Is the ASW-27B still being made?

On Saturday, May 11, 2013 10:23:05 AM UTC-5, Rick Lake wrote:
I've seen conflicting reports, some of which say it's been replaced in production by the ASG-29.



Thanks

Thanks for all the opinions and advice guys!

Rick Lake

On Sunday, May 12, 2013 6:47:37 PM UTC-6, wrote:
Thanks for all the opinions and advice guys!



Rick Lake
Rick, one last thing to follow on to what TK said. Last year I was helping a buddy with some glide testing and we flew a 27 and a 29 in the 15M config side by side. First, I was surprised when we had them next to each other on the ramp you could see a obvious difference in the wings. We ballasted the 27 to the same wing loading as the 29 and towed to 10K and the planes were glued together throughout the entire speed range. This was at a light wing loading. If you can't get the factory to build you a 27 there are plenty of clean used ones around.

On 5/12/2013 6:25 PM, SP wrote:
On Sunday, May 12, 2013 6:47:37 PM UTC-6, wrote:
Thanks for all the opinions and advice guys!



Rick Lake
Rick, one last thing to follow on to what TK said. Last year I was
helping a buddy with some glide testing and we flew a 27 and a 29 in
the 15M config side by side. First, I was surprised when we had them
next to each other on the ramp you could see a obvious difference in
the wings. We ballasted the 27 to the same wing loading as the 29 and
towed to 10K and the planes were glued together throughout the entire
speed range. This was at a light wing loading. If you can't get the
factory to build you a 27 there are plenty of clean used ones
around.

If Rick has the slightest interest in a motorglider, I suggest the used
route. I think the next few years will see some very interesting
motorgliders based on front mounted electric motors (and lighter, more
powerful batteries), plus jet powered self-launching and sustainer
equipped gliders.

For example, Windward Performance is now building at least two jet
powered DuckHawks (aka "JetHawk"). I'm really looking forward to
learning the performance details.

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

I think the next few years will see some very interesting
motorgliders based on front mounted electric motors (and lighter, more
powerful batteries), plus jet powered self-launching and sustainer
equipped gliders.


For example, Windward Performance is now building at least two jet
powered DuckHawks (aka "JetHawk"). I'm really looking forward to
learning the performance details.


A bit off topic by now, but what the heck...

It strikes me the right answer for sailplanes is a front electric sustainer powered by a very small battery and fuel cell.

Gliders need light weight. Batteries are all sorts of things but they are not light weight.

Is this to appeal to "green?" Listening to the Antares owners recharge their huge batteries by running loud gas powered generators all night makes a mockery of green. Besides which, the fuel for the motorhome dwarfs what we use for gasoline sustainers.

Gas engines are heavy, and complex to start and operate.

Jet engines are cool, light, and start easily (I gather), but inefficient so you have to carry a lot of fuel. The duckhawk is already suspiciously high wingloading. To say nothing of the FAA's attitude towards experimental jets.

The FES starts instantly, has little drag when extended so needs less power, and if powered by a fuel cell would be really light too.

If fuel cells are impractical, why not a small motor recharging the battery? Then you could have a much smaller battery and motor. You're low, press the switch. The battery fires up and gives you instant power. In a few seconds the motor starts too and you use both battery and electricity from motor and generator for a fast 2000' climb. When the battery is out, engine-generator-motor to sustain or climb slowly. When you shut down, the motor keeps running to recharge the battery. If the motor didnt' start you'd have say 1000' of climb and a few minutes of battery to sort things out for your off field landing.

The energy density of gasoline is hard to beat.

John Cochrane
Still motorless

On Tuesday, May 14, 2013 12:35:52 PM UTC-4, wrote:
I think the next few years will see some very interesting

motorgliders based on front mounted electric motors (and lighter, more

powerful batteries), plus jet powered self-launching and sustainer

equipped gliders.





For example, Windward Performance is now building at least two jet

powered DuckHawks (aka "JetHawk"). I'm really looking forward to

learning the performance details.





A bit off topic by now, but what the heck...



