Self-launch v Sustainer

Thanks for the detailed comments . There are several considerations still on the table (I have 500hrs including several hours in a Duo-Discus). My ideal motorized glider: 2-seater, easy to assemble, good trailer, dependable FES or non-pyloned powerplant, electric self-launcher (would settle for sustainer), good maneuverability. Trading-off on some features (other than my wife), the Stemme, Arcus M/T and Pipistrel Taurus electric both seem to come pretty close. I might consider a Stemme, but there doesn't seem to be many used VT's (better climb v S10), and as Dan mentioned, it doesn't maneuver like a 15m. Those are both out of my price range new. Other than Dave, there wasn't much discussion about sustainers. The numbers seem a bit tedious to find, so in general what is the weight penalty between self-launchers and sustainers? Reliability the same? Faster deployment? Yes, I would consider a single-place which would give more options. The newer electrics are compelling, but one might be waiting awhile to grab one. Aside from the deployment time, do they have a weight advantage as well (including Li batteries)? Dave's presentation included reference to a 30% incidence of engine failure (2-stroke?). Electrics must be an improvement over that, presumably. I have read Eric Greenwell's excellent articles at the ASA. https://groups.yahoo.com/neo/groups/ASA-NewsGroup/info
Thanks again,
Mike

On Sat, 29 Oct 2016 21:11:26 +0000, Dave Walsh
wrote:


If just a self launch (and you are willing to put up with possibly
unreliable two strokes) then: -

Nimbus 3DM (doesn't go round corners easily)
Nimbus 4DM (an amazing bit of kit; a few have suffered wing
structural failures; also doesn't go round corners readily)
DG500M (competent, getting on in years, not as nice to fly as
a Duo).

.... not mention the nicest self launchers with the best engine systems
out the
ASH-25 Mi, its successot ASH-30 Mi and the 20m ASG-32 Mi.

Al open class gliders feel as if they "don't go around corners
easily", but that's not true and simply a question of experience.



Turbos: Plenty of choices: Duo Discus; DG1000; Arcus, Nimbus
3DT/4DT; Arcus E. I've never flown any of them but the
standard Duo is a delight. Doubtless some one will be along
soon to extol the virtues of Turbos.

I've flown all of them - all are nice.

Main problem of all open class gliders is the assembly which takes
considerable experience, time and sometimes simply a lot of strength.

Double seaters are a little better, but still heavy and, compared to
any single seater, cumbersome to assemble. One needs to think twice
about such a glider.

On Monday, October 31, 2016 at 12:06:03 PM UTC-7, Duster wrote:
Thanks for the detailed comments . There are several considerations still on the table (I have 500hrs including several hours in a Duo-Discus). My ideal motorized glider: 2-seater, easy to assemble, good trailer, dependable FES or non-pyloned powerplant, electric self-launcher (would settle for sustainer), good maneuverability. Trading-off on some features (other than my wife), the Stemme, Arcus M/T and Pipistrel Taurus electric both seem to come pretty close. I might consider a Stemme, but there doesn't seem to be many used VT's (better climb v S10), and as Dan mentioned, it doesn't maneuver like a 15m. Those are both out of my price range new. Other than Dave, there wasn't much discussion about sustainers. The numbers seem a bit tedious to find, so in general what is the weight penalty between self-launchers and sustainers? Reliability the same? Faster deployment? Yes, I would consider a single-place which would give more options. The newer electrics are compelling, but one might be waiting awhile to grab one. Aside from the deployment time, do they have a weight advantage as well (including Li batteries)? Dave's presentation included reference to a 30% incidence of engine failure (2-stroke?). Electrics must be an improvement over that, presumably. I have read Eric Greenwell's excellent articles at the ASA. https://groups.yahoo.com/neo/groups/ASA-NewsGroup/info
Thanks again,
Mike

Good thoughts.
How easy is it to put a Stemme in the trailer? Most of them don't have trailers, and the enormous Cobra trailer includes some complicated bits.
Agree with Andreas' comments re ASH25Mi, etc. Hope to fly a 32 this week.
The 25 feels just like any of the others in the AS line after a short while..
The N4DM is also easy to fly but I have not rigged one and personally don't care for two-stroke engines in aircraft.
Mike, in the "you only live once" spirit... Go for the Arcus JET!
Jim

