the trend is............

wrote:
Bumper says "Pure" gliders are disabled."

I would concur, but the disability has little to do with the motor and
much to do with the pilot(s) of said machines

Yes. We are financially disabled!

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon

At 14:46 21 October 2008, Eric Greenwell wrote:

It does save me about 10 gallons
of auto fuel when I fly, because I can fly from the local airport
instead of driving to the nearest gliderport.


--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

jeez Eric, what do you drive? I get over 400 miles out of 10 gallons of
fuel in my car! But I am glad that you are saving the planet. That must be
masses of CO2 per launch saved.

Jim

On Oct 21, 11:43*am, "
wrote:
uses and he averages about 3 liters per launch over time.
Of course when I asked the Antares pilot what his fuel consumption
average was he just laughed! Some guys just don't want to contribute
to scientific study!!!

Bob

Reminds me - I need to send my plane a text message to top up the
batteries, 'cause I want to go flying later this week...
See ya, Dave "YO electric"

On Oct 21, 4:15*pm, "Bill Daniels" bildan@comcast-dot-net wrote:
snip

Your self launcher is limited to just launching you. *A winch can launch
anybody with a CG hook. *It looks likely that competitively priced electric
winches will be possible which use only around 1 KWH per launch. *That's
less than 10 cents most places.
snip

For the electricity, but the cost of launches will be more as
maintenance and depreciation will have to be covered, as might the
cost of getting a power supply to all the places the winch might be
(I've seen 4 distinct locations where I fly, with two of them having a
number of variations - we try to get a straight into-wind launch) and
also wages for clubs which have paid winch drivers.

Jim White wrote:
At 14:46 21 October 2008, Eric Greenwell wrote:

It does save me about 10 gallons
of auto fuel when I fly, because I can fly from the local airport
instead of driving to the nearest gliderport.

jeez Eric, what do you drive? I get over 400 miles out of 10 gallons of
fuel in my car! But I am glad that you are saving the planet. That must be
masses of CO2 per launch saved.

My old Dodge Grand Caravan gets about 20 mpg (@ 60 mph) when towing my
2400 pound Cobra trailer. If I really had to fly from Ephrata, the
closest place with a tow, I'd probably leave the glider there most of
the time during the season and drive up in my 2002 Camry; however, even
with it's 4 cylinder engine, it won't get 40 mpg at 60-70 mph.

I am looking forward to the plug-in hybrids coming the next year or two,
or even an electric car.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

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

wrote:
On Oct 21, 4:46 pm, Eric Greenwell wrote:
wrote:
Doesn't a winch launch use more fuel than a self-launch? And won't the
fuel he uses to commute to work eat into any savings from winch launching?
--
We average 1/2 liter of fuel per winch launch. This has been the
average over the last 10 years. We launch from a 1000 meter field and
get 350-400 meter launches.
We launch everything from K8's to Nimbus 3DT's. The consumption goes
up if you are only launching double seaters but overall 1/2 liter per
launch is the average.
That's really good! My ASH 26 E uses a little more than that for the
same launch height, but not much more. It does save me about 10 gallons
of auto fuel when I fly, because I can fly from the local airport
instead of driving to the nearest gliderport.


What is your average fuel consumption per launch? You have warmup time
and taxi time and such. I asked on of our flyers with a DG800 what he
uses and he averages about 3 liters per launch over time.

I estimate, but have never carefully measured, that I use 2 liters to
taxi about 1500 feet and launch to 2000' agl. The Wankel is more fuel
efficient than the two-strokes, so 3 liters sounds right for the DG 800.

Of course when I asked the Antares pilot what his fuel consumption
average was he just laughed! Some guys just don't want to contribute
to scientific study!

The Antares pilot I know uses far more fuel to taxi and launch than I
do, because he charges the glider with a portable, gasoline fueled
generator (at least at contests and camps - not sure what he does at
home). Ironic, eh?

I could live with that, if someone gave me an Antares.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

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

Now, now Eric.

A launch uses less than 800ml ( 1 quart) of petrol on our prehistoric inefficient Ford V8 powered winch. That is an
average over decades of use...

