GP 14 Update and Video of Innovative Motor Deployment System for GP14 E Motorglider

I can see this glider in my future.

I see some design differences than other gliders.
1) The trailer looks to be well designed and galvanized frame. Longer lasting and saves the time and expense of painting.
2) The wing tips are not removable. Saves time rigging, expense, and weight, but wonder if its harder or if one has to be a little more careful pulling out of trailer.
3) The gear is more forward of gear doors, where most gear is almost center of gear doors. Don't know but wondering if all gliders gear hinge the same direction (forward or rearward). I think I have seen one other glider with gear forward of the doors.
4) Looks like the wings would have to be disassembled or at least pulled out some to get the batteries out. Rigging every day would not be a problem and I guess as long as they can be charged while in the wing would not be a problem. Wonder how long the batteries are and if that is the case of removing the wing completely to get the batteries out. Not sure I would want to charge the batteries while still in the wings. I've recently had a battery catch fire overnight.
5) Wonder why all the effort to have 2 cockpits. Resale may be hurt if someone has the slim and potential buyer did not like the tight fit. Wonder if the weight is the same and L/D any better on slim.
6) I like the standard BRS. I guess it is located in the pylon compartment and would exit via the pylon doors.

Cant wait to see more of it.

On Sunday, December 27, 2015 at 4:40:08 PM UTC-8, Casey Cox wrote:
I can see this glider in my future.

I see some design differences than other gliders.
1) The trailer looks to be well designed and galvanized frame. Longer lasting and saves the time and expense of painting.
2) The wing tips are not removable. Saves time rigging, expense, and weight, but wonder if its harder or if one has to be a little more careful pulling out of trailer.
3) The gear is more forward of gear doors, where most gear is almost center of gear doors. Don't know but wondering if all gliders gear hinge the same direction (forward or rearward). I think I have seen one other glider with gear forward of the doors.
4) Looks like the wings would have to be disassembled or at least pulled out some to get the batteries out. Rigging every day would not be a problem and I guess as long as they can be charged while in the wing would not be a problem. Wonder how long the batteries are and if that is the case of removing the wing completely to get the batteries out. Not sure I would want to charge the batteries while still in the wings. I've recently had a battery catch fire overnight.
5) Wonder why all the effort to have 2 cockpits. Resale may be hurt if someone has the slim and potential buyer did not like the tight fit. Wonder if the weight is the same and L/D any better on slim.
6) I like the standard BRS. I guess it is located in the pylon compartment and would exit via the pylon doors.

Cant wait to see more of it.


The glider has potential. It seems to be a smaller version of the Diana (similar wing and fuselage shapes). But it does not have the eccentricities of the Diana (no side stick, and no spars sticking out the side of the fuselage).

There does seem to be a disconnect between the advertised range/climb and the advertised weight of the batteries. Also, a more powerful optional motor seems to serve no purpose unless it either is turning the prop faster or is turning a larger prop. Otherwise, the extra power will not used.

Removable batteries in the fuselage would be a lot more convenient than having them in the wings. A leak of the water ballast could short the batteries, but at least you would have the ballistic chute if the wings catch on fire.

And/or if the prop has a different pitch.

Two obvious reasons for not putting the batteries in the fuselage:

1 - that's where the motor assembly is.

2 - Even if the batteries and motor assembly could be fitted in the aft fuselage the C of G issues would be a big problem in such a light glider. A lot of lead in the nose would be required.

On Monday, December 28, 2015 at 7:53:48 AM UTC-5, wrote:
Two obvious reasons for not putting the batteries in the fuselage:

1 - that's where the motor assembly is.

2 - Even if the batteries and motor assembly could be fitted in the aft fuselage the C of G issues would be a big problem in such a light glider. A lot of lead in the nose would be required.

The bigger issue is the mass of non lifting items. With a low mass glider this becomes a big deal. Batteries in the fuselage increase this mass, leading to need for heavier structure, primarily the spar, this making the whole glider heavier. Move the mass to the wing, somewhat outboard is better, and this problem is avoided.
Bigger motor buys takeoff margin, then throttle back to lower consumption for balance of the climb. Larger battery not really needed.
UH

On 12/27/2015 7:05 PM, wrote:
A leak of the water ballast could short the batteries, but at least you would have the ballistic chute if the wings catch on fire.

I don't think you'd want to be hanging under a parachute in a burning
aircraft... https://www.youtube.com/watch?v=BH3XTseNpw0

--
Dan, 5J

On Monday, December 28, 2015 at 5:38:01 AM UTC-8, wrote:
On Monday, December 28, 2015 at 7:53:48 AM UTC-5, wrote:
Two obvious reasons for not putting the batteries in the fuselage:

1 - that's where the motor assembly is.

