Which sustainer system would you chose for your sailplane?

Dne torek, 25. september 2012 18:00:15 UTC+2 je oseba Eric Greenwell napisala:
On 9/25/2012 7:21 AM, Tim Mara wrote:

For performance, low weight, LOW drag, simplicity and safety. JET!

More manufacturers are developing or exploring Jet sustainers. Quite simply

the lack of moving parts, the very low weight to power output and when

properly configured to have the computer take the pilot out of decision

making of the actual operation of the engine the reliability of operation

make the Jet the best possible solution. The HpH 304 Jet doesn't require

massive, heavy and possibly hazardous batteries, doesn't require start-up

and operation or typical reciprocating engines, no priming, no chocking,

decompressing or diving to windmill and engine to start, no high parasitic

drag (the jet engine expended has actually less drag than the landing gear

down), no wind milling propellers, and short time from switch on the switch

off and stored, literally seconds to start so even at low altitudes can be

operational in seconds and without the high drag of a propeller is a non

issue when it might be necessary to glide the extra distance to make a safe

landing with an extended powerplant.

The Jet does have to be engineered right from the start and have systems

that are completely monitored and controlled by a computer system to take

the operator error possibility away and this is what has likely delayed the

release of the Jet sustainers from most manufacturers. Having flown just

about al types from simple 2 cycle ultra-lites to small corporate Jet

aircraft I can see potential issues with operators not fully trained in Jet

engine operation without the development of a computer based system to

control the operation of the jet engine. With the HpH system the controller

monitors all aspects of the engine from start-up to engine cool down and

stowage, it is simply refined ...

regards



Tim makes some excellent points for the jet sustainer, but every one of

them also applies to the FES. Sure, it's got those "possibly hazardous

batteries", but it does not have those "possibly hazardous 8 gallons of

fuel".



This illustrates the problem with the current voting choices, offered

without any description of each systems attributes. Even a dealer does

not tell us the important differences between two of the three choices,

so how can the average "voter" make an informed choice?



--

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

email me)


I will write here just a few attributes of the FES which I think are the most important:

-reliable start, full power available in 1s, switching off also very quick
-no smell in cockpit, no oil on fuselage
-small noise outside and inside of cockpit
-low vibrations
-good max climb rate about 2,5m/s at 22kW for LAK17A (depend on weigh of glider)
-very efficient system (only 4kW of power is neccesery for horizontal flight) which gives about 100km of range
-big advantage is that 12V power is available from main baterie pack, (DC/DC converter) so you have finally enough power for Radio, Transponder, PDA, Vario etc, acctually for the whole flying season
-all 12V Pb batteries can be removed (this mean usually minus 5kg)
-only about 50kg of additional weigh - 5kg of Pb= 45kg
-no change of drag or CG position during engine run
-according Idaflieg test results, drag of propeller blades is really minimal (official results published in winter)
-very chaep charging of batteries, outside of glider
-virtually maintenance-free
-price in range of Solo sustainers

Articles about FES:
http://www.front-electric-sustainer.com/articles.php

Very good article about recent JETs:
http://www.psr-jet-system.com/___010...gelfliegen.pdf

There is not much about Solo sustainers but here is one:
http://www.trb.8m.com/

So now is up to you to take some time to read and decide which one you would choose!

Regards,

Luka

I will write here just a few attributes of the FES which I think are the most important:



-reliable start, full power available in 1s, switching off also very quick

-no smell in cockpit, no oil on fuselage

-small noise outside and inside of cockpit

-low vibrations

-good max climb rate about 2,5m/s at 22kW for LAK17A (depend on weigh of glider)

-very efficient system (only 4kW of power is neccesery for horizontal flight) which gives about 100km of range

-big advantage is that 12V power is available from main baterie pack, (DC/DC converter) so you have finally enough power for Radio, Transponder, PDA, Vario etc, acctually for the whole flying season

-all 12V Pb batteries can be removed (this mean usually minus 5kg)

-only about 50kg of additional weigh - 5kg of Pb= 45kg

-no change of drag or CG position during engine run

-according Idaflieg test results, drag of propeller blades is really minimal (official results published in winter)

-very chaep charging of batteries, outside of glider

-virtually maintenance-free

-price in range of Solo sustainers



As there was a lot of votes today for JET (I think good article on link above helps) I think I need to lighten some more advantages of FES:

-Light gliders like Silent, AS13.5, Apis becomes with FES real selflaunchers with comparable or even better climb rates than if equiped with combustion retractable engines.

