Twin boom pusher electric sailplane

[Connexxion]

Look at what I found today:

http://www.rchobbyshop.de/shop/detail.php?id=406

A twin boom pusher electric sailplane.

You don't find them easy on the internet.

[Gary Mortimer]

That looks just the job, now to find somebody that has flown one.

I can't find it in the Jamara site http://www.jamara-modelltechnik.de/index.php/cat/c117_Electric-Glider.html maybe its been discontinued.

G

But wait, I found it on the Flair site http://www.flairmodels.co.uk/Aircraft/Jamara/easy_riser.htm

Very interesting, would now really like to hear if anyone has flown one.

[Connexxion]

I think it's discontinued,since the site says :

"Hersteller: Exklusiv nur noch im RCHobbyshop"

Which means:"Manufacturer: Exclusive only in RcHobbyshop"

Damn,it looks like just what we're looking for.

[Airboatflyingshp]

It was......pester them you might find some old stock failing that there is a free plan for very simillar design called Big brother or Xpo4 .... designed by a French man it shows up in glow and elec versions PM me if you want either....but Ive posted this before and close ups of the Jamara Easy Riser.......... The other name to look for is the Russian M55 Mystic or M17 Geophysica :cool: .There is a PSS version out there and several one offs.

[Gary Mortimer]

Just spotted this, not quite twin boom but an interesting looking aircraft.

http://www.hobby-lobby.com/aeromaster.htm

[workshop]

Yeah... I've been looking at that one HARD... Thinking of building battery compartments in the wings and using that huge canopy area for electronics...

:D

[Gary Mortimer]

Great plan airshipflyingboat !! Thanks for posting it.

G

[Airboatflyingshp]

Gary I remembered that version doesn't show the ribs try this dxf version for that, I will try to find the other versio but it might be a cad file. Fritz Decat is the person I sorted this out for previously :)
You may need a free view print prog try Volvo view or A N other :)

[Connexxion]

Seems aeronaut's design:

http://www.aero-naut.net/138.html

[Mark Harris]

Interesting design.. wonder how much they cost.

[Mark Harris]

I'm going to get a set of plans for the big brother printed, in current size and probably 25% larger. Would anyone be interested in having a set printed for them at the same time? Postage would be approx $10USD to anywhere in the world (Australia Post charges one flat rate for parcels under 250g).

[Connexxion]

Hi Mark,

Very kind of you to offer us a copy.

What does it look like?Do you have a picture of the plane?

Connexxion

[Airboatflyingshp]

Good on you Mark ................I assume your using the CAD file where all the ribs are visible, its the pale yellow or greys that drop out on the PDF's.
At +25% is going to be an impressive kite .......... the square wing area ratio will be so floaty..........or your payload can increase.
The simple Pod structure you can always add more depth/width space to the pod for payload space modern small servos ..a folding prop set up and gearing will make the most of any battery power ..one of the good things about the Easy riser was its endurance on a cheap geared S480 can motor ..a bit of skill and luck and this sort of machine can Roller coast for hours.

For anyone contemplating a ICE version and wanting long endurance quietness and economy you could do far worse than contemplate a RC throttling Diesel from the likes of PAW or a Diesel head conversion of a Glow motor....... just an idea.

I look forward to seeing this one.

[Mark Harris]

Airboatflyingship,
Yes i plan on printing the cad version. I'm going to call a few friends who work at mining companies and see if they can possibly print it on a plotter there for free. Failing that i'd have to go to a printing company. I hope the cost of printing it wont be too excessive though.

Of course i'd print the CAD version :) It seems like a really good looking plane. Have you found any pictures of it?

The standard version has a 60mm wide fuselage at its widest point, and is approx 533mm long. You'd probably want an e-flite power 25 or power 32 brushless outrunner motor on this thing.

25% scaled up will be 2875mm wing span. Thats pretty big hehe. Put a big brushless outrunner and a big lipo in there and you'll never need to bring the bird down if you get thermals like i do in summer!

Once i finish my UAV i plan to start directly onto making this.

[Mark Harris]

heh.. the printing place i was looking at cant do it for another month.. their plotter is broken hehe. Lucky i wont be able to do anything with it for about a month ;)

[Airboatflyingshp]

The design is French in orogin and has been around for quite a while so a crude dd s6oo or much better 3.5 -4 :1 geared S600 was what it was built for, xpr is just the glow version.
Find a folding prop that can work as a pusher and is about that equiv .......master airscrew, Aeronuat, Cam match it to your motor set up ........... gearing an outrunner offends some but MEC and a lot of others have found it can be very effective if turning large props.

[Mark Harris]

The plans say 8x4.5.. not really that big :)

[Airboatflyingshp]

Thats a S600 Direct drive prop - forget it check the gap between the booms and see how big you can go theoretically ....compare that with the Easy riser or any other Glider of this size/wt but I would say you should go for a geared brushed motor swinging a folding 12x8 master Airscrew as a minimum they do a larger version for deeper gearing, larger motors. Look at the Aeronaut three bladed sets or any other make if you want less diameter but more thrust at lower tip speeds ...usually.

For a large glider like this I would no use less than a 12" on a 3.5 :1 box more usual would be 4:1 or deeper and a larger prp ....as long as the draw on the brushed motor is kept low it will be ok for a fair while ..cook them and you can forget it. A decent Geared brushed set up can be pretty efficient.

[Mark Harris]

I wouldnt even bother with a brushed.. as i said, just drop a brushless outrunner in it. Low RPM's, high torque, move those big props no problem.

[Airboatflyingshp]

Watever comes to hand -this should fly it ........... you've got to remember for each buck you guys spend on brushless we typically have to pay a pound or more :eek: ............. prop size is what your after and a decent rate of climb with payload............ have fun :D .

[Mark Harris]

Can't wait to get onto this, i've been translating the french in the autocad to english so its a little more understandable hehe.