteries.
Eric Greenwell
2006-06-06 18:25:14 UTC
Permalink
Post by Charles Yeates
Post by Eric Greenwell
Post by Charles Yeates
AT Parowan last June, one supper conversation with three owners of
powered single seaters detailed two propeller problems (manufacturer
took a season to sort out) and one battery failure (expensive) --
unusual, I suppose. But not engine problems, eh?
Were these all two stroke engines? And I'm very curious how a battery
failure could be expensive, given the low cost of batteries.
I was told the engine start battery replacement cost $1,000
Wow! What glider was it? And is that the price of the battery, or is
there a terrific amount of labor involved in changing it?
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Marc Ramsey
2006-06-05 15:21:49 UTC
Permalink
Post by Andor Holtsmark
-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...
Andor Holtsmark
2006-06-06 17:45:33 UTC
Permalink
Post by 2cernauta2
On Mon, 05 Jun 2006 09:12:12 -0600, Shawn
Post by Shawn
Why are these two stroke engines so notoriously unreliable?
-I just want to clarify that I did not ask this question.
I asked about how many self sustainers used regularily
hour after hour suffers from engine trouble. I hope
the difference is clear.
I am not trying to imply that this must happen, I am
curious about what the experiences are.

Andor
Gary Evans
2006-06-06 19:09:14 UTC
Permalink
My DG808B self-launcher uses 4 sealed batteries and
they all can be replaced for less than $80 which I
believe is typical. The batteries are cheap enough
that I replace them every two years regardless of condition.
There is no gas powered glider that I know of with
a $1000 battery but perhaps an electric self-launcher
battery could be that expensive.
Reliability and maintenance on any powered glider is
going to be significantly more of an issue than a pure
glider. It isn't like buying a Chevrolet where the
various systems have been refined over a long period
of time. The fuel/electrical systems used today are
pretty crude compared to modern automotive design but
given enough attention and preventive maintenance they
perform pretty well. Routine operation is a very good
idea regardless if it’s a self-launcher or sustainer.
With the exception of one loss of electrical power
mine has never failed to start or in flight after 325
frame and 25 engine hours. In that same period I have
experienced 4 rope breaks on tow so the self-launcher
reliability looks pretty good to me.
Post by Charles Yeates
I was told the engine start battery replacement cost
$1,000
Post by Eric Greenwell
Post by Charles Yeates
AT Parowan last June, one supper conversation with
three owners of
powered single seaters detailed two propeller problems
(manufacturer
took a season to sort out) and one battery failure
(expensive) --
unusual, I suppose. But not engine problems, eh?
Were these all two stroke engines? And I'm very curious
how a battery
failure could be expensive, given the low cost of
batteries.
Charles Yeates
2006-06-06 20:19:37 UTC
Permalink
Maybe the high figure is what he told his wife??
Post by Gary Evans
My DG808B self-launcher uses 4 sealed batteries and
they all can be replaced for less than $80 which I
believe is typical. The batteries are cheap enough
that I replace them every two years regardless of condition.
There is no gas powered glider that I know of with
a $1000 battery but perhaps an electric self-launcher
battery could be that expensive.
Reliability and maintenance on any powered glider is
going to be significantly more of an issue than a pure
glider. It isn't like buying a Chevrolet where the
various systems have been refined over a long period
of time. The fuel/electrical systems used today are
pretty crude compared to modern automotive design but
given enough attention and preventive maintenance they
perform pretty well. Routine operation is a very good
idea regardless if it’s a self-launcher or sustainer.
With the exception of one loss of electrical power
mine has never failed to start or in flight after 325
frame and 25 engine hours. In that same period I have
experienced 4 rope breaks on tow so the self-launcher
reliability looks pretty good to me.
MaD
2006-06-08 11:33:41 UTC
Permalink
Post by Gary Evans
...
With the exception of one loss of electrical power
mine has never failed to start or in flight after 325
frame and 25 engine hours. In that same period I have
experienced 4 rope breaks on tow ...
Good heavens!!!
I strongly suggest you start using different ropes!

Marcel
Andy Blackburn
2006-06-07 17:55:03 UTC
Permalink
Post by Shawn
Seems like a preflight run-up of the engine would reveal/mitigate
many
starting problems in flight.
My thought exactly.