-Even when FES is installed on 18m glider, max climb rate is much better than it is achived with JET or Solo.

-As it is slower than JET you do not pass thermals too quickly, but you can do some turns to center (under power or even without, at normal thermaling speeds) and preserve energy. Actually is it suprising how much energy is even in weak thermals.

-You can use it in mountains, on the ridge to help you climb above the peaks. Even that you have motor you still feel it as soaring, so not bad feling...

-FES is possible to use even in horizontal flight trough (not too heavy) rain (ventlation is prefared to be closed) without fear to damage proppeller blades up to about 3500 RPM.

-Only at FES start is instant, so it can save you out of unladable valleys.

Regards,

Luka

For me electrical sustainer in a glider is the perfect solution. It links in to the spirit of the sport, beter than a turbine. But the propellor on the nose feels slightly off.... Especially when you consider the bugwipergarages becoming standard on the topsailplanes. We are spending more and more on reducing drag. Then this minor addition feels going against the flow. Why not a small pilon whit this nice foldable propellor you have engineered? Or am I the only one who has this uncomfortable feeling?

Secondly adding 45 kg to the non- lifting parts is a bit of a stretch. I contacted a manufacturer who was very kind to talk more than 30 minutes on the subject. But changing this limit on existing planes seems very far fetched. Any news in this area?

Marco

On Sep 26, 6:06*pm, wrote:
For me electrical sustainer in a glider is the perfect solution. It links in to the spirit of the sport, beter than a turbine. But the propellor on the nose feels slightly off.... Especially when you consider the bugwipergarages becoming standard on the topsailplanes. We are spending more and more on reducing drag. Then this minor addition feels going against the flow. Why not a small pilon whit this nice foldable propellor you have engineered? Or am I the only one who has this uncomfortable feeling?

Secondly adding 45 kg to the non- lifting parts is a bit of a stretch. I contacted a manufacturer who was very kind to talk more than 30 minutes on the subject. But changing this limit on existing planes seems very far fetched. Any news in this area?

Marco

I also have an issue with modification to the front of the fuselage
where the tow hook is (at least in my glider) and another point is
that this is an important area not to be tempered with in crash
resistant cockpits. I have no problems with the added weight due to my
good eating habits .

On Thursday, 27 September 2012 00:06:31 UTC+2, wrote:
For me electrical sustainer in a glider is the perfect solution. It links in to the spirit of the sport, beter than a turbine. But the propellor on the nose feels slightly off.... Especially when you consider the bugwipergarages becoming standard on the topsailplanes. We are spending more and more on reducing drag. Then this minor addition feels going against the flow. Why not a small pilon whit this nice foldable propellor you have engineered? Or am I the only one who has this uncomfortable feeling?

How about FES in an EDF (electric ducted fan) configuration instead of pylon mounted FES? The EDF could be mounted in the fuselage with doors than open and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon mounted system?
Would a smaller prop size make it less efficient and impractical?
The one advantage would be the removal of most of the pitching issue associated with pylon mounted systems.

If I had the money for a self launcher or sustainer equipped glider it would be FES due to simplicity, reliability and safety.
From a safety perspective I presume a battery fire would tend to be more isolated in a crash whereas with combustible fuel you and the glider could become engulfed in flames within seconds as fuel is splashed around.
As battery and fuel cell technology advances, alternative energy storage upgrades could be a possibility without having to purchase another glider.
I don't like the smell of gasoline or jet fuel nor the complexity with things that operate at high temperatures and need to be maintained regularly. A brushless electric motor can literally run for years with a decent set of bearings. That means less hassle and maybe lower maintenance costs over the long run depending on the battery technology being used.

A sustainer option would suite me perfectly. I don't need to operate autonomously and a winch launch to 1500 feet is cheap ($4.70 USD) and preserves power for when I may need it.

On Friday, January 8, 2016 at 1:40:33 AM UTC-5, Surge wrote:
On Thursday, 27 September 2012 00:06:31 UTC+2, wrote:
For me electrical sustainer in a glider is the perfect solution. It links in to the spirit of the sport, better than a turbine. But the propeller on the nose feels slightly off.... Especially when you consider the bugwiper garages becoming standard on the top sailplanes. We are spending more and more on reducing drag. Then this minor addition feels going against the flow. Why not a small pylon with this nice foldable propeller you have engineered? Or am I the only one who has this uncomfortable feeling?

