Wanting to start a new glider club

On Wednesday, January 2, 2019 at 4:18:44 PM UTC-7, Frank Whiteley wrote:
On Wednesday, January 2, 2019 at 2:39:13 AM UTC-7, Frank Whiteley wrote:
On Wednesday, January 2, 2019 at 12:59:47 AM UTC-7, John Foster wrote:
On Tuesday, January 1, 2019 at 8:13:46 AM UTC-7, Martin Gregorie wrote:
On Mon, 31 Dec 2018 19:21:45 -0800, WB wrote:

There is nothing new under the sun when it comes to ground launching,
auto tow, winch, whatever. It's pretty much all been tried. Derek Piggot
wrote a book that is a great resource for learning about ground launch
in it's many forms. Unfortunately, it appears to be out of print.

ITYM "Gliding - A handbook on Soaring Flight"

Edition 7, which I have (blue cover showing a DG-800B with its motor
out), has two chapters on ground launching and is currently on offer from
Amazon for $3.60. His books may be out of print, but you can easily find
copies. Amazon even has a Derek Piggott author page.


--
Martin | martin at
Gregorie | gregorie dot org

That books looks promising. Thanks for the link.

With regard to the pulley: what diameter would it need to be? I've seen somewhere that a higher grade of UHMWPE--New England STS-12 (formerly Endura 12), recommends a sheave:rope diameter ratio of 8:1. That would mean for a 1/8" rope, one could get away with a sheave of only 1" in a pulley. Somehow that just doesn't seem like a good idea in this application though, but I don't know. So I'm asking.

If this were the case then, one could simply order these items off Amazon and be done with it:
https://www.amazon.com/Smittybilt-27...s=snatch+block
https://www.amazon.com/dp/B01I25Z5F4...v_ov_lig_dp_it

8 inches is okay, but there are other reverse pulley considerations. If you want the wheel to track the glider climb and drift, as in the old Cotswold system, a larger diameter is probably better. It was an effective 50" radius using using small rollers to reduce any stored energy in the system, which was an issue with the Essex GC system. With UHMWPE rope, you want to eliminate both stored energy and the ability for slack rope to tuck into any gaps or result in loops that might impact on the ground or equipment. Larger rope types might help with some of this, but there are always compromises of performance and price. UV resistence, abrasive resistence, fatigue (as a result of loading cycles), and ease of handling (including splicing) are all considerations.

This might be a suitable substitute for UHMWPE ropes for reverse pulley, http://www.novabraid.com/rope/oletec-12/ though they make no claims on abrasion resistance. 3/8" might be so heavy as to cause abrasive issues. This was true on the Cotswold system using solid wire. 10 gauge was heavy enough to cause excessive wear on the "memory loops" on the wire, so 13 gauge was found to give the best performance. Use of solid wire is not recommended at public use airports wherever you are because a large clear zone is needed in case of wire breaks. Many of these new ropes have negligible stretch, thus no recoil issues. Solid wire and steel wire ropes have significant recoil hazards.

Frank Whiteley

WRT Cotswold 50" diameter.

50" diameter was for a solid steel wire. The 1:8 ratio would put the sheave diameter for a 1/8" rope at 1".

On Wednesday, January 2, 2019 at 9:49:18 PM UTC-7, John Foster wrote:
On Wednesday, January 2, 2019 at 4:18:44 PM UTC-7, Frank Whiteley wrote:
On Wednesday, January 2, 2019 at 2:39:13 AM UTC-7, Frank Whiteley wrote:
On Wednesday, January 2, 2019 at 12:59:47 AM UTC-7, John Foster wrote:
On Tuesday, January 1, 2019 at 8:13:46 AM UTC-7, Martin Gregorie wrote:
On Mon, 31 Dec 2018 19:21:45 -0800, WB wrote:

There is nothing new under the sun when it comes to ground launching,
auto tow, winch, whatever. It's pretty much all been tried. Derek Piggot
wrote a book that is a great resource for learning about ground launch
in it's many forms. Unfortunately, it appears to be out of print.

On Wednesday, January 2, 2019 at 1:01:53 PM UTC-6, John Foster wrote:
On Wednesday, January 2, 2019 at 2:11:23 AM UTC-7, Frank Whiteley wrote:
On Tuesday, January 1, 2019 at 8:13:46 AM UTC-7, Martin Gregorie wrote:
On Mon, 31 Dec 2018 19:21:45 -0800, WB wrote:

There is nothing new under the sun when it comes to ground launching,
auto tow, winch, whatever. It's pretty much all been tried. Derek Piggot
wrote a book that is a great resource for learning about ground launch
in it's many forms. Unfortunately, it appears to be out of print.