It strikes me the right answer for sailplanes is a front electric sustainer powered by a very small battery and fuel cell.



Gliders need light weight. Batteries are all sorts of things but they are not light weight.



Is this to appeal to "green?" Listening to the Antares owners recharge their huge batteries by running loud gas powered generators all night makes a mockery of green. Besides which, the fuel for the motorhome dwarfs what we use for gasoline sustainers.



Gas engines are heavy, and complex to start and operate.



Jet engines are cool, light, and start easily (I gather), but inefficient so you have to carry a lot of fuel. The duckhawk is already suspiciously high wingloading. To say nothing of the FAA's attitude towards experimental jets.



The FES starts instantly, has little drag when extended so needs less power, and if powered by a fuel cell would be really light too.



If fuel cells are impractical, why not a small motor recharging the battery? Then you could have a much smaller battery and motor. You're low, press the switch. The battery fires up and gives you instant power. In a few seconds the motor starts too and you use both battery and electricity from motor and generator for a fast 2000' climb. When the battery is out, engine-generator-motor to sustain or climb slowly. When you shut down, the motor keeps running to recharge the battery. If the motor didnt' start you'd have say 1000' of climb and a few minutes of battery to sort things out for your off field landing.



The energy density of gasoline is hard to beat.



John Cochrane

Still motorless

Cool, the flying Volt! :-)

On 5/14/2013 9:35 AM, wrote:

The FES starts instantly, has little drag when extended so needs less
power, and if powered by a fuel cell would be really light too.

If fuel cells are impractical, why not a small motor recharging the
battery? Then you could have a much smaller battery and motor. You're
low, press the switch. The battery fires up and gives you instant
power. In a few seconds the motor starts too and you use both battery
and electricity from motor and generator for a fast 2000' climb. When
the battery is out, engine-generator-motor to sustain or climb
slowly. When you shut down, the motor keeps running to recharge the
battery. If the motor didnt' start you'd have say 1000' of climb and
a few minutes of battery to sort things out for your off field
landing.

The energy density of gasoline is hard to beat.

The FES is very attractive, for sure. Windward is also working on one of
those for the SparrowHawk R. They call it "front mounted tractor", since
FES is taken.

I don't know enough about fuel cells to be sure, but I suspect one with
enough power for a good climb of 5 knots might be very expensive. Maybe
have a Li battery for the 2000' of climb, and recharge slowly from a
small fuel cell.

I've wondered if a gas-electric hybrid would be practical. A gas motor
powerful enough to supply half the energy of a 2000' climb at 500 fpm
would be about 20 hp, a fair sized motor. So again, maybe the solution
is a big enough Li battery to do the whole 2000', then use 4 hp motor to
recharge the battery over the next 30 minutes or so.

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

At 16:35 14 May 2013, wrote:

It strikes me the right answer for sailplanes is a front electric
sustainer=
powered by a very small battery and fuel cell.=20

I like your thinking John. Fuel cells also produce water (useful for
hydration) and heat (useful for socks). If you choose a direct ethanol
version you would also have a ready supply of hooch for when you eventually
land out and need a drink!

Jim

On Tuesday, May 14, 2013 10:35:52 AM UTC-6, wrote:

It strikes me the right answer for sailplanes is a front electric sustainer powered by a very small battery and fuel cell.

Gliders need light weight. Batteries are all sorts of things but they are not light weight.

It depends on the energy density of the chemistry (in Mega Joules/kg.)
Lead-acid: .17 mJ/kg.
Lithium Ion: 0.72-0.875 mJ/kg
lithium-Air: 9.0 mJ/kg.
Hydrogen-air fuel cell: 97 mJ/kg
IC engine w/fuel: Typically 9 mJ/kg

Lithium-air looks promising. Hydrogen-air fuel cells have proven to have long endurance in aircraft propulsion systems. Lithium batteries can deliver a huge surge of power for takeoff. A "range-extender" fuel cell/lithium battery hybrid looks interesting for electric vehicles but in a glider...?

Jet engines are cool, light, and start easily (I gather)

Unless you have a wet start.