On Monday, October 31, 2016 at 1:06:03 PM UTC-6, Duster wrote:
Thanks for the detailed comments . There are several considerations still on the table (I have 500hrs including several hours in a Duo-Discus). My ideal motorized glider: 2-seater, easy to assemble, good trailer, dependable FES or non-pyloned powerplant, electric self-launcher (would settle for sustainer), good maneuverability. Trading-off on some features (other than my wife), the Stemme, Arcus M/T and Pipistrel Taurus electric both seem to come pretty close. I might consider a Stemme, but there doesn't seem to be many used VT's (better climb v S10), and as Dan mentioned, it doesn't maneuver like a 15m. Those are both out of my price range new. Other than Dave, there wasn't much discussion about sustainers. The numbers seem a bit tedious to find, so in general what is the weight penalty between self-launchers and sustainers? Reliability the same? Faster deployment? Yes, I would consider a single-place which would give more options. The newer electrics are compelling, but one might be waiting awhile to grab one. Aside from the deployment time, do they have a weight advantage as well (including Li batteries)? Dave's presentation included reference to a 30% incidence of engine failure (2-stroke?). Electrics must be an improvement over that, presumably. I have read Eric Greenwell's excellent articles at the ASA. https://groups.yahoo.com/neo/groups/ASA-NewsGroup/info
Thanks again,
Mike

Mike- Regarding electric sustainers and specifically the FES, please let me know exactly what questions you may have. I have owned my LAK-17B FES for 5 years and hopefully, I can help you with answers on any questions you may have. BTW, there is no deployment time on the FES as it turns on immediately like when you turn on a ceiling fan. Now, we know nothing is 100% reliable, but in 5 years and dozens of starts on the ground and in the air, it has never failed me! Finally on system weight, the total, including the 2 each, LI-Po batteries, motor and prop, adds approx 85 pounds to the weight of the glider.

Finally, as I have previously written in this thread, you can find a lot more detailed FES info at:

http://www.front-electric-sustainer.com/

Thanks - Renny

Some interesting posts; but if there were a simple answer to
the original question then we'd all be flying it.

The Stemme S10, Arcus variants and the Pipistrel Taurus are
wildly different animals: it's hard to imagine a particular pilot
putting those 3 onto their "short list"!
Only the Stemme has any useful range. The Taurus with two
well built pilots on board will always be bottom of the
thermal. Scratching in weak hill lift in the Stemme is hard
work; 23m with fuel in the wings is just not enjoyable.
By all accounts the Arcus variants (excepting the Arcus E)
are a delight.
My view is that it's hard to accept inferior performance,
especially when you're paying for it. Anyone who has
sampled Nimbus 4, Arcus, Duo performance in the
mountains is not going to want to scratch around in a
Taurus.
I am not knocking the Taurus, it has good take off
performance and in Europe falls into the "Ultralight" category
so enormous advantages in cost, maintenance and licensing
areas. It also has a reliable Rotax engine, another huge plus.
By all accounts it is very nice to fly.

If I were buying a Stemme I'd actively look for the earlier
Limbach engined version; sure the power performance of the
VT is better but not needed unless "hot and high" is always
on the agenda. Some might argue that the earlier version
was more reliable?

As self launch single seaters get a mention in earlier posts
here's my two Euros worth: the ASH26E (and other Wankel
engined machines) are capable of prolonged straight and
level flight to "get you home". All the rest, powered by two
cylinder two strokes, (DG800, Ventus CM etc) require "climb
and glide"......
Note the Wankel engine has its own issues. A prospective
purchaser should join the various "User Groups": LOTS of
issues with Wankel, Solo and Rotax engines are highlighted
there.

On Monday, October 31, 2016 at 3:06:03 PM UTC-4, Duster wrote:
Dave's presentation included reference to a
30% incidence of engine failure (2-stroke?).

To be clear, that includes any failure of the propulsion system,
which can be mechanisms for extension, prop-centering, retraction,
starting, exhaust or structural cracking, etc.
Rarely the core of the engine...

These are not Toyotas, and if you fly like they won't die, you well may.

Hope that helps,
Best Regards, Dave

The Stemme is easy to rig. I rig mine solo in about 9 minutes with no
need for any rigging aids. Of course, I keep it in a hangar and have
never taken the center section off, though I've seen videos and it looks
pretty complex. But who needs a trailer when you have a reliable Rotax
turbo? You can fly to any location and rent a car when you get there.
You do need a hangar or a rental space to keep it. You wouldn't want to
rig it from a trailer too often.

I've helped rig and fly an ASH-30 mi and it was quite an ordeal using
all those tools and equipment to get it out of the trailer and moved and
lifted into position. It flies about the same as the Stemme. Heavy and
difficult at first and, with a bit of practice, well mannered and easy
to fly.

