Front Electric Sustainer

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.

Limus
Lak-17AT

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

On Thursday, September 20, 2012 6:43:29 PM UTC-4, Eric Greenwell wrote:
If it could really work as a self-launcher, say
in low density altitude places...

Electric propulsion systems are barely affected by density
altitude. As density altitude increases, there will be a
small decrease in propeller efficiency, and you have to
accelerate to a higher true airspeed so take-off run
will be slightly longer. In practice there is very
little density altitude effect...

Hope that is clear,
Best Regards, Dave

On 9/20/2012 4:05 PM, Dave Nadler wrote:
On Thursday, September 20, 2012 6:43:29 PM UTC-4, Eric Greenwell wrote:
If it could really work as a self-launcher, say
in low density altitude places...

Electric propulsion systems are barely affected by density
altitude. As density altitude increases, there will be a
small decrease in propeller efficiency, and you have to
accelerate to a higher true airspeed so take-off run
will be slightly longer. In practice there is very
little density altitude effect...

Hope that is clear,
Best Regards, Dave

Well then, that makes the price seem even better! Time to send a plane
ticket to that FES installer guy and get him here! $28,000 to add
self-launch capability is really, really cheap. It cost me $30,000 to do
that on my ASH 26 E 17 years ago, so I'll bet it's double that by now.

--
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

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

On Friday, September 21, 2012 6:00:04 AM UTC-6, Peter Higgs wrote:
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



I would recommend that anyone interested in the FES to visit the FES website to be able to read up on the technology, design and performance. You can also sign up for a FES newsletter. The site is:

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

Regarding the batteries they should be good for up to 1,500 full cycles. Per the website:

"Cell manufacturer claims that at discharging with 1C rating (horizontal flight) life expectancy of batteries is around 1500 cycles. After that the battery will still have 80% of the original capacity."

If you think about it, for most flights you will never need to use the sustainer (unless you are using the sustainer for launch after an auto tow), so in a soaring season, where one is using aero tows, you may only need to start it a few times. For example, during the WGC in Uvalde, the two Lithuanian pilots flying two LAK-17B FES gliders only used the FES on 3 flights out of their total of 26 competition days.

As a result, 1,500 cycles should last you many, many years. In addition, battery technology is quickly advancing, and if one is so inclined and wants to spend the $$$, newer, more powerful batteries will undoubtedly be developed in future years and an owner can upgrade as these newer batteries become available.

Thanks,
Renny
Owner LAK-17B FES

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

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?

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.