That gives around 1300 to 1700 feet AGL depending on wind, aircraft and skill - add some fuel for the retrieve and you
are still around 1 litre per launch with our winch (almost exclusively big heavy old two seaters). Newer multi drum
designs are a lot better.

I expect the average self launcher is using a lot more than that to get to the first thermal. Average engine time is
apparently around 5 minutes. (Schleicher figure)

Assume you have a strong SLMG say an ASH26 which claims 3.4m/s climb. You need 2.7 minutes of full power climb + run up
+ ground run + shut down to end at the same height.
The AE50R is relatively fuel efficient, (most SLMGs are two strokes) but it is still developing around 37kw for 4-5
minutes. Max power at 6900RPM uses 16 litres in 75 minutes - so five tach minutes gives you 1.06 litres.

Remarkably similar to a winch.

Just my bit of matchbox arithmetic - I assume you have actual fuel consumption numbers?

Of course the bottom line is that the fuel used in either launch mode is far exceeded by the trip to the airfield for
almost everyone, and is negligible in comparison to the work commute. My 216km round trip to the glider field uses
around 18l if I am VERY well behaved.

I find that the economy on my work commute is exceptional when I work from home.

Bruce

Eric Greenwell wrote:
Martin Gregorie wrote:
On Sun, 19 Oct 2008 08:18:10 -0700, Brad wrote:

As a bottom feeder in the economic food chain, when all gliders that are
flying are motorgliders, I'll be looking at all the pictures I took when
I used to be able to fly a non-powered sailplane. Since it will be
somewhat impossible for me to ever afford a powered sailplane.

No complaints, just an honest asessment.

Move near to a winching site and you'll have the last laugh as fuel
prices go sky high.

Doesn't a winch launch use more fuel than a self-launch? And won't the
fuel he uses to commute to work eat into any savings from winch launching?

On Oct 21, 1:36*pm, Eric Greenwell wrote:
The Antares pilot I know uses far more fuel to taxi and launch than I
do, because he charges the glider with a portable, gasoline fueled
generator (at least at contests and camps - not sure what he does at
home). Ironic, eh?

I could live with that, if someone gave me an Antares.

At the two nationals I flew at this year, I was able to find a parking
space near an outlet and didn't use the generator... At home it is
plugged in. The generator is only for especially rustic sites...
See ya, Dave "YO electric"

"Cats" wrote in message
...
On Oct 21, 4:15 pm, "Bill Daniels" bildan@comcast-dot-net wrote:
snip

Your self launcher is limited to just launching you. A winch can launch
anybody with a CG hook. It looks likely that competitively priced electric
winches will be possible which use only around 1 KWH per launch. That's
less than 10 cents most places.
snip

For the electricity, but the cost of launches will be more as
maintenance and depreciation will have to be covered,
_______
Of course. But all inclusive maintenance is not likely to exceed $2/launch.
Still very cheap.
_______
as might the cost of getting a power supply to all the places the winch
might be
(I've seen 4 distinct locations where I fly, with two of them having a
number of variations - we try to get a straight into-wind launch)
_______
Most proposals include a ~20KW genset to charge up a high power
density(LiFePo4 or ultracapacitors) battery pack between launches. The
battery pack acts as a buffer to store enough energy for 40 seconds or so of
maximum power. Think hybrid automobiles.

Of course, if you can connect with the grid, the genset wouldn't be used.
The grid connection needen't be extremely robust since it only needs to
supply average power over multiple launches, not peak power. The grid
connection would be determined by the launch rate you want.
_______
and also wages for clubs which have paid winch drivers.
_______

These are likely to be extremely automated winches so I wouldn't pay a winch
driver very much - if anything. Professional winch drivers are likely to go
extinct the way elevator (Lift?) operators did.

On Oct 19, 4:56*pm, Martin Gregorie
wrote:

Move near to a winching site and you'll have the last laugh as fuel
prices go sky high.

I know places where you can winch straight into wave....

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |

I would have to move at least 1000 miles, and probably across the
Atlantic ocean to get near a winch launch site. If gas gets stupid
expensive, I'll have to switch to sailboats, cause I live right on the
water.

Todd Smith
3S