How about FES in an EDF (electric ducted fan) configuration instead of pylon mounted FES? The EDF could be mounted in the fuselage with doors than open and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon mounted system?
Would a smaller prop size make it less efficient and impractical?
The one advantage would be the removal of most of the pitching issue associated with pylon mounted systems.

If I had the money for a self launcher or sustainer equipped glider it would be FES due to simplicity, reliability and safety.
From a safety perspective I presume a battery fire would tend to be more isolated in a crash whereas with combustible fuel you and the glider could become engulfed in flames within seconds as fuel is splashed around.
As battery and fuel cell technology advances, alternative energy storage upgrades could be a possibility without having to purchase another glider.
I don't like the smell of gasoline or jet fuel nor the complexity with things that operate at high temperatures and need to be maintained regularly. A brushless electric motor can literally run for years with a decent set of bearings. That means less hassle and maybe lower maintenance costs over the long run depending on the battery technology being used.

A sustainer option would suite me perfectly. I don't need to operate autonomously and a winch launch to 1500 feet is cheap ($4.70 USD) and preserves power for when I may need it.

With retractable gear, mixers/controls, etc., not much room for a decent sized EDF. Unless of course, you want to make the fuselage larger, but that add's wetted area and reduces the performance.

At 14:52 08 January 2016, Charlie M. UH & 002 owner/pilot
wrote:
On Friday, January 8, 2016 at 1:40:33 AM UTC-5, Surge
wrote:
On Thursday, 27 September 2012 00:06:31 UTC+2,

wrot=
e:
For me electrical sustainer in a glider is the perfect
solution. It
lin=
ks in to the spirit of the sport, better than a turbine. But
the propeller
=
on the nose feels slightly off.... Especially when you
consider the
bugwipe=
r garages becoming standard on the top sailplanes. We are
spending more
and=
more on reducing drag. Then this minor addition feels
going against the
fl=
ow. Why not a small pylon with this nice foldable propeller
you have
engine=
ered? Or am I the only one who has this uncomfortable
feeling?
=20
How about FES in an EDF (electric ducted fan)
configuration instead of
py=
lon mounted FES? The EDF could be mounted in the
fuselage with doors than
o=
pen and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon
mounted system?
Would a smaller prop size make it less efficient and
impractical?
The one advantage would be the removal of most of the
pitching issue
asso=
ciated with pylon mounted systems.
=20
If I had the money for a self launcher or sustainer
equipped glider it
wo=
uld be FES due to simplicity, reliability and safety.
From a safety perspective I presume a battery fire would
tend to be more
=
isolated in a crash whereas with combustible fuel you and
the glider could
=
become engulfed in flames within seconds as fuel is
splashed around.
As battery and fuel cell technology advances, alternative
energy storage
=
upgrades could be a possibility without having to purchase
another glider.
I don't like the smell of gasoline or jet fuel nor the
complexity with
th=
ings that operate at high temperatures and need to be
maintained
regularly.=
A brushless electric motor can literally run for years with a
decent set
o=
f bearings. That means less hassle and maybe lower
maintenance costs over
t=
he long run depending on the battery technology being
used.
=20
A sustainer option would suite me perfectly. I don't need
to operate
auto=
nomously and a winch launch to 1500 feet is cheap ($4.70
USD) and
preserves=
power for when I may need it.

With retractable gear, mixers/controls, etc., not much room
for a decent
si=
zed EDF. Unless of course, you want to make the fuselage
larger, but that
a=
dd's wetted area and reduces the performance.


I'd agree with most of the above: gasoline is certainly a
hazard in a crash but Lithium batteries are not exactly "safe"
in a crash, they too can burn and the combustion products
are very hazardous. Then there's the problem of several
hundred volts DC at large...
See:
http://www.bea.aero/fr/enquetes/2012/2012.semaine.36.pd
f

On Thursday, January 7, 2016 at 10:40:33 PM UTC-8, Surge wrote:

How about FES in an EDF (electric ducted fan) configuration instead of pylon mounted FES? The EDF could be mounted in the fuselage with doors than open and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon mounted system?
Would a smaller prop size make it less efficient and impractical?
The one advantage would be the removal of most of the pitching issue associated with pylon mounted systems.