ITYM "Gliding - A handbook on Soaring Flight"

Edition 7, which I have (blue cover showing a DG-800B with its motor
out), has two chapters on ground launching and is currently on offer from
Amazon for $3.60. His books may be out of print, but you can easily find
copies. Amazon even has a Derek Piggott author page.


--
Martin | martin at
Gregorie | gregorie dot org

Derek's insights on ground launching are very good. There are a number of variables that need some additional consideration. Here in Colorado summers, we can have density altitudes approaching 10,000ft at 5500MSL field elevation, which affect performance of both winches and gliders and auto tows, if used. The OP's location is at 3000MSL with slightly lower expected seasonal temperatures.

I'm not aware of any operations that have used direct or reverse-pulleys with UHMWPE ropes. 30 plus years ago, the old Enstone GC attempted to use a pulley with Parafil and the results were not successful. Could have been a design issue. Parafil worked a treat for auto tow and could be retrieved quickly for the next launch. I'm not certain UHMWPE ropes would work in those cases, however, Amsteel II is a sheathed rope, so might work in a similar role.

Direct pulley and auto tow is often done without a drogue chute so the rope will drop without much drift. A chute could result in considerable drift without any control. A drogue chute on a reverse pulley allows the end of the rope to be landed next to the pulley and it will be set up for the next launch. A rope break is the only real problem. The OP's airport has runway lights, which in my opinion makes direct pulley and auto tow not viable. There is a second airport option, very close to the mountains, which might allow easy access to ridge soaring. If the wind is enough for ridge flight, it would also maybe help with the launch heights to reach for the lift and/or return to the airport. A reverse pulley would allow for operations from both sites, though there is the problem of different run lengths. John, what was that second airport?

Frank Whiteley

The second airport is St Ignatius (52S). Elevation is about the same at about 3K ft. Runway is only 2600 ft though. It also has runway lights.

Again, the purpose of this thread is to look at (cheap) options to get a club STARTED in a rural area in a low population density state. There is not a lot of money around here. Obviously there are better ways to launch gliders, but it costs more, and I'm looking for ways to make this affordable, at least until we can achieve critical mass to make this club self-sustaining. At that point we could start looking at options to improve launch equipment. At this point we don't even have sufficient interest to generate enough capital to buy a two-seater glider, even one that is only $6000. There is interest, but not enough people to put money on the table yet. That's my challenge.

Here's how you can afford to get a club glider: Finance it with a loan with the longest term you can and that will allow you the option of paying interest only. We did that to buy our first 2 seater. Some months, we could only afford the $50 interest. However, it got us going and we ended up actually paying off the loan early. Some people will cringe at this strategy and tell you it is financial idiocy. However, with a glider club, where we typically have a lot of membership turnover,no single individual ends up paying much more with this type of financing than with just buying a glider outright. If you have enough interest to keep the glider busy, it will soon pay for itself.

On Thursday, January 3, 2019 at 4:59:36 AM UTC-8, WB wrote:
Here's how you can afford to get a club glider: Finance it with a loan with the longest term you can and that will allow you the option of paying interest only. We did that to buy our first 2 seater. Some months, we could only afford the $50 interest. However, it got us going and we ended up actually paying off the loan early. Some people will cringe at this strategy and tell you it is financial idiocy. However, with a glider club, where we typically have a lot of membership turnover,no single individual ends up paying much more with this type of financing than with just buying a glider outright. If you have enough interest to keep the glider busy, it will soon pay for itself.

Not only that, but a glider isn't a car that will depreciate to nothing in ten years. It's not even a power plane with big engine overhaul bills every 2000 hours.

Gliders have a 50+ year lifespan (especially plastic ones) and require next to no maintenance (especially plastic ones), so it's perfectly sensible to pay them off over 20 or 25 years. If the club folds before that, you'll be able to sell the glider for enough to be able to pay off the loan.

On Thursday, January 3, 2019 at 8:35:00 PM UTC-7, Bruce Hoult wrote:
On Thursday, January 3, 2019 at 4:59:36 AM UTC-8, WB wrote:
Here's how you can afford to get a club glider: Finance it with a loan with the longest term you can and that will allow you the option of paying interest only. We did that to buy our first 2 seater. Some months, we could only afford the $50 interest. However, it got us going and we ended up actually paying off the loan early. Some people will cringe at this strategy and tell you it is financial idiocy. However, with a glider club, where we typically have a lot of membership turnover,no single individual ends up paying much more with this type of financing than with just buying a glider outright. If you have enough interest to keep the glider busy, it will soon pay for itself.