There have been some comments here that sustainers
generally are not run up prior to flights (presumably
including flights where use of the engine is a distinct
possibility) AND that periods of inactivity significantly
up the odds of the engine failing to start.

If both of these statements are true it seems that
flying a sustainer-equipped sailplane cross-country
without a preflight engine runup is a bit of a roll
of the dice. It also raises in my mind two somewhat
related questions:

1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?

2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care, do they presume that the engine IS likely to
start (correctly or incorrectly), or do they believe
a preflight runup doesn't help the odds anyway.

Thoughts?

9B
Eric Greenwell
2006-06-07 18:33:28 UTC
Permalink
Post by Andy Blackburn
Post by Shawn
Seems like a preflight run-up of the engine would reveal/mitigate
many
starting problems in flight.
My thought exactly.
There have been some comments here that sustainers
generally are not run up prior to flights (presumably
including flights where use of the engine is a distinct
possibility) AND that periods of inactivity significantly
up the odds of the engine failing to start.
If both of these statements are true it seems that
flying a sustainer-equipped sailplane cross-country
without a preflight engine runup is a bit of a roll
of the dice. It also raises in my mind two somewhat
1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?
2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care, do they presume that the engine IS likely to
start (correctly or incorrectly), or do they believe
a preflight runup doesn't help the odds anyway.
Besides the issue of the engine readiness, there is the issue of pilot
readiness: if the pilot hasn't started the engine in the air recently,
isn't he more likely to bungle the start when he getting low and under
pressure? Even better than a preflight, on-the-ground start, would be to
do it after releasing from the launch. You could even take lower
aerotow, and save a bunch on the tow fee.
--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"
Stefan
2006-06-07 18:47:59 UTC
Permalink
Post by Andy Blackburn
1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?
Yes. It has no starter. (And, btw: Even if it had one, the simple fact
that it starts *now* doesn't mean that it will start *then*.)
Post by Andy Blackburn
2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care,
Yes and no. Yes, flying a sustainer we *always* presume that the engine
is unlikely to start. And no, we actually care. Thats why we never rely
on a ststainer but only start the engine over a landable field.

Stefan
Shawn
2006-06-07 19:00:12 UTC
Permalink
Post by Stefan
Post by Andy Blackburn
1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?
Yes. It has no starter. (And, btw: Even if it had one, the simple fact
that it starts *now* doesn't mean that it will start *then*.)
I know some or all start in the air by windmilling. Is there a pull
string starter or the ability to hand-prop on the ground?

Your statement about "the simple fact that it starts *now* doesn't mean
that it will start *then*" is unassailable, however the odds may
improve. If it *doesn't* start now would be a good reason to not expect
it to start in the air ;-)

Shawn
Andy Blackburn
2006-06-07 17:55:11 UTC
Permalink
Post by Shawn
Seems like a preflight run-up of the engine would reveal/mitigate
many
starting problems in flight.
My thought exactly.

There have been some comments here that sustainers
generally are not run up prior to flights (presumably
including flights where use of the engine is a distinct
possibility) AND that periods of inactivity significantly
up the odds of the engine failing to start.

If both of these statements are true it seems that
flying a sustainer-equipped sailplane cross-country
without a preflight engine runup is a bit of a roll
of the dice. It also raises in my mind two somewhat
related questions:

1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?

2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care, do they presume that the engine IS likely to
start (correctly or incorrectly), or do they believe
a preflight runup doesn't help the odds anyway.

Thoughts?

9B
John Ferguson
2006-06-07 18:33:54 UTC
Permalink
I don't believe that there is anything wrong or suspect
with two stroke engines. You do have to be careful
with them, here are the things that I've learned from
motorbikes and glider turbos

Use the best sparkplugs you can get to avoid two stroke
whiskering, try platinum or exotic equivalent

Take care of your plugs

Do a DI of your engine before flight, are all the bits
there, eg, the HT leads are ON

Take scrupulous care with your fuel/2 stroke mixing

Prime your engine before takeoff

Start your engine before starting task, 2nd starts
are always much quicker for some reason

Remember the sequence fuel on, erect, ignition, TE
change over, push prime, pull decomp speed up and release.