FES is by definition the front mounted ('F') variety not pylon mounted - just to nit-pick.

As to EDF, you might be able to get one big enough to climb a glider, but the efficiencies would, I suspect, be poor and electric sustainers already face a weight/range tradeoff that is marginal for many pilots. I expect the pylon-mounted sustainers with a larger prop would be the best compromise (reliable and fast deployment, minimal drag, acceptable range, low enough weight for an 18m glider to not face too much of a weight penalty. Whether it is appreciably more efficient than an FES prop would be interesting to know - my guess is they'd be a bit more efficient. FES wins for pure simplicity..

I'd rather carry batteries around than gasoline any day. Internal combustion engines (and turbines) are a recipe for lots of mechanical fiddling and maintenance in my experience.

9B

On Tuesday, January 12, 2016 at 3:16:41 PM UTC-5, Andy Blackburn wrote:
On Thursday, January 7, 2016 at 10:40:33 PM UTC-8, Surge wrote:

How about FES in an EDF (electric ducted fan) configuration instead of pylon mounted FES? The EDF could be mounted in the fuselage with doors than open and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon mounted system?
Would a smaller prop size make it less efficient and impractical?
The one advantage would be the removal of most of the pitching issue associated with pylon mounted systems.


FES is by definition the front mounted ('F') variety not pylon mounted - just to nit-pick.

As to EDF, you might be able to get one big enough to climb a glider, but the efficiencies would, I suspect, be poor and electric sustainers already face a weight/range tradeoff that is marginal for many pilots. I expect the pylon-mounted sustainers with a larger prop would be the best compromise (reliable and fast deployment, minimal drag, acceptable range, low enough weight for an 18m glider to not face too much of a weight penalty. Whether it is appreciably more efficient than an FES prop would be interesting to know - my guess is they'd be a bit more efficient. FES wins for pure simplicity.

I'd rather carry batteries around than gasoline any day. Internal combustion engines (and turbines) are a recipe for lots of mechanical fiddling and maintenance in my experience.

9B

There are plenty of retractable engine gliders that, due to geometry changes to fit the engine etc, and/or poor doors, may well have as much drag rise over a pure glider as those 2 prop blades.
The down side to front motor is that, for almost all but the light gliders, there is not a good way to get enough ground clearance for a prop that will apply the power needed for self launch.
It is a very clever concept.
UH

On Tuesday, January 12, 2016 at 1:52:08 PM UTC-8, wrote:
On Tuesday, January 12, 2016 at 3:16:41 PM UTC-5, Andy Blackburn wrote:
On Thursday, January 7, 2016 at 10:40:33 PM UTC-8, Surge wrote:

How about FES in an EDF (electric ducted fan) configuration instead of pylon mounted FES? The EDF could be mounted in the fuselage with doors than open and close for the inlet and exhaust.
Would this make any sense or be simpler than a pylon mounted system?
Would a smaller prop size make it less efficient and impractical?
The one advantage would be the removal of most of the pitching issue associated with pylon mounted systems.


FES is by definition the front mounted ('F') variety not pylon mounted - just to nit-pick.

As to EDF, you might be able to get one big enough to climb a glider, but the efficiencies would, I suspect, be poor and electric sustainers already face a weight/range tradeoff that is marginal for many pilots. I expect the pylon-mounted sustainers with a larger prop would be the best compromise (reliable and fast deployment, minimal drag, acceptable range, low enough weight for an 18m glider to not face too much of a weight penalty. Whether it is appreciably more efficient than an FES prop would be interesting to know - my guess is they'd be a bit more efficient. FES wins for pure simplicity.

I'd rather carry batteries around than gasoline any day. Internal combustion engines (and turbines) are a recipe for lots of mechanical fiddling and maintenance in my experience.

9B

There are plenty of retractable engine gliders that, due to geometry changes to fit the engine etc, and/or poor doors, may well have as much drag rise over a pure glider as those 2 prop blades.
The down side to front motor is that, for almost all but the light gliders, there is not a good way to get enough ground clearance for a prop that will apply the power needed for self launch.
It is a very clever concept.
UH

To solve the prop size problem, would there be any way to "extend" the props once the glider is off the ground a few meters? And thus turning a FES into a "FEL" or "FEM" (no good acronyms here...)? Surely there is some mechanical way to do this? Has it been or is it being considered?