Front Electric Sustainer

Luka, can it be installed on certified gliders? Can it be installed on a 27?

Ramy

One of those 17's that the Lituanian team flew at Uvalde is now with it's new owner in my club. He's tested the motor a couple of times but hasn't really needed it yet (We started getting decent soaring conditions on the weekends for the first time this season right after he got the glider!). It seems an impressive installation, there's only a couple of things I think would improve it:

1: The blades pretty much float free when they're not turning. I assume this is to prevent the blades from touching the fuselage unless completely stopped (of course centrifugal force pulls them clear the moment they start turning and airflow folds them against the nose when completely stopped). I can see a possibility of someone walking around the nose of the glider when it's parked catching a blade on their leg as it's hanging a foot clear of the fuselage and potentially damaging the blade. I don't know if this is worth correcting as it would require a fair bit of complication of the system to hold the blades tight to the fuselage when not turning but also move them clear of the fuselage before they start turning.

2: An automatic system to stop the blades in the 3 and 9 o'clock position whenever the motor is stopped. The owner has found that it's a little inconvenient to do this manually and when he lent the glider to another pilot to try, he used the motor a bit, landed with the blades in the 5 and 11 position, overbraked, put the nose on the ground and momentarily dragged a prop blade. Fortunately our field is fairly lush grass and no damage was done.

Dne petek, 21. september 2012 19:55:52 UTC+2 je oseba slbair napisala:
On Friday, September 21, 2012 11:22:52 AM UTC-5, wrote:

Dear Peter,







For your info actuall price for new batterie pack is about $8,000, which I think is not so high!







Regards,







Luka







Dne petek, 21. september 2012 14:00:04 UTC+2 je oseba Peter Higgs napisala:



Hi Eric, you have missed one 'Additional Cost'...















Most of the $28,000 will be the cost of the batteries, say $18,000.







These have a life-span of just a few years. So if







they need replacing after 3 years...















Thats an 'Additional Cost' of $6,000 per year.. !!















Pete















At 22:42 20 September 2012, Eric Greenwell wrote:







On 9/20/2012 2:29 PM, Limus wrote:







I was interested until I saw $28K price tag. Jeez, that's more than







what I paid for brand new all electric Nissan Leaf car.















Is your Leaf used for glider launching? If not, probably an irrelevant







observation :^)















Instead, try penciling out the numbers ($ amounts apply to my flying for







a year - 50 flights):















Additional costs:







$280 Interest cost of the $28K







$0 depreciation







$200 added insurance cost







$480 Total extra costs















Avoided costs:







$2000 Tow fees avoided by using auto tow, or low aero-tow







$1000 Retrieve costs avoided (by car, aerotow, etc)







$3000 Total avoided costs















That's a $2520 net savings/year, which is about a 9% return on the







purchase cost, so the financials look pretty good. Now add in how much







you think the intangible benefits are worth (again, numbers for my







flying):















Added value:







$150 Avoiding 3 relights







$500 Avoiding 5 landouts







$200 Being able to fly good flights in unpredictable weather







$200 Flying more aggressively







$200 Starting earlier and/or flying later







$1250 Total added value each year















Now the return is ($2520 + $1250)/$28,000 = 13%















If I owned a LAK 17, I'd be queuing up for the FES, and that's just







using it as a sustainer! If it could really work as a self-launcher, say







in low density altitude places, it would avoid more costs and provide







greater benefits.















--







Eric Greenwell - Washington State, USA (change ".netto" to ".us" to







email me)







- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what







you need to know tinyurl.com/yfs7tnz











Luka,



Is the price yoo quoted for both batteries?

Yes for both batteries of course!