2 - Even if the batteries and motor assembly could be fitted in the aft fuselage the C of G issues would be a big problem in such a light glider. A lot of lead in the nose would be required.

The bigger issue is the mass of non lifting items. With a low mass glider this becomes a big deal. Batteries in the fuselage increase this mass, leading to need for heavier structure, primarily the spar, this making the whole glider heavier. Move the mass to the wing, somewhat outboard is better, and this problem is avoided.
Bigger motor buys takeoff margin, then throttle back to lower consumption for balance of the climb. Larger battery not really needed.
UH


The glider will have 8 gallons of disposable fuselage ballast:

http://www.gpglidersusa.com/gp14/

Maybe that 30 kg of ballast is only for light pilots. If not, it appears the glider has space in the fuselage for the 20 kg of batteries, as well as no W & B or structural issues if fuselage batteries are installed in the area planned for the fuselage ballast.

On Monday, December 28, 2015 at 7:38:01 AM UTC-6, wrote:
The bigger issue is the mass of non lifting items. With a low mass glider this becomes a big deal. Batteries in the fuselage increase this mass, leading to need for heavier structure, primarily the spar, this making the whole glider heavier. Move the mass to the wing, somewhat outboard is better, and this problem is avoided.
Bigger motor buys takeoff margin, then throttle back to lower consumption for balance of the climb. Larger battery not really needed.
UH

On both counts, exactly UH ! EY

On Sunday, December 27, 2015 at 6:40:08 PM UTC-6, Casey Cox wrote:
I can see this glider in my future.

I see some design differences than other gliders.
1) The trailer looks to be well designed and galvanized frame. Longer lasting and saves the time and expense of painting.
2) The wing tips are not removable. Saves time rigging, expense, and weight, but wonder if its harder or if one has to be a little more careful pulling out of trailer.
3) The gear is more forward of gear doors, where most gear is almost center of gear doors. Don't know but wondering if all gliders gear hinge the same direction (forward or rearward). I think I have seen one other glider with gear forward of the doors.
4) Looks like the wings would have to be disassembled or at least pulled out some to get the batteries out. Rigging every day would not be a problem and I guess as long as they can be charged while in the wing would not be a problem. Wonder how long the batteries are and if that is the case of removing the wing completely to get the batteries out. Not sure I would want to charge the batteries while still in the wings. I've recently had a battery catch fire overnight.
5) Wonder why all the effort to have 2 cockpits. Resale may be hurt if someone has the slim and potential buyer did not like the tight fit. Wonder if the weight is the same and L/D any better on slim.
6) I like the standard BRS. I guess it is located in the pylon compartment and would exit via the pylon doors.

Cant wait to see more of it.

Casey

Glad to hear of your interest - we can't wait to see you in a GP 14 :-)

Some answers to your above points:
1) Trailer "Box" in the picture is shown mounted on rather "industrial/agricultural" under-body frames that were produced in Russia. If you've ever driven in Russia you would understand why the frames are built like this. Production trailers will feature the same Peszke "box" on a much more elegant and lighter underbody frame, but still featuring AlKo bits and pieces (axle, wheels, tongue, etc.)
2) Yes, this is true, the winglets are built into the wing structure to save weight. That puts the left/right wings on the opposite sides of the fuselage for rigging. But with the wings very light weight this should not be very problematic. With the clamshell open, you will be able to raise the wingtips up to allow for fuselage removal for routine maintenance and tinkering without wing removal.
4) Yes, this is the case, but other designs have had the batteries in the wings with no ill affect (knock on wood...)
5) Maximum Performance is the answer for the Slim fuselage. Slim fusleage offers very minor reduction in weight and a noticeable improvement in drag. If you are not buying your "forever" glider, then considering the standard/large fuselage for re-sale value is very smart. However, I will say that having sat in the GP 14 standard/large fuselage, it seemed quite "cavernous" around my 5'8" 170 lb. frame.
6) The non-optional/standard equipment GRS Ballistic 'Chute opens up the cockpit without the need for a parachute on the pilot. If you take a close look a the video, the pylon and GRS compartments each have their own door(s) within a larger, removable "turtle-back" that will make maintenance and inspection much easier in that entire area, including the fuselage control linkages.

If you have not already, please go to www.gpglidersusa.com and sign up for our email list for the latest details. And please get in touch with me by phone if you would like to discuss this glider further.

Best,
Tim
GP Gliders USA