Pre-Preg

On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders.. For all the rest we just want to know how much water can we get in it.

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it.

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

On Monday, December 5, 2016 at 7:59:28 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it..

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

Aren't the light days the ones where you most need the batteries?

Aren't the light days the ones where you most need the batteries?

I was thinking of a comp. Motor only used to prevent land out and longer day. But I suppose on a rec flying day one could take out on a light day as well. I would think that flying a light day and booming day are no different other than more turns and less aggressive speed, but a lighter craft would benefit. I'm not even sure what the GP batteries weigh.

On 12/5/2016 7:59 PM, Casey wrote:
On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it.

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

Probably has more to do with allowable max weight of non-lifting parts...

Luke Szczepaniak

On Monday, December 5, 2016 at 7:59:28 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it..

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

Putting the batteries in the wings reduces the weight of non lifting parts which means the wing spars and root area don't have to be made as heavy.
UH

On Tuesday, December 6, 2016 at 6:15:46 PM UTC+1, wrote:
On Monday, December 5, 2016 at 7:59:28 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it.

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

Putting the batteries in the wings reduces the weight of non lifting parts which means the wing spars and root area don't have to be made as heavy.
UH

And this is exactly why retrofitting an older glider to FES is impossible. With an max weight of non lifting part typically in the range of 230-250kg is it not enough marginal to put in an extra weight of 40-50kg for motor, electronics and battery in the fuselage unless you are a really light weight pilot.
I have asked the FES guys several times if it would be possible to get batteries suitable for wing installation and the answer is no.

On Wednesday, December 7, 2016 at 1:49:59 AM UTC-5, Per Carlin wrote:
On Tuesday, December 6, 2016 at 6:15:46 PM UTC+1, wrote:
On Monday, December 5, 2016 at 7:59:28 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 4:58:14 PM UTC-5, Casey wrote:
On Monday, December 5, 2016 at 2:23:59 PM UTC-5, Jonathan St. Cloud wrote:
For the guys with an engine weight does make a difference. Imagine if the 100 pounds of engine and fuel were offset by construction methods that lowered the empty weight of the glider by even 50-70 pounds. YOu would functionally have the same wing loading range as a pure glider.

Just saying.
On Thursday, December 1, 2016 at 4:09:14 PM UTC-8, wrote:
4 Pretty much nobody cares much about weight, except the little gliders. For all the rest we just want to know how much water can we get in it.

Different building methods in same factory brings several issues I could think of.
Cost of buying and storing different materials, cost of process, possible mistakes in manufacturing, return on investment, different flying characteristics. Just throwing this out there.

Maybe this is why GP decided to put the batteries in the wings. Removal for light days without changing CG. All other FES gliders have batteries behind cockpit and have to fly with batteries.

Putting the batteries in the wings reduces the weight of non lifting parts which means the wing spars and root area don't have to be made as heavy.
UH

And this is exactly why retrofitting an older glider to FES is impossible.. With an max weight of non lifting part typically in the range of 230-250kg is it not enough marginal to put in an extra weight of 40-50kg for motor, electronics and battery in the fuselage unless you are a really light weight pilot.
I have asked the FES guys several times if it would be possible to get batteries suitable for wing installation and the answer is no.

nothing is impossible.

On Wednesday, 7 December 2016 17:49:59 UTC+11, Per Carlin wrote:
And this is exactly why retrofitting an older glider to FES is impossible.. With an max weight of non lifting part typically in the range of 230-250kg is it not enough marginal to put in an extra weight of 40-50kg for motor, electronics and battery in the fuselage unless you are a really light weight pilot.


Not really a problem. Look at the old TOP installs on LS3s and 4s. An AD was issued that increased max weight of non-lifting parts. The tradeoff was a reducing in Vne and other airspeeds. So long as you stayed within CofG limits, then tradeoffs of weight for speed can always be done.

On Thursday, December 8, 2016 at 1:22:15 AM UTC+1, Justin Couch wrote:
On Wednesday, 7 December 2016 17:49:59 UTC+11, Per Carlin wrote:
And this is exactly why retrofitting an older glider to FES is impossible. With an max weight of non lifting part typically in the range of 230-250kg is it not enough marginal to put in an extra weight of 40-50kg for motor, electronics and battery in the fuselage unless you are a really light weight pilot.


Not really a problem. Look at the old TOP installs on LS3s and 4s. An AD was issued that increased max weight of non-lifting parts. The tradeoff was a reducing in Vne and other airspeeds. So long as you stayed within CofG limits, then tradeoffs of weight for speed can always be done.

Well, for us Europeans that fly certified gliders is this not easy. The Type Certificate Holder has to release an AD and for older gliders is this not likley, not unless that you pay for it.