Dne sobota, 22. september 2012 07:21:16 UTC+2 je oseba (neznano) napisala:
One of those 17's that the Lituanian team flew at Uvalde is now with it's new owner in my club. He's tested the motor a couple of times but hasn't really needed it yet (We started getting decent soaring conditions on the weekends for the first time this season right after he got the glider!). It seems an impressive installation, there's only a couple of things I think would improve it:



1: The blades pretty much float free when they're not turning. I assume this is to prevent the blades from touching the fuselage unless completely stopped (of course centrifugal force pulls them clear the moment they start turning and airflow folds them against the nose when completely stopped). I can see a possibility of someone walking around the nose of the glider when it's parked catching a blade on their leg as it's hanging a foot clear of the fuselage and potentially damaging the blade. I don't know if this is worth correcting as it would require a fair bit of complication of the system to hold the blades tight to the fuselage when not turning but also move them clear of the fuselage before they start turning.



2: An automatic system to stop the blades in the 3 and 9 o'clock position whenever the motor is stopped. The owner has found that it's a little inconvenient to do this manually and when he lent the glider to another pilot to try, he used the motor a bit, landed with the blades in the 5 and 11 position, overbraked, put the nose on the ground and momentarily dragged a prop blade. Fortunately our field is fairly lush grass and no damage was done.


I would like to comment this two points:
1. If propeller is in exactly horizontal position, than it is true that blade on right side want to open due to special construction of propeller holder. But if you rotate it for one step forward than both bladed stays folded..
But it is true that when is a lot of people around there is a possibility that someone catch the blade with a leg. To avoid this at Alisport found simple solution with elastic:
http://www.alisport.com/eu/images/im...t_news2_4b.JPG
We have now available similar solution with propeller blades covers connected with elestic.

2. During summer we introduced automatic prop positioning, as you can see on newest video:
http://www.youtube.com/watch?v=pTeNK...layer_embedded

It is pretty obvious that you need to land with blades in aproximately horizontal position, which is not really an issue even with random stop.

regards,

Luka

On Saturday, September 22, 2012 12:52:56 AM UTC-7, wrote:
Dne sobota, 22. september 2012 07:21:16 UTC+2 je oseba (neznano) napisala:

One of those 17's that the Lituanian team flew at Uvalde is now with it's new owner in my club. He's tested the motor a couple of times but hasn't really needed it yet (We started getting decent soaring conditions on the weekends for the first time this season right after he got the glider!). It seems an impressive installation, there's only a couple of things I think would improve it:







1: The blades pretty much float free when they're not turning. I assume this is to prevent the blades from touching the fuselage unless completely stopped (of course centrifugal force pulls them clear the moment they start turning and airflow folds them against the nose when completely stopped). I can see a possibility of someone walking around the nose of the glider when it's parked catching a blade on their leg as it's hanging a foot clear of the fuselage and potentially damaging the blade. I don't know if this is worth correcting as it would require a fair bit of complication of the system to hold the blades tight to the fuselage when not turning but also move them clear of the fuselage before they start turning.







2: An automatic system to stop the blades in the 3 and 9 o'clock position whenever the motor is stopped. The owner has found that it's a little inconvenient to do this manually and when he lent the glider to another pilot to try, he used the motor a bit, landed with the blades in the 5 and 11 position, overbraked, put the nose on the ground and momentarily dragged a prop blade. Fortunately our field is fairly lush grass and no damage was done..





I would like to comment this two points:

1. If propeller is in exactly horizontal position, than it is true that blade on right side want to open due to special construction of propeller holder. But if you rotate it for one step forward than both bladed stays folded.

But it is true that when is a lot of people around there is a possibility that someone catch the blade with a leg. To avoid this at Alisport found simple solution with elastic:

http://www.alisport.com/eu/images/im...t_news2_4b.JPG

We have now available similar solution with propeller blades covers connected with elestic.



2. During summer we introduced automatic prop positioning, as you can see on newest video:

http://www.youtube.com/watch?v=pTeNK...layer_embedded



It is pretty obvious that you need to land with blades in aproximately horizontal position, which is not really an issue even with random stop.



regards,



Luka

So what is the status with installation of FES in the US? And any plans to install in other gliders as well?

I put out feelers last year to have a group of installations done at
Moriarty, NM. The enthusiasm was, in a word, underwhelming. I received
only one reply that expressed "definitely interested" while the others
showed only minor interest.

