Is the ASW-27B still being made?

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...?

Wallace Berry wrote, On 5/15/2013 6:18 AM:
In article ,
Eric Greenwell wrote:

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.

Apparently there was a gas-electric hybrid glider at the AERO
Friedrichshafen show, or at least a poster about one. SoaringCafe has
pictures from the show. One pic is of a diagram of an Albastar 18m
glider with internal gasoline engine driving a generator linked to a FES.

I like the idea of starting the motor before you have to commit to using
it. There is a glider with an enclosed, internal gasoline engine - the
Stemme - but it can't be started independently of propeller operation,
and the drive shaft is a difficult technical problem requiring the side
by side seating. The Albastar has a substantial engine of 65 hp, and the
use of using a generator/electric motor for power transmission to the
propeller gives it a lot of flexibility in design the Stemme did not have.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

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

Unless you have a wet start.

On Thursday, May 16, 2013 12:41:44 AM UTC+9:30, Eric Greenwell wrote:
Wallace Berry wrote, On 5/15/2013 6:18 AM:

In article ,

Eric Greenwell wrote:



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.



Apparently there was a gas-electric hybrid glider at the AERO

Friedrichshafen show, or at least a poster about one. SoaringCafe has

pictures from the show. One pic is of a diagram of an Albastar 18m

glider with internal gasoline engine driving a generator linked to a FES.



I like the idea of starting the motor before you have to commit to using

it. There is a glider with an enclosed, internal gasoline engine - the

Stemme - but it can't be started independently of propeller operation,

and the drive shaft is a difficult technical problem requiring the side

by side seating. The Albastar has a substantial engine of 65 hp, and the

use of using a generator/electric motor for power transmission to the

propeller gives it a lot of flexibility in design the Stemme did not have.



--

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

email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm

http://tinyurl.com/yb3xywl
The original LS8-t did just that - engine could be started before the prop extended.

plantain wrote, On 5/16/2013 1:52 PM:
On Thursday, May 16, 2013 12:41:44 AM UTC+9:30, Eric Greenwell wrote:


I like the idea of starting the motor before you have to commit to using

it. There is a glider with an enclosed, internal gasoline engine - the

Stemme - but it can't be started independently of propeller operation,

and the drive shaft is a difficult technical problem requiring the side

by side seating. The Albastar has a substantial engine of 65 hp, and the

use of using a generator/electric motor for power transmission to the

propeller gives it a lot of flexibility in design the Stemme did not have.



The original LS8-t did just that - engine could be started before the prop extended.

How did the exhaust get out of the glider? Was the engine fixed in
place, and only the propeller and mast went up?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl