siclick33

I'm looking at options to convert a glider for turbine use.

Having never done this before, is there a guide for size/weight verses power required? I have a model in mind but think it will be too heavy for my Kolibri.

With regard to Kolibri suitable gliders, I know about the Opus but that looks a little bit mental for me. I want something smooth and aerobatic but not necessarily ballistic? Does anyone have any suggestions? There looks to be a couple of cheapish models around (Jamara?) but I'm guessing I'll need to look at something full composite to ensure the wings are strong enough for turbine use.

Any advice/recommendations greatly appreciated.

Ali

My Feedback: (5)

Hi Darren,
It really depends what you want to do with it.
If it is just a power assist to get you aloft then your power to weight ratio can be tiny. Even for my aerobatic gliders I tend to aim for an idea of 0.5 :1 PTW. Anything over that is a bonus.
I have seen many turbine glider conversions work really well. I have also seen a few not so well. The ones that are were so good were a result of someone trying to fly a glider that is not up to the job either too fast, or too strenuously.
Consider if you want to be doing aeros with it, and if so is the model designed for it? We must have all seen that 9m span turbine glider video from years back where the guy just simply flies the wings off the model right??? I have seen a few other cases like this, and its just not pretty!
Also remember the extra speed that is capable with this set up. I remember watching a glider that was obviously too small for the amount of power that was being put through it. Coupled with being under engineered, and over flown ( Too hard, too fast) the end result was inevitable.
Regards Al

schroedm

My Feedback: (1)

What's your budget? I've toyed with this idea for a long time now!

If you don't want Opus like performance then the power to weight only needs to be marginal - a 5m fully composite glider will be happy on a p80

Henke Torphammar

The Opus might be fast, but no need for full power going stright down if you don't feel comfortable with it. F5B gliders do fly very well and very clean, start and lands very nice... but the fuselage are very tight and will just shoe horn in the parts needed.

On this kind of small model the distance between exhaust and vertical stab is short, might be a problem on a conventional stab/fin setup. (anyone messured the temp 0.5-0.7m behind the turbine?!)

One option might be the 2.4m Salto from Baudis (the guys making the Banana slope racer) http://www.icare-rc.com/salto_h101_2_5m.htm. small enough for good performance, yet capable of taking fuel for more then 2min of full power :-)

siclick33

My budget is limited by common sense Ideally I'd like to use the Kolibri so that limits the size somewhat.

One model was looking at was the X-models Stingray but I'm not sure if it would be suitable. It might need the 'oomph' of a P-20 but then I'd be worried about getting it too fast[X(]

http://www.xmodelshop.com/stingray-w...lue-p-269.html

Henke Torphammar

xmodels have some nice ones too but most have too tiny fuselage (such as the blade) or the X-tail.

Jgwright

Darren

I have some video of a 2.6m Salto powered by the first prototype Sprite engine

http://www.youtube.com/watch?v=dD4VyFkS3aI

It was very low power then at under 2Kg so pretty comparable with the Kolibri. It is heavier and its consumption was more then than a Kolibri. We used a 600cc tank and the takeoffs were either from the ground using the wheel or hand launched.

It was a cheap Flyfly model 2.6m wingspan. It needed the wheel beefed up considerably to stand a grass landing. It flew well enough, but died when it went into an irrecoverable spin when descending after the engine had stopped and Dave was making rather too steep descending turns. Despite being flown aggressivly the wings did not fold up and the airframe was strong enough, though I remember Ali muttering that it would not last long!

http://www.sloughrc.com/default.asp?...c:010,b:FlyFly

The best models I have found though are http://www.blue-airlines.com

They do a 2.54m fully composite Swift that might be good. There is some video on the site as well and they look strong models. Have a look at the Swift S1 video towards the end.

http://www.blue-airlines.com/filme-videos.htm

John

Ali

My Feedback: (5)

I looked at that model ( For P-20 power) as well. I settled on a Swift as I hate the fat rear fuselage on the Stingray. I think a Lambert would be working hard to fly that around how you would expect it. I doubt you would ever overspeed that one though.
Easiest option Darren is to get another P-20.. Far more scope on airframes then. I have just had another batch of five arrive, and can offer you a trade in on you lambert if you wanted? ( I have a need to put a lambert on a nice display stand, along with a new JPX that I have here.... Damn I am slowly turning into my dad )
Regards Al

siclick33

Ali, PM sent.

Thanks everyone for all the info; that's all good stuff.

Having had a look at some of the other forums there appears to be a lighter version of the Stingray coming out soon (5kg RTF for pure glider setup) so that might be even better than the 'standard' version.

