Mini-Winch for FES

Another aspect would make such a winch not very useful: a climb from 300 ft would cut the range considerably. I know pilots with FES planes that have hard deck of 1200 ft for the activation of the engine (same as turbos with gasoline engnes) when running out of thermals. Simply because climbing is much more absorbing than flying level with a FES (at least with the current battery generation)

On Friday, March 13, 2020 at 7:20:34 PM UTC-4, wrote:
Another aspect would make such a winch not very useful: a climb from 300 ft would cut the range considerably. I know pilots with FES planes that have hard deck of 1200 ft for the activation of the engine (same as turbos with gasoline engnes) when running out of thermals. Simply because climbing is much more absorbing than flying level with a FES (at least with the current battery generation)

If there is no other tow option available, and the difference is flying or not, it becomes very useful.
UH

At 14:53 08 March 2020, wrote:
On Saturday, March 7, 2020 at 10:20:05 AM UTC-6, Emir Sherbi
wrote:
Actually, that is not the worst of the ideas. Safer than other
ideas for
sure.
Mixed with the idea of the compound pulley and truck the hole
does not
need to be too deep

As I mentioned before, anyone heard of the Wright Brothers and
their 1903
Flyer? Pretty quick acceleration to flight speed over a short
distance.

Well as it's raining: the idea of a (large) hole in the ground with
high speed wire motion around it on an active airfield doesn't seem
to have much going for it. Be an interesting 'Health & Safety'
problem. It would be a non starter in the UK - it would be full of
water by now.

On Saturday, March 14, 2020 at 9:00:06 AM UTC-4, Dave Walsh wrote:
At 14:53 08 March 2020, wrote:
On Saturday, March 7, 2020 at 10:20:05 AM UTC-6, Emir Sherbi
wrote:
Actually, that is not the worst of the ideas. Safer than other
ideas for
sure.
Mixed with the idea of the compound pulley and truck the hole
does not
need to be too deep

As I mentioned before, anyone heard of the Wright Brothers and
their 1903
Flyer? Pretty quick acceleration to flight speed over a short
distance.

Well as it's raining: the idea of a (large) hole in the ground with
high speed wire motion around it on an active airfield doesn't seem
to have much going for it. Be an interesting 'Health & Safety'
problem. It would be a non starter in the UK - it would be full of
water by now.

The idea of dropping a weight into a hole - i.e. a dried-up oil-well in Texas - was discussed ad nausea in the winchdesign forum a couple of years back. The biggest issue is the control-ability of such a setup.
Personally, I find the idea of building a small winch to launch FES-equipped gliders just off the ground only to push precious electrons through the motor to gain altitude, a pretty bad one. Use a manly winch and do a normal winch launch and keep them precious electrons on one side of the battery!

Uli
'AS'

All fine and good, Uli, but think of the height you could get by
dropping a huge weight down a 7,000' vertical shaft.Â* Then you could
have all the greenies in the area crank it back up by hand so that
there's zero carbon footprint.Â* Except for the labored breathing... :-D

On 3/14/2020 8:50 PM, AS wrote:
On Saturday, March 14, 2020 at 9:00:06 AM UTC-4, Dave Walsh wrote:
At 14:53 08 March 2020, wrote:
On Saturday, March 7, 2020 at 10:20:05 AM UTC-6, Emir Sherbi
wrote:
Actually, that is not the worst of the ideas. Safer than other
ideas for
sure.
Mixed with the idea of the compound pulley and truck the hole
does not
need to be too deep

As I mentioned before, anyone heard of the Wright Brothers and
their 1903
Flyer? Pretty quick acceleration to flight speed over a short
distance.
Well as it's raining: the idea of a (large) hole in the ground with
high speed wire motion around it on an active airfield doesn't seem
to have much going for it. Be an interesting 'Health & Safety'
problem. It would be a non starter in the UK - it would be full of
water by now.
The idea of dropping a weight into a hole - i.e. a dried-up oil-well in Texas - was discussed ad nausea in the winchdesign forum a couple of years back. The biggest issue is the control-ability of such a setup.
Personally, I find the idea of building a small winch to launch FES-equipped gliders just off the ground only to push precious electrons through the motor to gain altitude, a pretty bad one. Use a manly winch and do a normal winch launch and keep them precious electrons on one side of the battery!

Uli
'AS'

--
Dan, 5J

On Sunday, 15 March 2020 02:50:45 UTC, AS wrote:
On Saturday, March 14, 2020 at 9:00:06 AM UTC-4, Dave Walsh wrote:
At 14:53 08 March 2020, wrote:
On Saturday, March 7, 2020 at 10:20:05 AM UTC-6, Emir Sherbi
wrote:
Actually, that is not the worst of the ideas. Safer than other
ideas for
sure.
Mixed with the idea of the compound pulley and truck the hole
does not
need to be too deep

As I mentioned before, anyone heard of the Wright Brothers and
their 1903
Flyer? Pretty quick acceleration to flight speed over a short
distance.

Well as it's raining: the idea of a (large) hole in the ground with
high speed wire motion around it on an active airfield doesn't seem
to have much going for it. Be an interesting 'Health & Safety'
problem. It would be a non starter in the UK - it would be full of
water by now.