Not only that, but a glider isn't a car that will depreciate to nothing in ten years. It's not even a power plane with big engine overhaul bills every 2000 hours.

Gliders have a 50+ year lifespan (especially plastic ones) and require next to no maintenance (especially plastic ones), so it's perfectly sensible to pay them off over 20 or 25 years. If the club folds before that, you'll be able to sell the glider for enough to be able to pay off the loan.

I think this is far too long.

Many clubs have multiple gliders. Some include use in the dues (aka no use charge), or have a fixed per flight fee. Both of those approaches seem to me to be a bit short sighted. I suggest that each glider in the fleet have an amortization schedule and a sinking fund (for replacement). So, say a G-103 should be fully amortized in 1000 hours of club use (or pick some other number, but be conservative). That would set a reasonable hourly cost to the member and be goal oriented and met in a reasonable time. Now, perhaps the club has 3-4 club gliders. If the club is growing, the combined sinking funds could expand the fleet within a reasonable amount of time. If the club is not growing, then upgrading the fleet would be perhaps the preferred goal. IMVHO, remaining stagnant is not a desirable path.

So, once the operating (replacement) costs have been established, then deal with the fixed costs (e.g. those costs that must be paid in order to fly; annuals, AD compliance, insurance, minor repairs, and storage). Those fixed costs establish the dues rate. There's a little wiggle room (ADs, TNs, XPNDRs, ADS-B, etc), but the sinking funds should establish the margin for growth. The dues allow the club to operate.

Tow planes are a different topic.

FWIW,

Frank Whiteley

On Thursday, January 3, 2019 at 9:51:16 PM UTC-8, Frank Whiteley wrote:
On Thursday, January 3, 2019 at 8:35:00 PM UTC-7, Bruce Hoult wrote:
On Thursday, January 3, 2019 at 4:59:36 AM UTC-8, WB wrote:
Here's how you can afford to get a club glider: Finance it with a loan with the longest term you can and that will allow you the option of paying interest only. We did that to buy our first 2 seater. Some months, we could only afford the $50 interest. However, it got us going and we ended up actually paying off the loan early. Some people will cringe at this strategy and tell you it is financial idiocy. However, with a glider club, where we typically have a lot of membership turnover,no single individual ends up paying much more with this type of financing than with just buying a glider outright. If you have enough interest to keep the glider busy, it will soon pay for itself.

Not only that, but a glider isn't a car that will depreciate to nothing in ten years. It's not even a power plane with big engine overhaul bills every 2000 hours.

Gliders have a 50+ year lifespan (especially plastic ones) and require next to no maintenance (especially plastic ones), so it's perfectly sensible to pay them off over 20 or 25 years. If the club folds before that, you'll be able to sell the glider for enough to be able to pay off the loan.

I think this is far too long.

Many clubs have multiple gliders. Some include use in the dues (aka no use charge), or have a fixed per flight fee. Both of those approaches seem to me to be a bit short sighted. I suggest that each glider in the fleet have an amortization schedule and a sinking fund (for replacement). So, say a G-103 should be fully amortized in 1000 hours of club use (or pick some other number, but be conservative). That would set a reasonable hourly cost to the member

They're not making G-103s any more, so you'd be talking about a used one, with less life remaining. Ok, so how about an ASK-21? I was unable to find a current price (neither the US distributor nor the Germany manufacturer sees fit to publish a price list that I could find) so I'm going to guess $90000 based on what they cost ten years ago. (I'd think DG1001 Club would be an even better choice, as it's more flexible, but also costs slightly more)

Amortised in 1000 hours? So you want to load a club glider with an *extra* (over an above the fixed and variables costs) $90/hour, for the first 1000 hours?

That sounds like a good way to get a club where no one will fly.

The glider is good for 12000 to 18000 hours. Why not amortise it over the first 6000 hours? That makes the loading $15/hour, which is much more reasonable.

The only training / rides / cross country glider in a small club is going to easily do 200 to 300 hours a year if the price is not offputting. So your 6000 hours to pay back the capital is going to take 20 to 30 years. If it takes you longer .. well, the glider is just going to be a low hours and more valuable glider for longer.

If you can't manage 200 to 300 hours a year (or 100, minimum) then it's going to be the fixed costs such as interest and insurance and hangarage and 90 day maintenance inspections that kill you anyway. The glider may well always be worth more than you paid for it.

Consider buying a self launching 21. More expensive but you will not
require a tug or tuggie to operate it.
Jim

What an ingenious idea!Â* I'll bet the price difference between the self
launch version and a tug would make that an attractive proposition.