Is there any advantage in any particular position of the turbine or just plonk it on top where there's room? What's the best way to mount it and is there a good starting point for thrust angle?

siclick33

I've been searching high and low and am currently thinking of going for the Roedel 2.8m Fox.

http://www.roedelmodell.de/allgemeines-6.html

The difficulty I have had is finding something that is light enough to have reasonable performance under power but strong enough not to disintegrate, and big enough to still be a powered glider rather than a sport jet with big wings. From the blurb on their website about the manufacturing process, it looks to be reinforced in the right areas and the (composite reinforced) foam wings seem a work of art from the photos. Ideally I'd have liked composite wings and a little bit bigger but compromises had to be made somewhere My second option was a Graupner 3.5m Fox but it's not readily available and is probably just slighty too heavy.

Ali

My Feedback: (5)

Sounds too small and too light to me..

siclick33

You might be right but I'm going round in circles

Others I have looked at are:

Wildflug 3m - Very little info.
http://www.wildflug.de/equipment/equ...0-4_66-ss.html

Modellstudio - Very little info on the net but look good.
http://www.modellstudio.cz/index.php..._detail&id=507

Airworld 3m - I've heard varying opinions on their gliders and they haven't replied to my email so not jumping to give them my money!

Graupner - My no 1 choice but quoted weight of 6.3Kg without turbine and fuel is probably a bit too much.
http://www.graupner.de/en/products/4...9/product.aspx


I've also looked at the Baudis 4m Salto but I'm not sure if I want to spend that much.
http://www.baudismodel.com/saltoh1014m.php

Ali

My Feedback: (5)

First one looks good. I am just trying to work out what all the prices are for?
Not so keen on the second
I have all but given up trying to deal with Airworld myself, and I thought I was their No1 fan and could tolerate the junk service and lack of response to emails... But of late [:@]
Wow the Graupner one is heavy... Are you sure thats not a typo?
Last one is sweet... Do it! [>:]

jseppanen

I'm all for Paritech - great to deal with andlots of options. Yes, a bit pricy but you really get what you pay for...

Below some pics of my Paritech Elan Acro 6.52m. Maiden on saturday and five more flights the following days. Great flying bird.Absolutely my favorite plane now

jseppanen

Multi-file upload is not working as supposed ...one by one it is then...

siclick33

Very nice.

Do you know the weight? What turbine are you using?

jseppanen

Thanks! Around 23kg. IQ-Hammer 90+. Acceleration (of the plane) is not super fast but once it has gathered some speed verticals are great and speed - well let's say sufficient

snobird

My Feedback: (36)

Ali, any thougths on the new Skymaster turbine powered sailplane

jseppanen

Few more IMHO decent pics from last weekend...

jescardin

My Feedback: (1)

For a Kolibri I would also consider those gliders from Fly Fly Hobby:

1.- For gentle flying and high performance the DG-808S (4.000mm wingspan): http://flyflyhobby.com/products_deta...109164284.html

2.- With an aerobatic pedigree but not overpowered, the Fox (3.000mm wingspan): http://flyflyhobby.com/products_deta...109164284.html

3.- For a really hot aerobatic glider, the Salto (2.680mm wingspan): http://flyflyhobby.com/products_deta...109164284.html

They all have fiberglass fuselages and fully sheeted wood wings, are quite cheap due to Chinese manufacture and easily found in UK as they have been distributed by Ripmax. Quality is quite aceptable although some models may need some reinforcements for turbine power.

I sincerely believe they deserve you have a look at them.

Best Regards,

Jesus Cardin

schroedm

My Feedback: (1)

Janne,

That is a beautiful model! I am currently looking for an airframe that will come in just under 20kg with a P80SE. Got a few in mind but some of the guys want 6months to deliver a kit [&o]

I can see myself ending up a Paritech - how long did you have to wait for yours??

Rgds,
Mark

Redline7000

My Feedback: (2)

If you wait a few months, Skymaster Jets will release this DG-600. Knowing Skymaster, they'll have made an easy job of all that's involved in converting a glider to turbine use, such as turbine incidence angle, equipment placement, etc.

http://www.skymasterjet.com/GliderT.wmv

jseppanen

Hi Mark!

Ordered in Jetpower and received in december - about three months. And it was with all pre-build options.

Xantos

Hello Janne,
I have the 5m DG 303 from Paritech and from your comments I understand that you are not very happy with the performance of the 6.5m with Hammer 90 and 23kg AUW .
Paritech recommends a Wren 44 Gold 10lbs thrust for the 5m and AUW is 12kgs .
Should I install a Wren Supersport instead (18lbs).
Only problem is that it will increase the overall weight by maybe 500gm and will call for an additional fuel tank atleast 500ml
Will it still be structurally sound ? I know the wing has a Carbon D Tube structure.

jseppanen

Hi Xantos!

Actually I'm very pleased with the performance - sorry if I wasn't clear. These low drag gliders go like missiles once you get the speed up. It's just the start you could use some more power - especially if you are flying from a short field. I try to get a video next time

5m Paritech DG-303 and Wren 44 Gold should be a perfect match. With a Supersport it would of course be ballistic...but I would put the 44 in it