The idea of dropping a weight into a hole - i.e. a dried-up oil-well in Texas - was discussed ad nausea in the winchdesign forum a couple of years back. The biggest issue is the control-ability of such a setup.
Personally, I find the idea of building a small winch to launch FES-equipped gliders just off the ground only to push precious electrons through the motor to gain altitude, a pretty bad one. Use a manly winch and do a normal winch launch and keep them precious electrons on one side of the battery!

Uli
'AS'

To me as well, it makes more sense to use the whole winch launch. And even for longer retrieves too, drop in on and relaunch at a couple of clubs, cruise level, depending on wind could get back from 120 to 150 away.

On Sunday, 15 March 2020 16:14:24 UTC, wrote:
On Sunday, 15 March 2020 02:50:45 UTC, AS wrote:
On Saturday, March 14, 2020 at 9:00:06 AM UTC-4, Dave Walsh wrote:
At 14:53 08 March 2020, wrote:
On Saturday, March 7, 2020 at 10:20:05 AM UTC-6, Emir Sherbi
wrote:
Actually, that is not the worst of the ideas. Safer than other
ideas for
sure.
Mixed with the idea of the compound pulley and truck the hole
does not
need to be too deep

As I mentioned before, anyone heard of the Wright Brothers and
their 1903
Flyer? Pretty quick acceleration to flight speed over a short
distance.

Well as it's raining: the idea of a (large) hole in the ground with
high speed wire motion around it on an active airfield doesn't seem
to have much going for it. Be an interesting 'Health & Safety'
problem. It would be a non starter in the UK - it would be full of
water by now.

The idea of dropping a weight into a hole - i.e. a dried-up oil-well in Texas - was discussed ad nausea in the winchdesign forum a couple of years back. The biggest issue is the control-ability of such a setup.
Personally, I find the idea of building a small winch to launch FES-equipped gliders just off the ground only to push precious electrons through the motor to gain altitude, a pretty bad one. Use a manly winch and do a normal winch launch and keep them precious electrons on one side of the battery!

Uli
'AS'

To me as well, it makes more sense to use the whole winch launch. And even for longer retrieves too, drop in on and relaunch at a couple of clubs, cruise level, depending on wind could get back from 120 to 150 away.

I seem to have missed out km

On Thursday, March 5, 2020 at 1:22:48 AM UTC-5, son_of_flubber wrote:
I'd rather take my chances on something that would accelerate the glider 0-50 knots in 50 meters with the FES running from the very start of the roll. This would increase available runway ahead for launch failure and conserve a bit of battery power. Fully automated with pilot pushing the go button.


This is really the idea right here. As we increasingly embrace self-launch eGliders, I think we'll see more and more gliders operating out of small airports without the benefit of a club. Thus, what's missing in the conversation is a consideration of the CONOPS (CONcept of OPerationS) for single-person launching.

Gliders have a major limitation in requiring a team to get a single pilot airborne. Having a catapult, which terminates before the runway begins, would get the plane airborne without requiring outside help. It could be semi-permanently installed and not require setup or teardown. The energy needed to accelerate a 300kg plane to 25m/s fits in a battery the size of a tangerine.

When the planes are reported as typically using only 20% of their packs to go fly, I feel this tells us that the major risk isn't climb out, it's takeoff.

Ignoring the risk imparted by the catapult, there are several consequent risk reductions:

1) At a 10% climb grade, a catapult on a 3000' runway would allow a plane to reach 100' with 2000' of runway to spare. An engine failure suddenly becomes a very easy straight-ahead recovery. Contrast this to a more leisurely ground roll on grass which eats up 1000' and where an engine failure at 100' is a real cause for sphincter puckering.
2) For FES-style systems, the prop can be started once off the ground, eliminating the possibility of a ground strike
3) No chance of ripping the wings off the plane due to an over-exuberant winch operation
4) Reduced chance of ground-looping on roll-out, esp. in cross-wind scenarios.
5) Everything that goes wrong goes wrong at low altitude at low speeds
6) Does not impact the runway or leave anything on or near the runway

Relatedly, any kind of automated winch or autotow system requires serious thought about what to do with the launch system once the pilot flies away. A catapult doesn't have this problem since it is installed before the threshold.

I'm not saying getting the catapult right would be easy, but it definitely has a different operational spec than a winch or autotow.

I'm not saying getting the catapult right would be easy, but it definitely has a different operational spec than a winch or autotow.

Heck, let's go for altitude also! Try the Trebuchet. Judging by the altitude Monty Python got using a cow, you ought to be able to fling a 1-26 at least Silver Distance!

On Thursday, June 4, 2020 at 6:55:24 PM UTC-4, wrote:
I'm not saying getting the catapult right would be easy, but it definitely has a different operational spec than a winch or autotow.

Heck, let's go for altitude also! Try the Trebuchet. Judging by the altitude Monty Python got using a cow, you ought to be able to fling a 1-26 at least Silver Distance!

Register that glider in the Isle of Man so it can have the registration M-OOOO.