On 1/4/2019 2:12 AM, Jim White wrote:
Consider buying a self launching 21. More expensive but you will not
require a tug or tuggie to operate it.
Jim


--
Dan, 5J

On Friday, January 4, 2019 at 11:57:06 AM UTC-5, Dan Marotta wrote:
What an ingenious idea!Â* I'll bet the price difference between the self
launch version and a tug would make that an attractive proposition.

On 1/4/2019 2:12 AM, Jim White wrote:
Consider buying a self launching 21. More expensive but you will not
require a tug or tuggie to operate it.
Jim


--
Dan, 5J

Perhaps start with a touring motorglider that has a towhook. Make glider pilots and tow pilots at the same time.

On Thursday, January 3, 2019 at 5:59:36 AM UTC-7, WB wrote:
On Wednesday, January 2, 2019 at 1:01:53 PM UTC-6, John Foster wrote:
On Wednesday, January 2, 2019 at 2:11:23 AM UTC-7, Frank Whiteley wrote:
On Tuesday, January 1, 2019 at 8:13:46 AM UTC-7, Martin Gregorie wrote:
On Mon, 31 Dec 2018 19:21:45 -0800, WB wrote:

There is nothing new under the sun when it comes to ground launching,
auto tow, winch, whatever. It's pretty much all been tried. Derek Piggot
wrote a book that is a great resource for learning about ground launch
in it's many forms. Unfortunately, it appears to be out of print.

ITYM "Gliding - A handbook on Soaring Flight"

Edition 7, which I have (blue cover showing a DG-800B with its motor
out), has two chapters on ground launching and is currently on offer from
Amazon for $3.60. His books may be out of print, but you can easily find
copies. Amazon even has a Derek Piggott author page.


--
Martin | martin at
Gregorie | gregorie dot org

Derek's insights on ground launching are very good. There are a number of variables that need some additional consideration. Here in Colorado summers, we can have density altitudes approaching 10,000ft at 5500MSL field elevation, which affect performance of both winches and gliders and auto tows, if used. The OP's location is at 3000MSL with slightly lower expected seasonal temperatures.

I'm not aware of any operations that have used direct or reverse-pulleys with UHMWPE ropes. 30 plus years ago, the old Enstone GC attempted to use a pulley with Parafil and the results were not successful. Could have been a design issue. Parafil worked a treat for auto tow and could be retrieved quickly for the next launch. I'm not certain UHMWPE ropes would work in those cases, however, Amsteel II is a sheathed rope, so might work in a similar role.

Direct pulley and auto tow is often done without a drogue chute so the rope will drop without much drift. A chute could result in considerable drift without any control. A drogue chute on a reverse pulley allows the end of the rope to be landed next to the pulley and it will be set up for the next launch. A rope break is the only real problem. The OP's airport has runway lights, which in my opinion makes direct pulley and auto tow not viable. There is a second airport option, very close to the mountains, which might allow easy access to ridge soaring. If the wind is enough for ridge flight, it would also maybe help with the launch heights to reach for the lift and/or return to the airport. A reverse pulley would allow for operations from both sites, though there is the problem of different run lengths.. John, what was that second airport?

Frank Whiteley

The second airport is St Ignatius (52S). Elevation is about the same at about 3K ft. Runway is only 2600 ft though. It also has runway lights.

Again, the purpose of this thread is to look at (cheap) options to get a club STARTED in a rural area in a low population density state. There is not a lot of money around here. Obviously there are better ways to launch gliders, but it costs more, and I'm looking for ways to make this affordable, at least until we can achieve critical mass to make this club self-sustaining. At that point we could start looking at options to improve launch equipment. At this point we don't even have sufficient interest to generate enough capital to buy a two-seater glider, even one that is only $6000. There is interest, but not enough people to put money on the table yet. That's my challenge.

Here's how you can afford to get a club glider: Finance it with a loan with the longest term you can and that will allow you the option of paying interest only. We did that to buy our first 2 seater. Some months, we could only afford the $50 interest. However, it got us going and we ended up actually paying off the loan early. Some people will cringe at this strategy and tell you it is financial idiocy. However, with a glider club, where we typically have a lot of membership turnover,no single individual ends up paying much more with this type of financing than with just buying a glider outright. If you have enough interest to keep the glider busy, it will soon pay for itself.

Do you have a link for where you could get this kind of a loan? I would imagine the monthly payments would depend on a lot of things, like the amount down, interest rate, and the cost of the glider. No matter how you do it, the money is going to have to come from somewhere though. It all depends on how much.