Sounds dificult but it isn't with practice - this on
a Ventus c so its a bit old tech compared to ASW 28
and ASG 29s or DG1000s.

After a couple of months layoff the engine is much
slower to start and needs determined effort to get
it going. I presume that it needs to blow oil out of
the crankcase and cylinders.

John
John Ferguson
2006-06-07 18:34:30 UTC
Permalink
I don't believe that there is anything wrong or suspect
with two stroke engines. You do have to be careful
with them, here are the things that I've learned from
motorbikes and glider turbos

Use the best sparkplugs you can get to avoid two stroke
whiskering, try platinum or exotic equivalent

Take care of your plugs

Do a DI of your engine before flight, are all the bits
there, eg, the HT leads are ON

Take scrupulous care with your fuel/2 stroke mixing

Prime your engine before takeoff

Start your engine before starting task, 2nd starts
are always much quicker for some reason

Remember the sequence fuel on, erect, ignition, TE
change over, push prime, pull decomp speed up and release.

Sounds dificult but it isn't with practice - this on
a Ventus c so its a bit old tech compared to ASW 28
and ASG 29s or DG1000s.

After a couple of months layoff the engine is much
slower to start and needs determined effort to get
it going. I presume that it needs to blow oil out of
the crankcase and cylinders.

John
Z Goudie
2006-06-07 20:56:26 UTC
Permalink
Never had a problem with my Discus Turbo (apart from
finger trouble).

Always prime it. Always start and run it for at least
20 secs before leaving site/starting task.

Has anyone mentioned that it confirms that the logger
engine noise sensor has worked properly?
Andy Blackburn
2006-06-08 10:01:40 UTC
Permalink
Post by Stefan
Post by Andy Blackburn
1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?
Yes. It has no starter. (And, btw: Even if it had one,
the simple fact
that it starts *now* doesn't mean that it will start
*then*.)
My bad - never looked closely enough at a Turbo.
Post by Stefan
Post by Andy Blackburn
2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care,
Yes and no. Yes, flying a sustainer we *always* presume
that the engine
is unlikely to start. And no, we actually care. Thats
why we never rely
on a ststainer but only start the engine over a landable
field.
That part I know. I was trying to ask a slightly different
question, which is: if sustainers are less reliable
on a first start than a second start and pilots don't
do some sort of runup prior to heading out on course
is it that they just don't care that much if the engine
fails to start when called upon - forcing them to land
out? Or is it that they don't believe the second start
story? Or do most pilots actually do a runup (from
an air start of course!), prior to going out on course?

9B
Bert Willing
2006-06-08 11:00:46 UTC
Permalink
Well, if you want to score your flight anywhere, you need to have the engine
in operation somewhere during the log so that the engine noise/vibration
sensor is verified.
You can do that after returning home, of course, but it would be more
sensible to do that before leaving.
Post by Andy Blackburn
Post by Stefan
Post by Andy Blackburn
1) Is there a good reason why one shouldn't do a runup
prior to every (cross-country) flight?
Yes. It has no starter. (And, btw: Even if it had one,
the simple fact
that it starts *now* doesn't mean that it will start
*then*.)
My bad - never looked closely enough at a Turbo.
Post by Stefan
Post by Andy Blackburn
2) Do many pilots flying sustainer-equipped sailplanes
presume that the engine is unlikely to start and not
care,
Yes and no. Yes, flying a sustainer we *always* presume
that the engine
is unlikely to start. And no, we actually care. Thats
why we never rely
on a ststainer but only start the engine over a landable
field.
That part I know. I was trying to ask a slightly different
question, which is: if sustainers are less reliable
on a first start than a second start and pilots don't
do some sort of runup prior to heading out on course
is it that they just don't care that much if the engine
fails to start when called upon - forcing them to land
out? Or is it that they don't believe the second start
story? Or do most pilots actually do a runup (from
an air start of course!), prior to going out on course?
9B
Gary Evans
2006-06-08 14:11:14 UTC
Permalink
Now you suggest that.
Post by MaD
Post by Gary Evans
...
With the exception of one loss of electrical power
mine has never failed to start or in flight after
325
frame and 25 engine hours. In that same period I have
experienced 4 rope breaks on tow ...
Good heavens!!!
I strongly suggest you start using different ropes!
Marcel
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