On consideration, the $24,000 (approx) group discounted cost was just more
than people were willing to pay in this economy.

"Ramy" wrote in message
...
On Saturday, September 22, 2012 12:52:56 AM UTC-7,
wrote:
Dne sobota, 22. september 2012 07:21:16 UTC+2 je oseba (neznano) napisala:

One of those 17's that the Lituanian team flew at Uvalde is now with
it's new owner in my club. He's tested the motor a couple of times but
hasn't really needed it yet (We started getting decent soaring
conditions on the weekends for the first time this season right after he
got the glider!). It seems an impressive installation, there's only a
couple of things I think would improve it:







1: The blades pretty much float free when they're not turning. I assume
this is to prevent the blades from touching the fuselage unless
completely stopped (of course centrifugal force pulls them clear the
moment they start turning and airflow folds them against the nose when
completely stopped). I can see a possibility of someone walking around
the nose of the glider when it's parked catching a blade on their leg as
it's hanging a foot clear of the fuselage and potentially damaging the
blade. I don't know if this is worth correcting as it would require a
fair bit of complication of the system to hold the blades tight to the
fuselage when not turning but also move them clear of the fuselage
before they start turning.







2: An automatic system to stop the blades in the 3 and 9 o'clock
position whenever the motor is stopped. The owner has found that it's a
little inconvenient to do this manually and when he lent the glider to
another pilot to try, he used the motor a bit, landed with the blades in
the 5 and 11 position, overbraked, put the nose on the ground and
momentarily dragged a prop blade. Fortunately our field is fairly lush
grass and no damage was done.





I would like to comment this two points:

1. If propeller is in exactly horizontal position, than it is true that
blade on right side want to open due to special construction of propeller
holder. But if you rotate it for one step forward than both bladed stays
folded.

But it is true that when is a lot of people around there is a possibility
that someone catch the blade with a leg. To avoid this at Alisport found
simple solution with elastic:

http://www.alisport.com/eu/images/im...t_news2_4b.JPG

We have now available similar solution with propeller blades covers
connected with elestic.



2. During summer we introduced automatic prop positioning, as you can see
on newest video:

http://www.youtube.com/watch?v=pTeNK...layer_embedded



It is pretty obvious that you need to land with blades in aproximately
horizontal position, which is not really an issue even with random stop.



regards,



Luka

So what is the status with installation of FES in the US? And any plans to
install in other gliders as well?

On Tuesday, January 29, 2013 3:46:45 PM UTC-5, Dan Marotta wrote:
I put out feelers last year to have a group of installations done at
Moriarty, NM. The enthusiasm was, in a word, underwhelming.

Sentiment will change quickly when something like this escapes the lab:

http://www.technologyreview.com/news...es-the-energy/

Hmmm, what do you think it costs to keep that coal fired glider charged up Eric?

On Wednesday, January 30, 2013 6:31:57 AM UTC, Glidergeek wrote:
Hmmm, what do you think it costs to keep that coal fired glider charged up Eric?

My FES is an earlier conversion with maximum 18kw output. It lasts for just under an hour at level cruise power, so I guess at maximum it would only last say 30 minutes, therefore recharge of batteries must take about 9kwh plus a bit of loss (not much, as nothing gets very hot when recharging).

Dunno about USA, but my UK marginal cost of electricity is less than £0.1 Sterling per kwh, so say 10 kwh is less than £1 – say $1.50.

Most flights the FES is used little or none, so the average cost per flight is much less than that.

Self Launch is not an option on my FES, but I save some launch costs by usually using winch/ground tow, or low aerotow.

Using Luka’s original estimated figures for battery replacement, and $8000 for the cost, 1000 cycles would cost about $8 per flight if fully discharged every flight. For the few times I fully discharge the batteries, that is affordable.

The biggest advantages for me, however, are the convenience, the confidence in going cross-country with no need for a retrieve crew arranged, and entering a comp with no crew, etc. etc. You can see articles I wrote on Luka’s website.

Chris N