On 10/31/2016 2:21 PM, JS wrote:
On Monday, October 31, 2016 at 12:06:03 PM UTC-7, Duster wrote:
Thanks for the detailed comments . There are several considerations still on the table (I have 500hrs including several hours in a Duo-Discus). My ideal motorized glider: 2-seater, easy to assemble, good trailer, dependable FES or non-pyloned powerplant, electric self-launcher (would settle for sustainer), good maneuverability. Trading-off on some features (other than my wife), the Stemme, Arcus M/T and Pipistrel Taurus electric both seem to come pretty close. I might consider a Stemme, but there doesn't seem to be many used VT's (better climb v S10), and as Dan mentioned, it doesn't maneuver like a 15m. Those are both out of my price range new. Other than Dave, there wasn't much discussion about sustainers. The numbers seem a bit tedious to find, so in general what is the weight penalty between self-launchers and sustainers? Reliability the same? Faster deployment? Yes, I would consider a single-place which would give more options. The newer electrics are compelling, but one might be waiting awhile to grab one. Aside from the deployment time, do they have a weight advantage as well (including Li batteries)? Dave's presentation included reference to a 30% incidence of engine failure (2-stroke?). Electrics must be an improvement over that, presumably. I have read Eric Greenwell's excellent articles at the ASA. https://groups.yahoo.com/neo/groups/ASA-NewsGroup/info
Thanks again,
Mike
Good thoughts.
How easy is it to put a Stemme in the trailer? Most of them don't have trailers, and the enormous Cobra trailer includes some complicated bits.
Agree with Andreas' comments re ASH25Mi, etc. Hope to fly a 32 this week.
The 25 feels just like any of the others in the AS line after a short while.
The N4DM is also easy to fly but I have not rigged one and personally don't care for two-stroke engines in aircraft.
Mike, in the "you only live once" spirit... Go for the Arcus JET!
Jim

--
Dan, 5J

On Saturday, October 29, 2016 at 4:17:47 PM UTC-4, Duster wrote:
Retired now and looking to purchase a motorized glider; weighing the pros and cons of self-launchers v sustainers. Two-placer is a priority, as I would like to take my wife. Single place acceptable as long as I can keep her happy sightseeing. We plan on extensive travelling, some to both established and unestablished (i.e., w/o tugs avail) soaring areas (esp. ridge/mountain/wave). Is the weight penalty the chief difference? Engine reliability? Maintenance? Minimum 18m? Some of you may recommend getting some first-hand experience at a commercial operation; where would that be?

Any feedback appreciated, even if just to eliminate models to stay away from.
Mike

There was a remark about the unreliability of two stroke engines
( most commonly Rotax).
I have flown a PIK 20E for 7 years; while there have been a number of issues with peripherals, once the engine is raised ( and you are flying) the Rotax 501 has always started without trouble, just
a touch of choke. Full power within a minute.

John F, old no longer bold!

I'd agree that the various Rotax two-stroke found in the
Pik20E, DG400, DG800A are (generally) reliable.
I co-owned a DG400 for many years; nothing engine related
ever failed. In all those years it failed to start just once when
the pilot forgot to turn on the ignition. Hard to blame Rotax for
this!

I have also owned a DG808C with the Solo two-stroke. A brief
internet search will tell you all you need to know about this
two-stroke. Oddly the different Solo in many "turbo" gliders
seems to be very reliable.

As Dave Nadler says of motor gliders: "these are not Toyotas".
It would be so nice to have a self-launch with an engine
engineered by Honda.

On Tuesday, November 1, 2016 at 4:15:04 PM UTC-4, Dave Walsh wrote:
As Dave Nadler says of motor gliders: "these are not Toyotas".
It would be so nice to have a self-launch with an engine
engineered by Honda.

I don't think a Honda engine would improve the situation.
In my limited gas-powered motor-glider experience, the inflight
problems I can remember off the top of my head we
- fuel system contamination downstream of the filters blocking carbs
- fuel leaks
- starter switch failure
- intermittent ignition (cable harness problem)
- pylon limit switch failure (can't retract)
- prop brake failure (can't retract)
- prop brake safety-interlock switch failure (can't start)
- extension spindle-drive failure
- mechanic refilled radiator with undiluted anti-freeze (immediate overheat)
I'm sure there were a few others I forgot.

Anyway, in no case did I have a problem with the core engine;
all this stuff was glider-manufacturer or mechanic induced.
I've been quite lucky and haven't had failures lots of my friends
have endured such as drive-belts, fuel lines, starter motors,
exhaust system cracking, etc.

Some of the older two-strokes were more troublesome but the
Solos I've had have been solid.

The ArcusM system has been great!

Hope that helps clarify,
Best Regards, Dave